**Meet the editor**

Letícia B. A. Rangel, Pharm.D., Ph.D., is an Associate Professor of the Department of Pharmaceutical Sciences and a member of the Biotechnology Program at the Federal University of Espirito Santo (UFES). As the head of the Laboratory of Cellular and Molecular Biology of Human Cancer, coordinates projects on ovarian cancer, breast, lung and kidney, with emphasis on the cellular

and molecular mechanisms of these diseases, the development of biotechnology products and processes, and the discovery of new anticancer molecules. Her scientific network includes the Department of Chemistry (UFES), the Institute of Biophysics Carlos Chagas Filho (Federal University of Rio de Janeiro), the Division of Clinical Research of the Brazilian National Cancer Institute, The Department. of Molecular Medicine, University of Texas at San Antonio (USA), and the Department of Pathology at the Johns Hopkins University (USA), as well as the private sector. Aside from papers published on international journals, and ongoing patents negotiations, she has been awarded by the Brazilian government in recognition to her contribution in cancer research.

Contents

**Preface IX**

**Section 1 Cancer Treatment: Conventional and Innovative Pharmacological Approaches 1**

Leticia BA Rangel and Alice L Herlinger

Chapter 3 **Anticancer Properties of Cardiac Glycosides 65**

Chapter 4 **Liposomes as Carriers of Anticancer Drugs 85**

Leite and Mônica Cristina Oliveira

**Section 2 Combinatorial Strategies to Fight Cancer: Surgery,**

**Radiotherpay, Backytherapy, Chemotherapy, and**

Chapter 5 **The Role of Surgery in the Treatment of Hepatocellular**

Georgios Tsoulfas and Polyxeni Agorastou

Varisa Pongrakhananon

**Hyperthermia 125**

**Carcinoma 127**

Isabella dos Santos Guimarães\*, Renata Dalmaschio Daltoé\*, Alice Laschuk Herlinger, Klesia Pirola Madeira, Taciane Ladislau, Iuri Cordeiro Valadão, Paulo Cilas Morais Lyra Junior, Sarah Fernandes Teixeira, Gustavo Modesto Amorim, Diandra Zipinotti dos Santos, Karina Rangel Demuth and Leticia Batista Azevedo Rangel

Taciane Ladislau, Klesia P Madeira, Renata D Daltoé, Isabella S Guimarães, Sarah F Teixeira, Paulo CM Lyra-Júnior, Iuri C Valadão,

Sávia Caldeira de Araújo Lopes, Cristiane dos Santos Giuberti, Talita Guieiro Ribeiro Rocha, Diêgo dos Santos Ferreira, Elaine Amaral

Chapter 1 **Conventional Cancer Treatment 3**

Chapter 2 **Target Cancer Therapy 37**

### Contents

### **Preface XIII**

### **Section 1 Cancer Treatment: Conventional and Innovative Pharmacological Approaches 1**

### Chapter 1 **Conventional Cancer Treatment 3**

Isabella dos Santos Guimarães\*, Renata Dalmaschio Daltoé\*, Alice Laschuk Herlinger, Klesia Pirola Madeira, Taciane Ladislau, Iuri Cordeiro Valadão, Paulo Cilas Morais Lyra Junior, Sarah Fernandes Teixeira, Gustavo Modesto Amorim, Diandra Zipinotti dos Santos, Karina Rangel Demuth and Leticia Batista Azevedo Rangel


Chapter 6 **Laparoscopic Surgery in Genitourinary Cancer Treatment 147** March Villalba José Antonio

Chapter 15 **Immunotherapy of Urinary Bladder Carcinoma: BCG**

Yi Luo, Eric J. Askeland, Mark R. Newton, Jonathan R. Henning and

Contents **VII**

Chapter 16 **Anti-Angiogenic Active Immunotherapy for Cancers: Dawn of a**

Khanh vinh quoc Luong and Lan Thi Hoang Nguyen

Chapter 19 **The Treatment of Cancer: A Comprehensive Therapeutic Model Entailing a Complex of Interaction Modalities 455**

Chapter 20 **Supportive and Palliative Care in Solid Cancer Patients 487**

Mohamed Azmi Hassali and Saad Bin Othman

Chapter 21 **Impact of Cancer Treatment on Reproductive Health and Options for Fertility Preservation 519**

**Section 6 Perspectives in Cancer Biology and Modeling 539**

Bassam Abdul Rasool Hassan, Zuraidah Binti Mohd Yusoff,

**and Beyond 319**

**New Era? 363**

**and Beyond 389**

Michael A. O'Donnell

Jianping Pan and Lihuang Zhang

Chapter 17 **Nutrigenomics and Cancer Prevention 391** Júlio César Nepomuceno

Chapter 18 **The Impact of Vitamin D in Cancer 417**

R. Saggini and M. Calvani

**Section 5 Supportive Care for Cancer Patients 485**

Kenny A. Rodriguez-Wallberg

Chapter 22 **Sialyl Salivary–Type Amylase Associated with**

Chapter 23 **Role of CREB Protein Family Members in Human Haematological Malignancies 555** Francesca D'Auria and Roberta Di Pietro

**Ovarian Cancer 541** Takanori Moriyama

**Section 4 Multidisciplinarity in Cancer Therapy: Nutrition**


Chapter 15 **Immunotherapy of Urinary Bladder Carcinoma: BCG and Beyond 319**

Yi Luo, Eric J. Askeland, Mark R. Newton, Jonathan R. Henning and Michael A. O'Donnell

Chapter 16 **Anti-Angiogenic Active Immunotherapy for Cancers: Dawn of a New Era? 363**

Jianping Pan and Lihuang Zhang

Chapter 6 **Laparoscopic Surgery in Genitourinary Cancer Treatment 147**

Chapter 7 **Current Strategies in the Management of Adenocarcinoma of**

Chapter 9 **Definitive Chemo-Radiotherapy for Resectable Esophageal Cancer — Unresolved Problems Remain 201**

Chapter 10 **A Review of Radiation Therapy's Role in Early-Stage Breast**

Chapter 11 **Radiosurgery and Hypofractionated Stereotactic Irradiation**

Chapter 13 **Glioblastomas, Astrocytomas: Survival Amelioration Adding**

Chapter 12 **Hyperthermia: Cancer Treatment and Beyond 257**

**Treatment of a Recurrent Case 285**

Chapter 14 **Targeted Cancer Therapy by Dendritic Cell Vaccine 299**

Alberto Gramaglia

Abe

**Section 3 The Immunotherapy of Cancer 297**

**Cancer and an Introduction to Electronic Brachytherapy 223** Brent Herron, Alex Herron, Kathryn Howell, Daniel Chin and Luann

**with Photons or Protons for Tumours of the Skull Base 239** Dante Amelio, Marco Cianchetti, Barbara Rombi, Sabina Vennarini, Francesco Dionisi, Maurizio Amichetti and Giuseppe Minniti

Ahmed Bettaieb, Paulina K. Wrzal and Diana A. Averill-Bates

Gianfranco Baronzio, Gurdev Parmar, Michela De Santis and

**Hyperthermia to Conformal Radiotherapy and Temozolomide — Use of Pegylated Doxorubicin and Hyperthermia in the**

Hiroyuki Abe, Touko Shimamoto, Shinichiro Akiyama and Minako

March Villalba José Antonio

Sergio Huerta and Sean P. Dineen

Chapter 8 **Mesothelioma: An Evidence-Based Review 177** Julie Goudreault and Anne Dagnault

**the Rectum 163**

**VI** Contents

Shouji Shimoyama

Roads


Chapter 24 **Life-Cycling of Cancer: New Concept 583** Marina Shaduri and Marc Bouchoucha

Preface

Notwithstanding the advances in the cancer research field, the related epidemiology data remain dramatic and clearly point to an urge to optimize and innovate the therapeutic ap‐ proaches to fight cancer. Indeed, the elucidation of important aspects of cancer biology and human tumorigenesis has progressively enabled oncologists to provide more accurate can‐ cer diagnosis; thus, guiding more efficiently the treatment of multiple cancer types and sub‐ types. Nonetheless, cancer treatment still challenges researchers and clinicians, as proven by the still impressive and increasing number of worldwide cancer-related deaths, caused ei‐ ther by the disease late diagnosis, surgical limitations or radio/chemoresistance. Adding complexity to the inter-individual variables, cancer comprises multiple diseases harboring diverse genetic and epigenetic signatures, which types and subtypes respond differentially

*Cancer Treatment: Conventional and Innovative Approaches* is an attempt to integrate into a book volume the various aspects of cancer treatment, compiling comprehensive reviews written by an international team of experts in the field. The volume is presented in six sec‐ tions: i) Section 1: Cancer treatment: Conventional and innovative pharmacological ap‐ proaches; ii) Section 2: Combinatorial strategies to fight cancer: Surgery, radiotherapy, backytherapy, chemotherapy, and hyperthermia; iii) Section 3: The immunotherapy of can‐ cer; iv) Section 4: Multidisciplinarity in cancer therapy: nutrition and beyond; v) Section 5: Supportive care for cancer patients; vi) Section 6: Perspectives in cancer biology and model‐ ing. Ultimately, we hope this book can enlighten important issues involved in the manage‐ ment of cancer, summarizing the state-of-the-art knowledge regarding the disease control and treatment; thus, providing means to improve the overall care of patients that daily bat‐

**Prof. Letícia Rangel**

Federal University of Espírito Santo, Brazil

to treatment, and are associated to distinct clinical outcomes.

tle against this potentially lethal condition.

### Preface

Chapter 24 **Life-Cycling of Cancer: New Concept 583**

**VIII** Contents

Marina Shaduri and Marc Bouchoucha

Notwithstanding the advances in the cancer research field, the related epidemiology data remain dramatic and clearly point to an urge to optimize and innovate the therapeutic ap‐ proaches to fight cancer. Indeed, the elucidation of important aspects of cancer biology and human tumorigenesis has progressively enabled oncologists to provide more accurate can‐ cer diagnosis; thus, guiding more efficiently the treatment of multiple cancer types and sub‐ types. Nonetheless, cancer treatment still challenges researchers and clinicians, as proven by the still impressive and increasing number of worldwide cancer-related deaths, caused ei‐ ther by the disease late diagnosis, surgical limitations or radio/chemoresistance. Adding complexity to the inter-individual variables, cancer comprises multiple diseases harboring diverse genetic and epigenetic signatures, which types and subtypes respond differentially to treatment, and are associated to distinct clinical outcomes.

*Cancer Treatment: Conventional and Innovative Approaches* is an attempt to integrate into a book volume the various aspects of cancer treatment, compiling comprehensive reviews written by an international team of experts in the field. The volume is presented in six sec‐ tions: i) Section 1: Cancer treatment: Conventional and innovative pharmacological ap‐ proaches; ii) Section 2: Combinatorial strategies to fight cancer: Surgery, radiotherapy, backytherapy, chemotherapy, and hyperthermia; iii) Section 3: The immunotherapy of can‐ cer; iv) Section 4: Multidisciplinarity in cancer therapy: nutrition and beyond; v) Section 5: Supportive care for cancer patients; vi) Section 6: Perspectives in cancer biology and model‐ ing. Ultimately, we hope this book can enlighten important issues involved in the manage‐ ment of cancer, summarizing the state-of-the-art knowledge regarding the disease control and treatment; thus, providing means to improve the overall care of patients that daily bat‐ tle against this potentially lethal condition.

> **Prof. Letícia Rangel** Federal University of Espírito Santo, Brazil

**Section 1**

**Cancer Treatment: Conventional and Innovative**

**Pharmacological Approaches**

**Cancer Treatment: Conventional and Innovative Pharmacological Approaches**

**Chapter 1**

**Conventional Cancer Treatment**

Alice Laschuk Herlinger, Klesia Pirola Madeira,

Additional information is available at the end of the chapter

The era of cancer chemotherapy began in the 1940s with the first use of nitrogen mustards and antifolate drugs. The practice of cancer medicine has changed dramatically allowing treat‐ ments for many previously fatal cancers. Furthermore, the adjuvant chemotherapy and hormonal therapy can extend life and prevent disease recurrence following surgical resection

Concurrently with the new discoveries of chemotherapeutic agents, the remarkable scientific and technological development allowed understanding of cell biology of human cancer cells and thereby the emergence of targeted therapy. Although the targeted therapy drugs have had outstanding successes in selected types of cancer, new therapies are not likely to replace cytotoxic agents in the foreseeable future. Rather, clinical trials have demonstrated potent

and reproduction in any medium, provided the original work is properly cited.

© 2013 Guimarães\* et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

synergy between targeted molecules and traditional cytotoxic agents.

Taciane Ladislau, Iuri Cordeiro Valadão,

Isabella dos Santos Guimarães\*, Renata Dalmaschio Daltoé\*,

Paulo Cilas Morais Lyra Junior,

Sarah Fernandes Teixeira, Gustavo Modesto Amorim, Diandra Zipinotti dos Santos, Karina Rangel Demuth and Leticia Batista Azevedo Rangel

http://dx.doi.org/10.5772/55282

of diferent types of malignancies.

**1. Introduction**

**Chapter 1**

### **Conventional Cancer Treatment**

Isabella dos Santos Guimarães\*, Renata Dalmaschio Daltoé\*, Alice Laschuk Herlinger, Klesia Pirola Madeira, Taciane Ladislau, Iuri Cordeiro Valadão, Paulo Cilas Morais Lyra Junior, Sarah Fernandes Teixeira, Gustavo Modesto Amorim, Diandra Zipinotti dos Santos, Karina Rangel Demuth and Leticia Batista Azevedo Rangel

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/55282

### **1. Introduction**

The era of cancer chemotherapy began in the 1940s with the first use of nitrogen mustards and antifolate drugs. The practice of cancer medicine has changed dramatically allowing treat‐ ments for many previously fatal cancers. Furthermore, the adjuvant chemotherapy and hormonal therapy can extend life and prevent disease recurrence following surgical resection of diferent types of malignancies.

Concurrently with the new discoveries of chemotherapeutic agents, the remarkable scientific and technological development allowed understanding of cell biology of human cancer cells and thereby the emergence of targeted therapy. Although the targeted therapy drugs have had outstanding successes in selected types of cancer, new therapies are not likely to replace cytotoxic agents in the foreseeable future. Rather, clinical trials have demonstrated potent synergy between targeted molecules and traditional cytotoxic agents.

© 2013 Guimarães\* et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

The compounds used in cancer therapy are quite varied in structure and mechanism of action, including: alkylating agents, antimetabolite analogs, natural products, hormones and hor‐ mone antagonists and a variety of agents directed at specific molecular targets.

the oxazaphosphorine ring on cyclophosphamide. Several metabolites are generated but 4 hydroxycyclophosphamide is considered the most significant as it distributes throughout the body, including reaching the tumor where it is preferentially converted into the active nitrogen

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 5

Afterwards, the active nitrogen mustard will form adducts in the DNA in a sequential alkylation process in which each drug molecule will react with two different nucleotides: firstly it forms a monofunctional adduct followed by a second adduct on the opposite strand of the DNA, forming an interstrand cross-link. This cross-link will prevent strands from separating

Iphosphamide is chemically related to cyclophosphamide by transposition of a chloroethyl group from the exocyclic to endocyclic nitrogen. Clinical investigations have highlighted the lower toxicity of iphosphamide in comparison to that observed for cyclophosphamide [13]. Doxorubicin and iphosphamide remain the backbone of chemotherapy in patients with locally advanced or metastatic soft tissue sarcoma [14]. In the mid 1980s, iphosphamide was found to

Nitrosoureas were synthesized at the National Cancer Institute (NCI) following rational design based on structure-activity relation [16]. Nitrosoureas can react through alkylation with both nucleic acids and proteins or specifically through carbamylation with the latter. In order to acquire its alkylating and carbamylating properties these compounds undergo a nonenzymatic decomposition to form a 2‑chloroethyl carbonium ion, which is highly electrophile and capable of alkylating guanine, cytidine, and adenine. Some compounds of this drug category are: (i) 2‑chloroethylnitrosoureas (*CENUs*); (ii) 1‑(2‑chloroethyl)‑3‑cyclohexyl)‑1‑nitrosourea (*CCNU*, lomustine); (iii) bis(chloroethyl) nitrosourea (*BCNU*, carmustine); (iv) 1‑(2‑chloroeth‐ yl)‑3‑(4‑methylcyclohexyl)‑1‑nitrosourea (*methyl‑CCNU*, semustine); (v) chlorozotocin. The most used nitrosoureas in chemotherapy are the lipid soluble agents CCNU and BCNU. Actually, hydrophobicity is an important feature of this drug category since it allows them trespassing blood-brain barrier promoting their wide usage for brain tumor's treatment as well

Triazene compounds of clinical interest, dacarbazine and temozolomide, are a group of alkylating agents with similar chemical, physical, antitumor and mutagenic properties. Their mechanism of action is mainly related to methylation of *O*6-guanine, mediated by methyldia‐ zonium ion, a highly reactive derivative of the two compounds. The cytotoxic/mutagenic effects of these drugs are based on the presence of DNA *O*6- methylguanine adducts that generate base/base mismatches with cytosine and with thymine. These adducts lead to cell death, or if the cell survives, provoke somatic point mutations represented by C:G→T:A

mustard as described above [11].

**2.2. Diverse alkylating agents**

as non-Hodgkin's lymphoma.

*2.2.2. Triazenes*

*2.2.1. Nitrosoureas*

during replication, inhibiting DNA synthesis [12].

be effective in patients with refractory germ cell tumors [15].

In this chapter we will discuss the history, applications and toxicity, among other aspects, of these agents that, in spite of systemic toxicity and severe side effects, became a mainstay of cancer treatment. As molecularly targeted agents have been used on a quite widespread way among different cancers, it can already be considered a conventional cancer therapy. Even more, as a full chapter of this book will be dedicated to these agents this subject will not be discussed in the present chapter.

### **2. Alkylating agents**

Alkylating agents are genotoxic drugs which affect the nucleic acids and their function by direct binding to the DNA, interfering with replication and transcription resulting in muta‐ tions. In this way, the goal of using these agents is to induce DNA damage in cancer cells, severe enough to provoke them to enter into apoptosis. Alkylating agents act by replacing a hydrogen atom into another molecule by an alkyl radical through the electrolytic attack by the alkylating agent; however, this compound can also react with molecules containing an atom in a lower valence state that will undergo electrolytic attack instead of hydrogen.

Alkylating agents can be divided in several subgroups which include nitrogen mustards, various alkylating agents and platinum coordination complexes. Each one of these groups will be discussed below.

### **2.1. Nitrogen mustards**

Nitrogen mustards were the first clinically useful anticancer agents [1] and its derivatives, such as cyclophosphamide, are still among the most widely used antitumor drugs [2].

Cyclophosphamide is a derivative of nitrogen mustards with a modified chemical structure that confers it a greater specificity for cancer cells [3]. The rational on developing cyclophos‐ phamide was that cancer cells express higher levels of phosphamidase, which is able to cleave the phosphorus-nitrogen (P-N) bond, releasing the nitrogen mustard within the cancer cell [4]; this premise was later proven inaccurate [5]. The first clinical trials with cyclophosphamide occurred in 1958, when this drug was found to be the most effective anticancer compound against 33 cancer types on a 1,000 compounds screening trial [6]. In 1959, cyclophosphamide was approved by the Food and Drug Administration (FDA) as a cytotoxic anticancer com‐ pound, and up until now, over 50 years of its approval, it is still one of the most successful anticancer drugs [5]. Cyclophosphamide is used for the treatment of lymphoma, leukemias, breast and ovary cancers [7-10].

Cyclophosphamide is administered as a prodrug which is highly stable and requires hepatic mixed function oxidase system to be metabolically activated. Hepatic cytochrome P-450 systems are responsible for generating 4-hydroxycyclophosphamide by the hydroxylation of the oxazaphosphorine ring on cyclophosphamide. Several metabolites are generated but 4 hydroxycyclophosphamide is considered the most significant as it distributes throughout the body, including reaching the tumor where it is preferentially converted into the active nitrogen mustard as described above [11].

Afterwards, the active nitrogen mustard will form adducts in the DNA in a sequential alkylation process in which each drug molecule will react with two different nucleotides: firstly it forms a monofunctional adduct followed by a second adduct on the opposite strand of the DNA, forming an interstrand cross-link. This cross-link will prevent strands from separating during replication, inhibiting DNA synthesis [12].

Iphosphamide is chemically related to cyclophosphamide by transposition of a chloroethyl group from the exocyclic to endocyclic nitrogen. Clinical investigations have highlighted the lower toxicity of iphosphamide in comparison to that observed for cyclophosphamide [13]. Doxorubicin and iphosphamide remain the backbone of chemotherapy in patients with locally advanced or metastatic soft tissue sarcoma [14]. In the mid 1980s, iphosphamide was found to be effective in patients with refractory germ cell tumors [15].

### **2.2. Diverse alkylating agents**

### *2.2.1. Nitrosoureas*

The compounds used in cancer therapy are quite varied in structure and mechanism of action, including: alkylating agents, antimetabolite analogs, natural products, hormones and hor‐

In this chapter we will discuss the history, applications and toxicity, among other aspects, of these agents that, in spite of systemic toxicity and severe side effects, became a mainstay of cancer treatment. As molecularly targeted agents have been used on a quite widespread way among different cancers, it can already be considered a conventional cancer therapy. Even more, as a full chapter of this book will be dedicated to these agents this subject will not be

Alkylating agents are genotoxic drugs which affect the nucleic acids and their function by direct binding to the DNA, interfering with replication and transcription resulting in muta‐ tions. In this way, the goal of using these agents is to induce DNA damage in cancer cells, severe enough to provoke them to enter into apoptosis. Alkylating agents act by replacing a hydrogen atom into another molecule by an alkyl radical through the electrolytic attack by the alkylating agent; however, this compound can also react with molecules containing an atom

Alkylating agents can be divided in several subgroups which include nitrogen mustards, various alkylating agents and platinum coordination complexes. Each one of these groups will

Nitrogen mustards were the first clinically useful anticancer agents [1] and its derivatives, such

Cyclophosphamide is a derivative of nitrogen mustards with a modified chemical structure that confers it a greater specificity for cancer cells [3]. The rational on developing cyclophos‐ phamide was that cancer cells express higher levels of phosphamidase, which is able to cleave the phosphorus-nitrogen (P-N) bond, releasing the nitrogen mustard within the cancer cell [4]; this premise was later proven inaccurate [5]. The first clinical trials with cyclophosphamide occurred in 1958, when this drug was found to be the most effective anticancer compound against 33 cancer types on a 1,000 compounds screening trial [6]. In 1959, cyclophosphamide was approved by the Food and Drug Administration (FDA) as a cytotoxic anticancer com‐ pound, and up until now, over 50 years of its approval, it is still one of the most successful anticancer drugs [5]. Cyclophosphamide is used for the treatment of lymphoma, leukemias,

Cyclophosphamide is administered as a prodrug which is highly stable and requires hepatic mixed function oxidase system to be metabolically activated. Hepatic cytochrome P-450 systems are responsible for generating 4-hydroxycyclophosphamide by the hydroxylation of

in a lower valence state that will undergo electrolytic attack instead of hydrogen.

as cyclophosphamide, are still among the most widely used antitumor drugs [2].

mone antagonists and a variety of agents directed at specific molecular targets.

discussed in the present chapter.

4 Cancer Treatment - Conventional and Innovative Approaches

**2. Alkylating agents**

be discussed below.

**2.1. Nitrogen mustards**

breast and ovary cancers [7-10].

Nitrosoureas were synthesized at the National Cancer Institute (NCI) following rational design based on structure-activity relation [16]. Nitrosoureas can react through alkylation with both nucleic acids and proteins or specifically through carbamylation with the latter. In order to acquire its alkylating and carbamylating properties these compounds undergo a nonenzymatic decomposition to form a 2‑chloroethyl carbonium ion, which is highly electrophile and capable of alkylating guanine, cytidine, and adenine. Some compounds of this drug category are: (i) 2‑chloroethylnitrosoureas (*CENUs*); (ii) 1‑(2‑chloroethyl)‑3‑cyclohexyl)‑1‑nitrosourea (*CCNU*, lomustine); (iii) bis(chloroethyl) nitrosourea (*BCNU*, carmustine); (iv) 1‑(2‑chloroeth‐ yl)‑3‑(4‑methylcyclohexyl)‑1‑nitrosourea (*methyl‑CCNU*, semustine); (v) chlorozotocin. The most used nitrosoureas in chemotherapy are the lipid soluble agents CCNU and BCNU. Actually, hydrophobicity is an important feature of this drug category since it allows them trespassing blood-brain barrier promoting their wide usage for brain tumor's treatment as well as non-Hodgkin's lymphoma.

### *2.2.2. Triazenes*

Triazene compounds of clinical interest, dacarbazine and temozolomide, are a group of alkylating agents with similar chemical, physical, antitumor and mutagenic properties. Their mechanism of action is mainly related to methylation of *O*6-guanine, mediated by methyldia‐ zonium ion, a highly reactive derivative of the two compounds. The cytotoxic/mutagenic effects of these drugs are based on the presence of DNA *O*6- methylguanine adducts that generate base/base mismatches with cytosine and with thymine. These adducts lead to cell death, or if the cell survives, provoke somatic point mutations represented by C:G→T:A transition in DNA helix. Triazene compounds have excellent pharmacokinetic properties and limited toxicity [17].

cervix, and endometrium cancers; all forms of lung carcinoma; anal and rectal carcinomas; and

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 7

Resistance and the spectrum of clinical activity of carboplatin are similar to those of cisplatin. Carboplatin is relatively well tolerated clinically, causing less nausea, neurotoxicity, ototoxic‐ ity, and nephrotoxicity than cisplatin. Instead, the dose-limiting toxicity is myelosuppression,

Oxaliplatin exhibits a variety of antitumor activity such as against colorectal and gastric cancers which differs from other platinum agents [27]. A great number of phase II and III trials in solid tumors administering oxaliplatin in combination with other drugs have suggested increased activity as compared to oxaliplatin alone. Further, in comparison to cisplatin, oxaliplatin has not demonstrated nephrotoxic effects, which is due to the absence of platinum accumulation

Antimetabolites are cytotoxic agents developed for more than 65 years and considered a mainstay in cancer chemotherapy. The antimetabolites can be divided according with their structure and function as folic acid analogs, purine analogs, pyrimidine analogs and cytidine

These agents are structurally similar to natural metabolites, which are essential for normal biochemical reactions in cells. The mechanism of action of antimetabolites include: competition for binding sites of enzymes that participate in essential biosynthetic processes and incorpo‐ ration into nucleic acids, which inhibits their normal function triggering the apoptosis process.

In 1948, aminopterin, an antifolate drug, was the first drug to induce temporary remissions in children with acute lymphoblastic leukemia (ALL) [29]. This success stimulated research into new antimetabolites less toxic than aminopterin. A few years later another antifolate drug, methotrexate (MTX) showed anticancer property. Currently, this drug category plays an important role in cancer treatment acting in several ways. Mostly they compete with folates for uptake into cells and prevent the formation of folates coenzymes primarily by inhibiting

Mammalian cells lack the ability to synthesize their own reduced folate derivatives and therefore must obtain them from exogenous sources (i.e. food and dietary supplements). In normal and cancer cells, folic acid is reduced to dihydrofolate (FH2) and then to active tetrahydrofolate (FH4) by the enzyme DHFR. FH4 is a cofactor that provides methyl groups for the synthesis of precursors of DNA (thymidylate and purines) and RNA (purines). TS catalyses transfer of the carbon from the FH4 to the target molecules by oxidizing the folate ring of the

dihydrofolate reductase (DHFR) or thymidylate synthase (TS).

neoplasms of childhood [27,25].

primarily thrombocytopenia [27].

in plasma [28].

analogs.

**3. Antimetabolites**

**3.1. Folic acids analogs**

FH4, reverting it back into a FH2 [30].

Temozolomide is an oral alkylating agent with established antitumor activity in patients with melanoma and primary brain tumors, due to its excellent bioavailability in the central nervous system [18]. Dacarbazine is employed to treat Hodgkin disease and malignant melanoma [19,20].

#### **2.3. Platinum complexes**

Rosenberg and colleagues reported, in 1965 the discovery that platinum complexes present in nutrient medium in low concentrations can inhibit cell division of *Escherichia coli* and cause the development of long filaments [21]. In the seventies the efficacy in human cancer patients was established [22].

Since then, over 3,000 platinum derivatives have been synthesized and tested against cancer cells [23]. Because of renal, oto and neurotoxicities of cisplatin, there were intensive efforts to devise analogs with fewer of these serious side effects. Moreover, analogs of cisplatin have been developed in an attempt not only to lessen the toxicity of the parent compound, but also to try to overcome the problem of platinum resistance, which may be present either in the outset of the disease, or emerging during its course or yet be acquired as a result of the treatment [24]. This effort led to the development of carboplatin, which produces primarily hematopoietic toxicity and has antitumor effects similar to those of cisplatin. Other platinum compounds have been developed and evaluated, as described later, although they haven't showed any significant advantages over cisplatin and carboplatin [25].

Today, six platinum compounds are used clinically: cisplatin (available since 1978); carboplatin and oxaliplatin (world-wide 2nd generation analogs); nedaplatin (also a 2nd generation analog); and lobaplatin and heptaplatin (3rd generation analogs). Some platinum complexes are still under clinical investigation, including those developed for oral administration.

Cytotoxicity of platinum compounds is believed to result from the formation of platinum-DNA adducts [26]. In fact, these platinum drugs can be considered as prodrugs, yielding after aquation the active diaquo-platinum compound. The main differences between these prodrugs can be related to the different kinetics of activation. Hydrolysis of cisplatin is extremely rapid, whereas it is slower for carboplatin and nedaplatin. The diaquo-platinum species react with the amine groups of proteins, RNA and DNA. The latter reaction yields platinum-DNA adducts, which appears to be associated with antitumor activity. Aquated platinum reacts preferentially with the N-7 position of guanine and adenine and produces cross-links between bases in the same strand (intrastrand) or opposite strands (interstrand). The efficacy of platinum agents against cancer cells may be mediated with the inhibition of DNA synthesis or saturation of the cellular capacity to repair platinum adducts on DNA [22].

Cisplatin is used alone and in combination with a wide range of other drugs. In combination with bleomycin, etoposide, iphosphamide, or vinblastine, cures 90% of patients with testicular cancer. Cisplatin or carboplatin used with paclitaxel induces complete response in the majority of patients with ovary carcinoma. Cisplatin produces responses in bladder, head and neck, cervix, and endometrium cancers; all forms of lung carcinoma; anal and rectal carcinomas; and neoplasms of childhood [27,25].

Resistance and the spectrum of clinical activity of carboplatin are similar to those of cisplatin. Carboplatin is relatively well tolerated clinically, causing less nausea, neurotoxicity, ototoxic‐ ity, and nephrotoxicity than cisplatin. Instead, the dose-limiting toxicity is myelosuppression, primarily thrombocytopenia [27].

Oxaliplatin exhibits a variety of antitumor activity such as against colorectal and gastric cancers which differs from other platinum agents [27]. A great number of phase II and III trials in solid tumors administering oxaliplatin in combination with other drugs have suggested increased activity as compared to oxaliplatin alone. Further, in comparison to cisplatin, oxaliplatin has not demonstrated nephrotoxic effects, which is due to the absence of platinum accumulation in plasma [28].

### **3. Antimetabolites**

transition in DNA helix. Triazene compounds have excellent pharmacokinetic properties and

Temozolomide is an oral alkylating agent with established antitumor activity in patients with melanoma and primary brain tumors, due to its excellent bioavailability in the central nervous system [18]. Dacarbazine is employed to treat Hodgkin disease and malignant melanoma

Rosenberg and colleagues reported, in 1965 the discovery that platinum complexes present in nutrient medium in low concentrations can inhibit cell division of *Escherichia coli* and cause the development of long filaments [21]. In the seventies the efficacy in human cancer patients

Since then, over 3,000 platinum derivatives have been synthesized and tested against cancer cells [23]. Because of renal, oto and neurotoxicities of cisplatin, there were intensive efforts to devise analogs with fewer of these serious side effects. Moreover, analogs of cisplatin have been developed in an attempt not only to lessen the toxicity of the parent compound, but also to try to overcome the problem of platinum resistance, which may be present either in the outset of the disease, or emerging during its course or yet be acquired as a result of the treatment [24]. This effort led to the development of carboplatin, which produces primarily hematopoietic toxicity and has antitumor effects similar to those of cisplatin. Other platinum compounds have been developed and evaluated, as described later, although they haven't

Today, six platinum compounds are used clinically: cisplatin (available since 1978); carboplatin and oxaliplatin (world-wide 2nd generation analogs); nedaplatin (also a 2nd generation analog); and lobaplatin and heptaplatin (3rd generation analogs). Some platinum complexes are still

Cytotoxicity of platinum compounds is believed to result from the formation of platinum-DNA adducts [26]. In fact, these platinum drugs can be considered as prodrugs, yielding after aquation the active diaquo-platinum compound. The main differences between these prodrugs can be related to the different kinetics of activation. Hydrolysis of cisplatin is extremely rapid, whereas it is slower for carboplatin and nedaplatin. The diaquo-platinum species react with the amine groups of proteins, RNA and DNA. The latter reaction yields platinum-DNA adducts, which appears to be associated with antitumor activity. Aquated platinum reacts preferentially with the N-7 position of guanine and adenine and produces cross-links between bases in the same strand (intrastrand) or opposite strands (interstrand). The efficacy of platinum agents against cancer cells may be mediated with the inhibition of DNA synthesis

Cisplatin is used alone and in combination with a wide range of other drugs. In combination with bleomycin, etoposide, iphosphamide, or vinblastine, cures 90% of patients with testicular cancer. Cisplatin or carboplatin used with paclitaxel induces complete response in the majority of patients with ovary carcinoma. Cisplatin produces responses in bladder, head and neck,

showed any significant advantages over cisplatin and carboplatin [25].

under clinical investigation, including those developed for oral administration.

or saturation of the cellular capacity to repair platinum adducts on DNA [22].

limited toxicity [17].

6 Cancer Treatment - Conventional and Innovative Approaches

**2.3. Platinum complexes**

was established [22].

[19,20].

Antimetabolites are cytotoxic agents developed for more than 65 years and considered a mainstay in cancer chemotherapy. The antimetabolites can be divided according with their structure and function as folic acid analogs, purine analogs, pyrimidine analogs and cytidine analogs.

These agents are structurally similar to natural metabolites, which are essential for normal biochemical reactions in cells. The mechanism of action of antimetabolites include: competition for binding sites of enzymes that participate in essential biosynthetic processes and incorpo‐ ration into nucleic acids, which inhibits their normal function triggering the apoptosis process.

### **3.1. Folic acids analogs**

In 1948, aminopterin, an antifolate drug, was the first drug to induce temporary remissions in children with acute lymphoblastic leukemia (ALL) [29]. This success stimulated research into new antimetabolites less toxic than aminopterin. A few years later another antifolate drug, methotrexate (MTX) showed anticancer property. Currently, this drug category plays an important role in cancer treatment acting in several ways. Mostly they compete with folates for uptake into cells and prevent the formation of folates coenzymes primarily by inhibiting dihydrofolate reductase (DHFR) or thymidylate synthase (TS).

Mammalian cells lack the ability to synthesize their own reduced folate derivatives and therefore must obtain them from exogenous sources (i.e. food and dietary supplements). In normal and cancer cells, folic acid is reduced to dihydrofolate (FH2) and then to active tetrahydrofolate (FH4) by the enzyme DHFR. FH4 is a cofactor that provides methyl groups for the synthesis of precursors of DNA (thymidylate and purines) and RNA (purines). TS catalyses transfer of the carbon from the FH4 to the target molecules by oxidizing the folate ring of the FH4, reverting it back into a FH2 [30].

### *3.1.1. Methotrexate*

Although several antifolate drugs have been developed, MTX is the antifolate with the widest spectrum of use. MTX is extensively used in lymphoma, ALL and osteosarcoma. Moreover, MTX is part of chemotherapeutic schemes for choriocarcinoma, breast, bladder and head and neck cancer [27].

primarily the cladribine, pentostatin, and fludarabine. PNAs have an important role as

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 9

The 6-mercaptopurine (6-MP) was one of the first chemotherapeutic agents to be used in acute leukemia, remaining up today as one of the most useful drugs in acute leukemia's treatment [41,42]. In 1953 FDA approved the usage of 6-MP after a short 2 years mean time period of its synthesis. At this time there were only MTX and steroids as established treatment options for

This chemotherapeutic agent is a prodrug, analogue of hypoxanthine, a naturally occurring purine derivative. 6-MP requires intracellular conversion into 6-thioinosine-5'-monophos‐ phate (TIMP) by the hypoxanthine guanine phosphoribosyl transferase (HGPRT). TIMP is a substrate of thiopurine S-methyltransferase (TPMT) producing methylated TIMP which is an effective inhibitor of de novo purine biosynthesis. The TIMP that is not involved in catabolism is further metabolized by inosine monophosphate dehydrogenase (IMPDH) and later metab‐ olized by a series of kinases and reductases to produce deoxy-6-thioguanosine5'triphosphate (thio-dGTP). Incorporation of thio-dGTP has been shown to trigger cell-cycle arrest and

Fludarabine phosphate (FAMP) has activity in various indolent B cell malignancies and it was approved in 1991 for clinical usage in the treatment of chronic lymphocytic leukemia (CLL). FAMP is a prodrug that requires metabolic conversion to exert cytotoxic activity. It is rapidly dephosphorylated to 9-β-D-arabinosyl-2-fluoroadenine (F-ara-A), transported into cells and then phosphorylated by deoxycytidine kinase to the active form 2-fluoro-ara-ATP (F-ara-ATP) [45,46]. The F-ara-ATP is the only metabolite of FAMP that have cytotoxic activity, acting

F-ara-ATP inhibits ribonucleotide reductase (RNR), responsible for the conversion of ribonu‐ cleotides into deoxyribonucleotides which in turn are one of the key components at the construction of DNA strands. Furthermore F-ara-ATP incorporates into DNA, at the 3' terminus, resulting in repression of DNA polymerization as well as inhibition of DNA ligase, an enzyme involved in DNA replication [47] and DNA primase, an accessory protein that synthesizes an RNA primer required for initiation of synthesis by DNA polymerase [48].

The most frequent adverse events associated with FAMP regimens are myelosuppression lymphocytopenia and infection, typically on respiratory tract. Despite the minor occurrence,

Likewise FAMP, cladribine (2-CdA; 2-chloro-2'-deoxyadenosine) is phosphorylated and accumulated as 2-chlorodeoxyadenosine triphosphate (2-CdA-TP) in cells [50]. This metabolite

severe neurotoxicity is one of the complications associated with FAMP [49].

chemotherapeutic agents in hematological malignancies [40].

ALL, the commonest childhood cancer [43].

apoptosis involving the DNA mismatch repair [44].

through different mechanisms that affect DNA synthesis.

*3.2.1. 6-Mercaptopurine*

*3.2.2. Fludarabine*

*3.2.3. Cladribine*

MTX enters the cells via reduced folate carrier (RFC) or via the membrane folate binding protein (FBP) and is polyglutamated by folylpolyglutamate synthetase (FPGS) in MTXpolyglutamate, which is retained in cells for longer periods compared with MTX [31,32]. The main target of MTX and MTX-polyglutamate is the inhibition of DHFR enzyme, leading to partial depletion of the FH4 cofactors required for the synthesis of new thymidylate and purines nucleotides. Consequently, there will be a decrease of DNA and RNA synthesis. In addition, MTX-polyglutamates are also inhibitors of other folate-requiring enzymes such as: TS and two enzymes related with de novo purine synthesis - glycinamide ribonucleotide transformylase (GART) and aminoimidazole carboxamide ribonucleotide transformylase (AICART) [31].

In normal cells a decreased polyglutamation is observed when compared to malignant cells, which partially explains the selectivity of MTX for malignant tissue [33]. Despite this predilection for malignant cells, MTX can kill rapidly dividing normal cells such as those of the intestinal epithelium and bone marrow [34]. Common side effects are cytopenia, serious infections, liver damage, mucocutaneous problems, alopecia and allergic interstitial pneumo‐ nitis [35].

### *3.1.2. Pemetrexed*

Pemetrexed is a multitargeted antifolate chemotherapy agent approved by FDA in 2004 for the treatment of malignant pleural mesothelioma (MPM) and advanced or metastatic nonsmall cell lung cancer (NSCLC). Ongoing clinical trials are evaluating pemetrexed efficacy in other malignancies such as breast, colorectal, bladder, cervical, gastric and pancreatic cancer [36].

Likewise MTX, pemetrexed inhibits DHFR and as a polyglutamate, it inhibits even more potently GART and TS [37]. The inhibition of TS and GART predominates because peme‐ trexed's usage produces little changes in the pool of reduced folates.

Currently, this agent is employed as a monotherapy or in combination with cisplatin. It is generally a well-tolerated drug and the most common adverse reactions with its usage as single-agent are fatigue, nausea, and anorexia. Myelosuppression is the most common and dose-limiting toxicity, predominantly developed as neutropenia [38].

### **3.2. Purine analogs**

Purine nucleoside analogues (PNA) were identified for the first time by Hitchings and Elion in 1942 with antileukemic and immunosuppressant properties [39]. The 6-mercaptopurine (6- MP) is the oldest PNA approved for clinical use, employed in the treatment of acute leukemias. The next generation of PNAs has been available worldwide since the 1990s, comprising primarily the cladribine, pentostatin, and fludarabine. PNAs have an important role as chemotherapeutic agents in hematological malignancies [40].

### *3.2.1. 6-Mercaptopurine*

*3.1.1. Methotrexate*

8 Cancer Treatment - Conventional and Innovative Approaches

neck cancer [27].

nitis [35].

cancer [36].

**3.2. Purine analogs**

*3.1.2. Pemetrexed*

Although several antifolate drugs have been developed, MTX is the antifolate with the widest spectrum of use. MTX is extensively used in lymphoma, ALL and osteosarcoma. Moreover, MTX is part of chemotherapeutic schemes for choriocarcinoma, breast, bladder and head and

MTX enters the cells via reduced folate carrier (RFC) or via the membrane folate binding protein (FBP) and is polyglutamated by folylpolyglutamate synthetase (FPGS) in MTXpolyglutamate, which is retained in cells for longer periods compared with MTX [31,32]. The main target of MTX and MTX-polyglutamate is the inhibition of DHFR enzyme, leading to partial depletion of the FH4 cofactors required for the synthesis of new thymidylate and purines nucleotides. Consequently, there will be a decrease of DNA and RNA synthesis. In addition, MTX-polyglutamates are also inhibitors of other folate-requiring enzymes such as: TS and two enzymes related with de novo purine synthesis - glycinamide ribonucleotide transformylase (GART) and aminoimidazole carboxamide ribonucleotide transformylase (AICART) [31].

In normal cells a decreased polyglutamation is observed when compared to malignant cells, which partially explains the selectivity of MTX for malignant tissue [33]. Despite this predilection for malignant cells, MTX can kill rapidly dividing normal cells such as those of the intestinal epithelium and bone marrow [34]. Common side effects are cytopenia, serious infections, liver damage, mucocutaneous problems, alopecia and allergic interstitial pneumo‐

Pemetrexed is a multitargeted antifolate chemotherapy agent approved by FDA in 2004 for the treatment of malignant pleural mesothelioma (MPM) and advanced or metastatic nonsmall cell lung cancer (NSCLC). Ongoing clinical trials are evaluating pemetrexed efficacy in other malignancies such as breast, colorectal, bladder, cervical, gastric and pancreatic

Likewise MTX, pemetrexed inhibits DHFR and as a polyglutamate, it inhibits even more potently GART and TS [37]. The inhibition of TS and GART predominates because peme‐

Currently, this agent is employed as a monotherapy or in combination with cisplatin. It is generally a well-tolerated drug and the most common adverse reactions with its usage as single-agent are fatigue, nausea, and anorexia. Myelosuppression is the most common and

Purine nucleoside analogues (PNA) were identified for the first time by Hitchings and Elion in 1942 with antileukemic and immunosuppressant properties [39]. The 6-mercaptopurine (6- MP) is the oldest PNA approved for clinical use, employed in the treatment of acute leukemias. The next generation of PNAs has been available worldwide since the 1990s, comprising

trexed's usage produces little changes in the pool of reduced folates.

dose-limiting toxicity, predominantly developed as neutropenia [38].

The 6-mercaptopurine (6-MP) was one of the first chemotherapeutic agents to be used in acute leukemia, remaining up today as one of the most useful drugs in acute leukemia's treatment [41,42]. In 1953 FDA approved the usage of 6-MP after a short 2 years mean time period of its synthesis. At this time there were only MTX and steroids as established treatment options for ALL, the commonest childhood cancer [43].

This chemotherapeutic agent is a prodrug, analogue of hypoxanthine, a naturally occurring purine derivative. 6-MP requires intracellular conversion into 6-thioinosine-5'-monophos‐ phate (TIMP) by the hypoxanthine guanine phosphoribosyl transferase (HGPRT). TIMP is a substrate of thiopurine S-methyltransferase (TPMT) producing methylated TIMP which is an effective inhibitor of de novo purine biosynthesis. The TIMP that is not involved in catabolism is further metabolized by inosine monophosphate dehydrogenase (IMPDH) and later metab‐ olized by a series of kinases and reductases to produce deoxy-6-thioguanosine5'triphosphate (thio-dGTP). Incorporation of thio-dGTP has been shown to trigger cell-cycle arrest and apoptosis involving the DNA mismatch repair [44].

### *3.2.2. Fludarabine*

Fludarabine phosphate (FAMP) has activity in various indolent B cell malignancies and it was approved in 1991 for clinical usage in the treatment of chronic lymphocytic leukemia (CLL). FAMP is a prodrug that requires metabolic conversion to exert cytotoxic activity. It is rapidly dephosphorylated to 9-β-D-arabinosyl-2-fluoroadenine (F-ara-A), transported into cells and then phosphorylated by deoxycytidine kinase to the active form 2-fluoro-ara-ATP (F-ara-ATP) [45,46]. The F-ara-ATP is the only metabolite of FAMP that have cytotoxic activity, acting through different mechanisms that affect DNA synthesis.

F-ara-ATP inhibits ribonucleotide reductase (RNR), responsible for the conversion of ribonu‐ cleotides into deoxyribonucleotides which in turn are one of the key components at the construction of DNA strands. Furthermore F-ara-ATP incorporates into DNA, at the 3' terminus, resulting in repression of DNA polymerization as well as inhibition of DNA ligase, an enzyme involved in DNA replication [47] and DNA primase, an accessory protein that synthesizes an RNA primer required for initiation of synthesis by DNA polymerase [48].

The most frequent adverse events associated with FAMP regimens are myelosuppression lymphocytopenia and infection, typically on respiratory tract. Despite the minor occurrence, severe neurotoxicity is one of the complications associated with FAMP [49].

#### *3.2.3. Cladribine*

Likewise FAMP, cladribine (2-CdA; 2-chloro-2'-deoxyadenosine) is phosphorylated and accumulated as 2-chlorodeoxyadenosine triphosphate (2-CdA-TP) in cells [50]. This metabolite disrupts cell metabolism by incorporating into the DNA then inhibits DNA synthesis and repair, leading to accumulation of DNA strand breaks [50]. In addiction 2-CdA-TP is a potent inhibitor of RNR.

Usual side effects of 5-FU are gastrointestinal, including nausea, vomiting, diarrhea, and stomatitis. Hematologic effects are also common, like myelosuppression and thrombocytope‐ nia. Although considered unusual, cardiotoxicity has been reported as well as adverse

developed with the objective of improving tolerability and intratumor drug concentrations through tumor-specific conversion to the active drug. This selectivity is due the presence at higher levels of thymidine phosphorylase (TP), the final enzyme responsible for conversion to

In 1998, capecitabine was approved by FDA for the treatment of women with taxane- and anthracycline-refractory advanced breast cancer. Afterwards, this antimetabolite received the

The most common toxicities related to treatment with capecitabine are gastrointestinal effects (diarrhea, nausea and vomiting) and hand-foot syndrome [57]. Other adverse effects were also

The deoxycytidine analogue gemcitabine (difluorodeoxycytidine, dFdC) received its first approval by FDA in 1996 for the treatment of patients with pancreatic cancer and NSCLC. Furthermore, gemcitabine was approved for the first-line treatment of patients with metastatic

Gemcitabine is phosphorylated by deoxycytidine kinase (DCK) to its 5'-monophosphate form (dFdCMP) and additionally metabolized by several other enzymes to its 5'-diphosphate (dFdCDP) and 5'-triphosphate derivatives (dFdCTP). Then, this last metabolite dFdCTP is

The major dose-limiting toxicity of gemcitabine is myelosuppression, but other adverse effects are related with the therapy such as flu-like symptoms, nausea, vomiting and rash [59].

Cytarabine (1-β-D-arabinofuranosylcytosine; ara-C) had its first approval by FDA in 1969 as a chemotherapeutic agent to be used with other drugs for the treatment of adult and pediatric acute myelogenous leukemia (AML). According to the NCI, cytarabine is also approved to treat ALL, chronic myelogenous leukemia (CML) and as a single agent to prevent and treat

Since its approval by FDA in 1969, the clinical effectiveness of this drug has increased with knowledge of its pharmacologic and biologic properties. Ara-C is a prodrug and needs to be converted to its active form, ara-C 5'-triphosphate (Ara-CTP), by a series of intracellular

observed such as alopecia, myelosuppression and cardiotoxicity [57,55].

breast cancer and advanced ovarian cancer, in 2004 and 2006, respectively.

incorporated into DNA, inhibiting DNA replication and inducing apoptosis [58].


Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 11

neurological effects [54,55].

the active drug, in cancer cells [56].

approval for metastatic colorectal carcinoma.

*3.3.2. Capecitabine* Capecitabine (N4

*3.3.3. Gemcitabine*

*3.3.4. Cytarabine*

meningeal leukemia.

enzyme-dependent phosphorylation steps [60].

2-CdA was shown to have potent and long-term effects in the treatment of low-grade B-cell neoplasms, approved by FDA for clinical use in hairy cell leukemia (HCL). It shares the same adverse effects of FAMP, being the bone marrow suppression its major toxic effect, associated with severe infections.

### *3.2.4. Pentostatin*

Pentostatin (deoxycoformycin; DCF) is a natural product first isolated from the culture of *Streptomyces antibioticus* [51] in 1974. This antimetabolite was the first effective agent against HCL, but nowadays its usage has largely been superseded by cladribine.

The primary site of action is the inhibition of adenosine deaminase (ADA), an enzyme that participates in purine salvage metabolic pathways. Inhibition of ADA leads to accumulation of adenosine and deoxyadenosine nucleotides in cells, which can block DNA synthesis by inhibiting RNR. Another important action of pentostatin is the inactivation of S-adenosyl homocysteine hydrolase by deoxyadenosine, resulting in accumulation of S-adenosyl homo‐ cysteine, an intermediate in the synthesis of cysteine and adenosine particularly toxic to lymphocytes. Pentostatin also has adverse effects related with the bone marrow suppression.

### **3.3. Pyrimidine analogs**

Pyrimidine analogs sparked the interest of scientists from the observation that rat malignant tissue used pyrimidine uracil more rapidly than normal tissues [52]. In the late 1950s Charles Heidelberger and colleagues synthesized the fluoropyrimidine 5-fluorouracil (5-FU) [53], which demonstrated specific uracil antagonism within antitumor capabilities. Others pyrimi‐ dine analogs were developed later (e.g. capecitabine, cytosine arabinoside and gemcitabine) and this class is currently extensively used in cancer therapy.

### *3.3.1. Fluouracil*

5-FU is the mainstay of treatment for many common malignant diseases, particularly for colorectal cancer. It's also used in breast, pancreatic and head and neck cancers [52]. This antimetabolite exerts its antitumor effects through several mechanisms including inhibition of the enzyme TS, related to thymidine synthesis from uridine, and incorporation of its metabo‐ lites into RNA and DNA. 5-FU enters into cells rapidly and is converted intracellularly by metabolic enzymes into its active metabolite 5-fluoro-2'-deoxyuridine-5'-monophosphate (FdUMP). FdUMP inhibits TS leading to nucleotide pool imbalance, decreasing thymine concentration which leads to uracil incorporation into DNA causing DNA strand breaks [52]. Another 5-FU metabolite, fluorouridine triphosphate (FUTP) is extensively incorporated into RNA, disrupting normal RNA processing and function.

Usual side effects of 5-FU are gastrointestinal, including nausea, vomiting, diarrhea, and stomatitis. Hematologic effects are also common, like myelosuppression and thrombocytope‐ nia. Although considered unusual, cardiotoxicity has been reported as well as adverse neurological effects [54,55].

### *3.3.2. Capecitabine*

disrupts cell metabolism by incorporating into the DNA then inhibits DNA synthesis and repair, leading to accumulation of DNA strand breaks [50]. In addiction 2-CdA-TP is a potent

2-CdA was shown to have potent and long-term effects in the treatment of low-grade B-cell neoplasms, approved by FDA for clinical use in hairy cell leukemia (HCL). It shares the same adverse effects of FAMP, being the bone marrow suppression its major toxic effect, associated

Pentostatin (deoxycoformycin; DCF) is a natural product first isolated from the culture of *Streptomyces antibioticus* [51] in 1974. This antimetabolite was the first effective agent against

The primary site of action is the inhibition of adenosine deaminase (ADA), an enzyme that participates in purine salvage metabolic pathways. Inhibition of ADA leads to accumulation of adenosine and deoxyadenosine nucleotides in cells, which can block DNA synthesis by inhibiting RNR. Another important action of pentostatin is the inactivation of S-adenosyl homocysteine hydrolase by deoxyadenosine, resulting in accumulation of S-adenosyl homo‐ cysteine, an intermediate in the synthesis of cysteine and adenosine particularly toxic to lymphocytes. Pentostatin also has adverse effects related with the bone marrow suppression.

Pyrimidine analogs sparked the interest of scientists from the observation that rat malignant tissue used pyrimidine uracil more rapidly than normal tissues [52]. In the late 1950s Charles Heidelberger and colleagues synthesized the fluoropyrimidine 5-fluorouracil (5-FU) [53], which demonstrated specific uracil antagonism within antitumor capabilities. Others pyrimi‐ dine analogs were developed later (e.g. capecitabine, cytosine arabinoside and gemcitabine)

5-FU is the mainstay of treatment for many common malignant diseases, particularly for colorectal cancer. It's also used in breast, pancreatic and head and neck cancers [52]. This antimetabolite exerts its antitumor effects through several mechanisms including inhibition of the enzyme TS, related to thymidine synthesis from uridine, and incorporation of its metabo‐ lites into RNA and DNA. 5-FU enters into cells rapidly and is converted intracellularly by metabolic enzymes into its active metabolite 5-fluoro-2'-deoxyuridine-5'-monophosphate (FdUMP). FdUMP inhibits TS leading to nucleotide pool imbalance, decreasing thymine concentration which leads to uracil incorporation into DNA causing DNA strand breaks [52]. Another 5-FU metabolite, fluorouridine triphosphate (FUTP) is extensively incorporated into

HCL, but nowadays its usage has largely been superseded by cladribine.

and this class is currently extensively used in cancer therapy.

RNA, disrupting normal RNA processing and function.

inhibitor of RNR.

10 Cancer Treatment - Conventional and Innovative Approaches

with severe infections.

**3.3. Pyrimidine analogs**

*3.3.1. Fluouracil*

*3.2.4. Pentostatin*

Capecitabine (N4 -pentyloxycarbonyl-5'-deoxy-5-fuorocytidine) is an oral prodrug of 5-FU developed with the objective of improving tolerability and intratumor drug concentrations through tumor-specific conversion to the active drug. This selectivity is due the presence at higher levels of thymidine phosphorylase (TP), the final enzyme responsible for conversion to the active drug, in cancer cells [56].

In 1998, capecitabine was approved by FDA for the treatment of women with taxane- and anthracycline-refractory advanced breast cancer. Afterwards, this antimetabolite received the approval for metastatic colorectal carcinoma.

The most common toxicities related to treatment with capecitabine are gastrointestinal effects (diarrhea, nausea and vomiting) and hand-foot syndrome [57]. Other adverse effects were also observed such as alopecia, myelosuppression and cardiotoxicity [57,55].

### *3.3.3. Gemcitabine*

The deoxycytidine analogue gemcitabine (difluorodeoxycytidine, dFdC) received its first approval by FDA in 1996 for the treatment of patients with pancreatic cancer and NSCLC. Furthermore, gemcitabine was approved for the first-line treatment of patients with metastatic breast cancer and advanced ovarian cancer, in 2004 and 2006, respectively.

Gemcitabine is phosphorylated by deoxycytidine kinase (DCK) to its 5'-monophosphate form (dFdCMP) and additionally metabolized by several other enzymes to its 5'-diphosphate (dFdCDP) and 5'-triphosphate derivatives (dFdCTP). Then, this last metabolite dFdCTP is incorporated into DNA, inhibiting DNA replication and inducing apoptosis [58].

The major dose-limiting toxicity of gemcitabine is myelosuppression, but other adverse effects are related with the therapy such as flu-like symptoms, nausea, vomiting and rash [59].

### *3.3.4. Cytarabine*

Cytarabine (1-β-D-arabinofuranosylcytosine; ara-C) had its first approval by FDA in 1969 as a chemotherapeutic agent to be used with other drugs for the treatment of adult and pediatric acute myelogenous leukemia (AML). According to the NCI, cytarabine is also approved to treat ALL, chronic myelogenous leukemia (CML) and as a single agent to prevent and treat meningeal leukemia.

Since its approval by FDA in 1969, the clinical effectiveness of this drug has increased with knowledge of its pharmacologic and biologic properties. Ara-C is a prodrug and needs to be converted to its active form, ara-C 5'-triphosphate (Ara-CTP), by a series of intracellular enzyme-dependent phosphorylation steps [60].

Its mechanism of action is similar to that of the deoxycytidine analogue Gemcitabine: Ara-C is transported into the cell and once it is inside, it is phosphorylated into ara-C monophosphate (ara-CMP) by DCK and eventually to ara-C triphosphate (ara-CTP) which then competes with deoxycytidine triphosphate (dCTP) for incorporation into DNA and subsequently blocking DNA synthesis causing cell death [60].

Furthermore these compounds diverge in their toxicities. While severe neurotoxicity is observed less frequently with vinorelbine and vinblastine, this side effect is frequently noticed with vincristine [72,73]. Myelosuppression, in turn, predominates with vinblastine and

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 13

Vinca alkaloids and the others MTAs can present resistance in cancer cells due to: (i) cellular efflux of the anticancer agents, especially by the overexpression of drug efflux pumps, such as P-glycoprotein and multidrug resistance-associated protein 1 (MRP1) [75]; (ii) mutations in tubulin at the drug binding sites [76,77]; (iii) changes in the tubulin isotype composition of

Taxanes are natural cytotoxic diterpenes classified as microtubule-stabilizing anticancer agents. Paclitaxel and the semisynthetic analog docetaxel are considered to be among the most

Paclitaxel was identified in 1971 as part of a NCI program that screened medicinal plants for potential anticancer activity, whereof the researchers found cytotoxic effects on solid tumors and leukemic cells [80]. Paclitaxel was initially derived from the bark of the Pacific yew (*Taxus brevifolia*) in a process that a centenary tree provides only a gram of the compound. This lead to a semi-synthetic method that use the 10-deacetylbaccatin-III, which is extracted from more

Docetaxel, in turn, is an esterified derivative of 10-deacetylbaccatin-III, produced by Potier and his colleagues in 1986 [82]. The structures of paclitaxel and docetaxel differ on the ester side chain attached at C-13 and in substitutions at the C-10 taxane ring position, which confers

These drugs interact with β-tubulin promoting tubulin polymerization and formation of stable microtubules, even in the absence of GTP- and microtubule-associated proteins, which are usually essential for these processes. This inhibition of microtubule depolymerization results in mitotic arrest leading to apoptosis of the cancer cells [84]. Furthermore, taxanes have been demonstrated to induce many other cellular effects that may or may not relate to their disruptive effects on microtubule dynamics, including the directly phosphorylation, hence

Paclitaxel was approved by the FDA in 1992 for the treatment of refractory breast cancer and refractory ovarian cancer. Currently this agent has a central role in the treatment of breast, ovarian, NSCLC and AIDS-related Kaposi's sarcoma. In turn, docetaxel received the approval in 1995 for the treatment of metastatic breast cancer. Furthermore was approved for use in hormone refractory prostate cancer (HRPC), advanced squamous cell carcinoma of the head

Treatment with these drugs often results in a number of undesirable side effects, as well as resistance in cancer cells, as mentioned previously. In order to overcome those problems, novel taxanes are in development as well as novel formulations. In 2005 Abraxane® (paclitaxel

inactivation, of proteins that blocks apoptosis in cancer cells (such as bcl-2) [85].

vinorelbine [74] and is the main dose-limiting toxicity of those drugs.

important anticancer drugs in cancer chemotherapy.

abundant yew species such as the European yew *Taxus baccata* [81].

docetaxel slightly more water solubility than paclitaxel [83,25]

and neck, breast cancer, gastric adenocarcinoma and NSCLC.

**4.2. Taxanes**

microtubules [78] and; (iv) changes in micro-tubule-regulatory proteins [79].

Treatment with ara-C is associated with several adverse side effects, including myelosuppres‐ sion (mostly leukopenia, thrombocytopenia and severe anemia), infections, mucositis, neurotoxicity, and acute pulmonary syndrome [61,27]

### **4. Microtubule-target agents**

Microtubules are dynamic structures composed of α–β-tubulin heterodimers and microtu‐ bule-associated proteins representing one of the major components of the cytoskeleton. Microtubules are involved in many cellular processes including maintenance of cell structure, protein transportation and mitosis. Because of the central role of microtubules in mitosis, drugs that affect microtubule are useful in cancer chemotherapy. In this context, Microtubule-Targeted Agents (MTAs) constitute a class of anticancer drugs largely used in the clinics to treat solid tumors and hematological malignancies, either alone or as part of different combi‐ nation regimens. MTA are potent mitotic poisons that are broadly classified into microtubulestabilizing (e.g. taxanes and epothilones) and microtubule-destabilizing (e.g. vinca alkaloids) drugs.

### **4.1. Vinca alkaloids**

The first natural anticancer agents approved to clinical use were the vinca alkaloids vincristine and vinblastine, introduced in the late 1960s. Vinca alkaloids were originally isolated from the Madagascar periwinkle *Catharanthus roseus* and over thirty alkaloids have been obtained of which a few are known definitely to be active [62]. Actually, there are three major vinca alkaloids in clinical use: vinblastine, vincristine and vinorelbine.

Vincas are classified as destabilizing agents due to their ability to cause microtubule depoly‐ merization, suppress treadmilling and dynamic instability, blocking mitotic progression, and ultimately result in cell death by apoptosis. Vinca akaloids bind in one of three sites on tubulin, called the "vinca" domain, located near the exchangeable GTP binding site [63-65].

Vinca alkaloids differ in their chemotherapeutic effectiveness being part of therapeutic schemes in different types of malignancies. Vincristine is used in combination chemotherapy for treating pediatric leukemias, Hodgkin and non-Hodgkin lymphoma, as well as solid tumors such as Wilms tumor and neuroblastoma [66-68]. Vincristine can occasionally be used in the treatment of small cell lung cancer (SCLC). Currently, vinblastine is a standard compo‐ nent of regimens for treating lymphomas including Hodgkin's disease. It´s also used for the treatment of bladder cancer, testicular carcinomas, germ cell malignancies and breast cancer [66,69]. Moreover the semisynthetic derivate of vinblastine, vinorelbine, has activity against NSCLC and breast cancer [70,71].

Furthermore these compounds diverge in their toxicities. While severe neurotoxicity is observed less frequently with vinorelbine and vinblastine, this side effect is frequently noticed with vincristine [72,73]. Myelosuppression, in turn, predominates with vinblastine and vinorelbine [74] and is the main dose-limiting toxicity of those drugs.

Vinca alkaloids and the others MTAs can present resistance in cancer cells due to: (i) cellular efflux of the anticancer agents, especially by the overexpression of drug efflux pumps, such as P-glycoprotein and multidrug resistance-associated protein 1 (MRP1) [75]; (ii) mutations in tubulin at the drug binding sites [76,77]; (iii) changes in the tubulin isotype composition of microtubules [78] and; (iv) changes in micro-tubule-regulatory proteins [79].

### **4.2. Taxanes**

Its mechanism of action is similar to that of the deoxycytidine analogue Gemcitabine: Ara-C is transported into the cell and once it is inside, it is phosphorylated into ara-C monophosphate (ara-CMP) by DCK and eventually to ara-C triphosphate (ara-CTP) which then competes with deoxycytidine triphosphate (dCTP) for incorporation into DNA and subsequently blocking

Treatment with ara-C is associated with several adverse side effects, including myelosuppres‐ sion (mostly leukopenia, thrombocytopenia and severe anemia), infections, mucositis,

Microtubules are dynamic structures composed of α–β-tubulin heterodimers and microtu‐ bule-associated proteins representing one of the major components of the cytoskeleton. Microtubules are involved in many cellular processes including maintenance of cell structure, protein transportation and mitosis. Because of the central role of microtubules in mitosis, drugs that affect microtubule are useful in cancer chemotherapy. In this context, Microtubule-Targeted Agents (MTAs) constitute a class of anticancer drugs largely used in the clinics to treat solid tumors and hematological malignancies, either alone or as part of different combi‐ nation regimens. MTA are potent mitotic poisons that are broadly classified into microtubulestabilizing (e.g. taxanes and epothilones) and microtubule-destabilizing (e.g. vinca alkaloids)

The first natural anticancer agents approved to clinical use were the vinca alkaloids vincristine and vinblastine, introduced in the late 1960s. Vinca alkaloids were originally isolated from the Madagascar periwinkle *Catharanthus roseus* and over thirty alkaloids have been obtained of which a few are known definitely to be active [62]. Actually, there are three major vinca

Vincas are classified as destabilizing agents due to their ability to cause microtubule depoly‐ merization, suppress treadmilling and dynamic instability, blocking mitotic progression, and ultimately result in cell death by apoptosis. Vinca akaloids bind in one of three sites on tubulin,

Vinca alkaloids differ in their chemotherapeutic effectiveness being part of therapeutic schemes in different types of malignancies. Vincristine is used in combination chemotherapy for treating pediatric leukemias, Hodgkin and non-Hodgkin lymphoma, as well as solid tumors such as Wilms tumor and neuroblastoma [66-68]. Vincristine can occasionally be used in the treatment of small cell lung cancer (SCLC). Currently, vinblastine is a standard compo‐ nent of regimens for treating lymphomas including Hodgkin's disease. It´s also used for the treatment of bladder cancer, testicular carcinomas, germ cell malignancies and breast cancer [66,69]. Moreover the semisynthetic derivate of vinblastine, vinorelbine, has activity against

called the "vinca" domain, located near the exchangeable GTP binding site [63-65].

alkaloids in clinical use: vinblastine, vincristine and vinorelbine.

DNA synthesis causing cell death [60].

12 Cancer Treatment - Conventional and Innovative Approaches

**4. Microtubule-target agents**

drugs.

**4.1. Vinca alkaloids**

NSCLC and breast cancer [70,71].

neurotoxicity, and acute pulmonary syndrome [61,27]

Taxanes are natural cytotoxic diterpenes classified as microtubule-stabilizing anticancer agents. Paclitaxel and the semisynthetic analog docetaxel are considered to be among the most important anticancer drugs in cancer chemotherapy.

Paclitaxel was identified in 1971 as part of a NCI program that screened medicinal plants for potential anticancer activity, whereof the researchers found cytotoxic effects on solid tumors and leukemic cells [80]. Paclitaxel was initially derived from the bark of the Pacific yew (*Taxus brevifolia*) in a process that a centenary tree provides only a gram of the compound. This lead to a semi-synthetic method that use the 10-deacetylbaccatin-III, which is extracted from more abundant yew species such as the European yew *Taxus baccata* [81].

Docetaxel, in turn, is an esterified derivative of 10-deacetylbaccatin-III, produced by Potier and his colleagues in 1986 [82]. The structures of paclitaxel and docetaxel differ on the ester side chain attached at C-13 and in substitutions at the C-10 taxane ring position, which confers docetaxel slightly more water solubility than paclitaxel [83,25]

These drugs interact with β-tubulin promoting tubulin polymerization and formation of stable microtubules, even in the absence of GTP- and microtubule-associated proteins, which are usually essential for these processes. This inhibition of microtubule depolymerization results in mitotic arrest leading to apoptosis of the cancer cells [84]. Furthermore, taxanes have been demonstrated to induce many other cellular effects that may or may not relate to their disruptive effects on microtubule dynamics, including the directly phosphorylation, hence inactivation, of proteins that blocks apoptosis in cancer cells (such as bcl-2) [85].

Paclitaxel was approved by the FDA in 1992 for the treatment of refractory breast cancer and refractory ovarian cancer. Currently this agent has a central role in the treatment of breast, ovarian, NSCLC and AIDS-related Kaposi's sarcoma. In turn, docetaxel received the approval in 1995 for the treatment of metastatic breast cancer. Furthermore was approved for use in hormone refractory prostate cancer (HRPC), advanced squamous cell carcinoma of the head and neck, breast cancer, gastric adenocarcinoma and NSCLC.

Treatment with these drugs often results in a number of undesirable side effects, as well as resistance in cancer cells, as mentioned previously. In order to overcome those problems, novel taxanes are in development as well as novel formulations. In 2005 Abraxane® (paclitaxel albumin-bound nanoparticles, solvent-free) was approved for advanced breast cancer. Abraxane® prevent the hypersensitivity reactions typically associated with paclitaxel, which are generally related to the solvent suspension of polyoxyethylated castor oil (Cremophor EL) [86-88].

to treat ovarian, lung and cervical cancer. Irinotecan is a prodrug, currently used for metastatic

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 15

Irinotecan and topotecan produces dose-limiting side effects restricting safety administration and then their anti-tumor efficacy. Diarrhea is the principal side effect related to irinotecan. Moreover the use of this drug can cause nausea, vomiting, anorexia, fatigue, abdominal pain, alopecia and neutropenia. The principal toxicity of topotecan when administered at standard doses is neutropenia, while the nonhematological toxicities are usually mild [100,101].

Podophyllotoxin was first isolated in 1880, but its structure was determined later by Hartwell and Schrecker [102]. Despite the antineoplastic activity, podophyllotoxin was not used in clinical practice due to its toxicity. Several less toxic analogs of podophyllotoxin were produced

While etoposide is most widely used to treat lung cancer and testicular cancer, it is also effective for Hodgkin and non-Hodgkin lymphomas, acute nonlymphocytic leukemia, gastric cancer, and soft-tissue sarcomas. Teniposide has significant activity in SCLC and in the treatment of

The cellular target for etoposide and teniposide is topoisomerase II (Top-II) [106,107]. Top-II enzymes regulate essential cellular processes, including DNA replication and chromosome segregation, by altering the topology of chromosomal DNA. These enzymes induce transient double-stranded breaks in the DNA allowing DNA strands to pass through each other and unwind or unknot tangled DNA. Etoposide and teniposide inhibit Top-II to religate cleaved DNA molecules [108]. This phenomenon leads to accumulation of covalent complexes Top-II-DNA resulting in permanent DNA strand breaks, which trigger mutagenic and cell death

In addition to causing cell death, these agents may, under certain circumstances, lead to neoplastic transformation. Epipodophyllotoxin therapy can cause AML characterized by chromosomal translocations, especially in chromosome 11q23 [110,111]. Other common side effects related to antineoplastic drugs might arise, such as bone marrow suppression, nausea,

The anthracyclines, which include doxorubicin, daunorubicin, epirubicin and idarubicin, are a class of antibiotic chemotherapeutic agents routinely used in the treatment of several cancers. While daunorubicin and idarubicin are more effective in acute leukemias, doxorubicin and

and two analogs were approved for clinical use (etoposide and teniposide).

colorectal cancer.

pathways [109].

vomiting and alopecia.

**7.1. Anthracyclines and anthracenediones**

**7. Antibiotics**

**6. Epipodophyllotoxins**

childhood lymphomas and leukemias [103-105].

Taxanes exerts its primary toxic effects on the bone marrow, mainly neutropenia, and may cause neuropathy [89]. Docetaxel causes greater degrees of neutropenia than paclitaxel. Furthermore, docetaxel can cause fluid retention leading to peripheral edema and pulmonary edema, in extreme cases. Despite the high incidence of major hypersensitivity reactions due to the Cremophor EL vehicle, these reactions are no longer a serious problem due to the advent of effective premedication regimens [90] and new formulations [88].

### **4.3. Epothilones**

Epothilones are a new class of natural cytotoxic antineoplastic microtubule-stabilizing agents. Ixabepilone, a semisynthetic analog of the natural product epothilone B, is the only epothilone approved for cancer therapy, indicated for metastatic breast cancer.

The epothilones competitively inhibit the binding of paclitaxel to polymerized tubulin, indicating that the two compounds share a common binding site despite significant structural differences [90,91]. It has been reported that ixabepilone is less susceptible to drug-resistance mechanisms that limit the efficacy of taxanes, like P-glycoprotein mediated efflux and the overexpression of class III β-tubulin, due to its reduction in polymerization rate of microtu‐ bules [91,92].

Likewise taxanes, ixabepilone is also formulated in Cremophor EL yielding hypersensitivity reactions. Other side effects related to its use are neuropathy, neutropenia, severe diarrhea and fatigue [93,94].

### **5. Camptothecin analogs**

Likewise paclitaxel, camptothecin was discovered as part of a NCI program in 1966 by Wall and Wani [95]. Camptothecin is a pentacyclic quinoline alkaloid present in wood, bark, and fruit of the Asian tree *Camptotheca acuminate*, that specifically target the topoisomerase I (Top-I), a nuclear enzyme that plays a critical role in DNA replication and transcription [96].

Top-I promote relaxation of the supercoiled DNA, prior to transcription, through the formation of a single strand break and religation. The camptothecins bind the covalent Top-I-DNA complex, known as the "cleavable complex", stabilizing it and inhibiting reannealing of the parent DNA. Consequently, camptothecins lead to reversible accumulation of doublestranded DNA breaks and tumor cell death [97-99].

Several derivatives of camptothecin have been synthesized, but only irinotecan and topotecan have been approved for clinical use. Irinotecan and topotecan, which are more soluble and less toxic analogs, are currently used in a wide spectrum of cancers. Topotecan is part of regimens to treat ovarian, lung and cervical cancer. Irinotecan is a prodrug, currently used for metastatic colorectal cancer.

Irinotecan and topotecan produces dose-limiting side effects restricting safety administration and then their anti-tumor efficacy. Diarrhea is the principal side effect related to irinotecan. Moreover the use of this drug can cause nausea, vomiting, anorexia, fatigue, abdominal pain, alopecia and neutropenia. The principal toxicity of topotecan when administered at standard doses is neutropenia, while the nonhematological toxicities are usually mild [100,101].

### **6. Epipodophyllotoxins**

albumin-bound nanoparticles, solvent-free) was approved for advanced breast cancer. Abraxane® prevent the hypersensitivity reactions typically associated with paclitaxel, which are generally related to the solvent suspension of polyoxyethylated castor oil (Cremophor EL)

Taxanes exerts its primary toxic effects on the bone marrow, mainly neutropenia, and may cause neuropathy [89]. Docetaxel causes greater degrees of neutropenia than paclitaxel. Furthermore, docetaxel can cause fluid retention leading to peripheral edema and pulmonary edema, in extreme cases. Despite the high incidence of major hypersensitivity reactions due to the Cremophor EL vehicle, these reactions are no longer a serious problem due to the advent

Epothilones are a new class of natural cytotoxic antineoplastic microtubule-stabilizing agents. Ixabepilone, a semisynthetic analog of the natural product epothilone B, is the only epothilone

The epothilones competitively inhibit the binding of paclitaxel to polymerized tubulin, indicating that the two compounds share a common binding site despite significant structural differences [90,91]. It has been reported that ixabepilone is less susceptible to drug-resistance mechanisms that limit the efficacy of taxanes, like P-glycoprotein mediated efflux and the overexpression of class III β-tubulin, due to its reduction in polymerization rate of microtu‐

Likewise taxanes, ixabepilone is also formulated in Cremophor EL yielding hypersensitivity reactions. Other side effects related to its use are neuropathy, neutropenia, severe diarrhea and

Likewise paclitaxel, camptothecin was discovered as part of a NCI program in 1966 by Wall and Wani [95]. Camptothecin is a pentacyclic quinoline alkaloid present in wood, bark, and fruit of the Asian tree *Camptotheca acuminate*, that specifically target the topoisomerase I (Top-I), a nuclear enzyme that plays a critical role in DNA replication and transcription [96].

Top-I promote relaxation of the supercoiled DNA, prior to transcription, through the formation of a single strand break and religation. The camptothecins bind the covalent Top-I-DNA complex, known as the "cleavable complex", stabilizing it and inhibiting reannealing of the parent DNA. Consequently, camptothecins lead to reversible accumulation of double-

Several derivatives of camptothecin have been synthesized, but only irinotecan and topotecan have been approved for clinical use. Irinotecan and topotecan, which are more soluble and less toxic analogs, are currently used in a wide spectrum of cancers. Topotecan is part of regimens

of effective premedication regimens [90] and new formulations [88].

14 Cancer Treatment - Conventional and Innovative Approaches

approved for cancer therapy, indicated for metastatic breast cancer.

[86-88].

**4.3. Epothilones**

bules [91,92].

fatigue [93,94].

**5. Camptothecin analogs**

stranded DNA breaks and tumor cell death [97-99].

Podophyllotoxin was first isolated in 1880, but its structure was determined later by Hartwell and Schrecker [102]. Despite the antineoplastic activity, podophyllotoxin was not used in clinical practice due to its toxicity. Several less toxic analogs of podophyllotoxin were produced and two analogs were approved for clinical use (etoposide and teniposide).

While etoposide is most widely used to treat lung cancer and testicular cancer, it is also effective for Hodgkin and non-Hodgkin lymphomas, acute nonlymphocytic leukemia, gastric cancer, and soft-tissue sarcomas. Teniposide has significant activity in SCLC and in the treatment of childhood lymphomas and leukemias [103-105].

The cellular target for etoposide and teniposide is topoisomerase II (Top-II) [106,107]. Top-II enzymes regulate essential cellular processes, including DNA replication and chromosome segregation, by altering the topology of chromosomal DNA. These enzymes induce transient double-stranded breaks in the DNA allowing DNA strands to pass through each other and unwind or unknot tangled DNA. Etoposide and teniposide inhibit Top-II to religate cleaved DNA molecules [108]. This phenomenon leads to accumulation of covalent complexes Top-II-DNA resulting in permanent DNA strand breaks, which trigger mutagenic and cell death pathways [109].

In addition to causing cell death, these agents may, under certain circumstances, lead to neoplastic transformation. Epipodophyllotoxin therapy can cause AML characterized by chromosomal translocations, especially in chromosome 11q23 [110,111]. Other common side effects related to antineoplastic drugs might arise, such as bone marrow suppression, nausea, vomiting and alopecia.

### **7. Antibiotics**

### **7.1. Anthracyclines and anthracenediones**

The anthracyclines, which include doxorubicin, daunorubicin, epirubicin and idarubicin, are a class of antibiotic chemotherapeutic agents routinely used in the treatment of several cancers. While daunorubicin and idarubicin are more effective in acute leukemias, doxorubicin and epirubicin display broader activity against human solid tumors. Doxorubicin has a central role in the therapy of breast, lung, gastric, ovarian, thyroid, non-Hodgkin's and Hodgkin's lymphoma, sarcoma and pediatric cancers. Epirubicin is an epimer of doxorubicin indicated as component of therapy for breast cancer [112,113].

The mechanism of action of L-ASNase is based on the assumption that tumor cells, especially leukemic cells, require a huge amount of amino acid asparagine (Asn) to maintain their rapid malignant growth. Those cells lack adequate amounts of asparagine synthetase and are dependent on an exogenous source of Asn for survival. L-ASNase catalyzes the hydrolysis of L-ASN to L-aspartic acid and ammonia, significantly depleting the circulating asparagines

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 17

The most common side effect is related to inhibition of protein synthesis and allergic reactions. Hypersensitivity reactions can be solved by use of modified versions of L-ASNase such as polyethylene glycol (PEG)-conjugated asparaginase (pegasparaginase). Pegasparaginase reduce immunogenic reactions and posses a considerably longer half-life, reducing the number of injections for the patient. In recent years, clinical trials have established the importance of

Resistance arises through induction of asparagine synthetase in tumor cells [123] and admin‐ istrations of ASNase may induce the development of antibodies that neutralize the enzyme

The synthesis of Hydroxyurea (HU) occurred for the first time in 1869 by Dresler and Stein [125], meanwhile its biological activities as a myelossupressive drug were only demonstrated 60 years later [126]. Further studies regarding its mechanism of action were able to demonstrate its activity at impairing DNA synthesis through blocking its deoxyribonucleotides subunits formation by acting at the ribonucleotide reductase (RNR) enzyme [127]. The RNR enzyme inhibited by HU is responsible for the conversion of ribonucleotides into deoxyribonucleotides which in turn are one of the key components at the construction of DNA strands. Once HU is mainly effective at the S phase of the cell cycle, when its target, e.g. the catalytic subunit of RNR, is highly activated in cells, it also provides synergistic effect with radiotherapy [128]. Additionally, regardless of the origin of the HU-induced release of nitric oxide [129,130], its

HU is currently used in combination therapies along with other chemotherapeutic agents and radiation regimens to treat resistant chronic myelocytic leukemia (CML), cervical carcinomas, malignant melanomas, head and neck cancers and brain tumors (e.g., glioma, meningioma)

HU is well-known by its dose-limiting myelosuppressive effect which appears within a few days after the beginning of its use and is mostly reversed through the discontinuation of the drug. Skin and nail hyperpigmentation, malleolar ulcerations and solar hypersensitivity are some of the most observed cutaneous side effects in long-term exposed patients [131,132]. Multiple skin tumors as well as its precursor lesions may also develop after sun exposure

contribution to the antineoplastic effect of HU remains relatively unexplored.

pegasparaginase in frontline pediatric and adult ALL therapy [120,122]

from plasma [27,121].

[120, 121,124].

**9. Diverse agents**

**9.1. Hydroxyurea**

[127,128].

[133,134].

These chemotherapeutic agents attack cancer cells by multiple mechanisms (i) intercalation with DNA and disruption of Top-II, directly affecting DNA replication and repair, (ii) generation of quinone-type free radicals and their damage to cellular membranes, DNA and proteins and (iii) triggering of apoptotic cell death through complex signaling pathways [27,113].

Despite the large use, the most serious toxicity associated with anthracyclins is cardiotoxicity which can be cumulative and irreversible [114]. However, liposomal formulation of doxoru‐ bicin was shown to be less cardiotoxic than traditional doxorubicin without compromising efficacy in adults with solid tumors [115].

Another important antibiotic chemotherapeutic agent is the anthracenediones, which also inhibit Top-II. Mitoxantrone is the most active compound in the anthracenediones class and has been approved for use in AML and prostate cancer [116,117]. It is relevant to point that mitoxantrone has limited ability to produce quinone-type free radicals and causes less cardiac toxicity than does doxorubicin.

### **7.2. Bleomycin**

Bleomycins are a group of glycopeptides antibiotics, isolated in the early 1960s from *Strepto‐ myces verticillis* [118]. Its cytotoxic properties result from generation of free radicals leading to single- and double-stranded breaks in DNA.

Bleomycins are attractive components of chemotherapy regimens due to minimal myelotox‐ icity and immunosuppression whilst the pulmonary toxicity related to its use limits the applicability of this drug [119]. Currently bleomycins have antitumor activity against certain types of lymphoma, testicular tumors, head and neck cancers, Kaposi sarcoma, cervical cancer and germ-cell tumors.

### **8. Enzymes**

### **8.1. L-Asparaginase (L-ASNase)**

L-Asparaginases (L-ASNase) are effective antineoplastic agents used in first-line treatment of a variety of lymphoproliferative disorders, especially in ALL. It has been used in combination with other agents, including methotrexate, doxorubicin, vincristine, and prednisone [120]. Currently, there are three preparations of L-ASNase available for clinical use: native enzyme from *Escherichia coli* (Elspar®); a pegylated *E. coli* L-ASNase (Oncospar®), and native erwinia enzyme from *Erwinia chrysanthemi* (Erwinase®).

The mechanism of action of L-ASNase is based on the assumption that tumor cells, especially leukemic cells, require a huge amount of amino acid asparagine (Asn) to maintain their rapid malignant growth. Those cells lack adequate amounts of asparagine synthetase and are dependent on an exogenous source of Asn for survival. L-ASNase catalyzes the hydrolysis of L-ASN to L-aspartic acid and ammonia, significantly depleting the circulating asparagines from plasma [27,121].

The most common side effect is related to inhibition of protein synthesis and allergic reactions. Hypersensitivity reactions can be solved by use of modified versions of L-ASNase such as polyethylene glycol (PEG)-conjugated asparaginase (pegasparaginase). Pegasparaginase reduce immunogenic reactions and posses a considerably longer half-life, reducing the number of injections for the patient. In recent years, clinical trials have established the importance of pegasparaginase in frontline pediatric and adult ALL therapy [120,122]

Resistance arises through induction of asparagine synthetase in tumor cells [123] and admin‐ istrations of ASNase may induce the development of antibodies that neutralize the enzyme [120, 121,124].

### **9. Diverse agents**

### **9.1. Hydroxyurea**

epirubicin display broader activity against human solid tumors. Doxorubicin has a central role in the therapy of breast, lung, gastric, ovarian, thyroid, non-Hodgkin's and Hodgkin's lymphoma, sarcoma and pediatric cancers. Epirubicin is an epimer of doxorubicin indicated

These chemotherapeutic agents attack cancer cells by multiple mechanisms (i) intercalation with DNA and disruption of Top-II, directly affecting DNA replication and repair, (ii) generation of quinone-type free radicals and their damage to cellular membranes, DNA and proteins and (iii) triggering of apoptotic cell death through complex signaling pathways

Despite the large use, the most serious toxicity associated with anthracyclins is cardiotoxicity which can be cumulative and irreversible [114]. However, liposomal formulation of doxoru‐ bicin was shown to be less cardiotoxic than traditional doxorubicin without compromising

Another important antibiotic chemotherapeutic agent is the anthracenediones, which also inhibit Top-II. Mitoxantrone is the most active compound in the anthracenediones class and has been approved for use in AML and prostate cancer [116,117]. It is relevant to point that mitoxantrone has limited ability to produce quinone-type free radicals and causes less cardiac

Bleomycins are a group of glycopeptides antibiotics, isolated in the early 1960s from *Strepto‐ myces verticillis* [118]. Its cytotoxic properties result from generation of free radicals leading to

Bleomycins are attractive components of chemotherapy regimens due to minimal myelotox‐ icity and immunosuppression whilst the pulmonary toxicity related to its use limits the applicability of this drug [119]. Currently bleomycins have antitumor activity against certain types of lymphoma, testicular tumors, head and neck cancers, Kaposi sarcoma, cervical cancer

L-Asparaginases (L-ASNase) are effective antineoplastic agents used in first-line treatment of a variety of lymphoproliferative disorders, especially in ALL. It has been used in combination with other agents, including methotrexate, doxorubicin, vincristine, and prednisone [120]. Currently, there are three preparations of L-ASNase available for clinical use: native enzyme from *Escherichia coli* (Elspar®); a pegylated *E. coli* L-ASNase (Oncospar®), and native erwinia

as component of therapy for breast cancer [112,113].

16 Cancer Treatment - Conventional and Innovative Approaches

efficacy in adults with solid tumors [115].

single- and double-stranded breaks in DNA.

toxicity than does doxorubicin.

**7.2. Bleomycin**

and germ-cell tumors.

**8.1. L-Asparaginase (L-ASNase)**

enzyme from *Erwinia chrysanthemi* (Erwinase®).

**8. Enzymes**

[27,113].

The synthesis of Hydroxyurea (HU) occurred for the first time in 1869 by Dresler and Stein [125], meanwhile its biological activities as a myelossupressive drug were only demonstrated 60 years later [126]. Further studies regarding its mechanism of action were able to demonstrate its activity at impairing DNA synthesis through blocking its deoxyribonucleotides subunits formation by acting at the ribonucleotide reductase (RNR) enzyme [127]. The RNR enzyme inhibited by HU is responsible for the conversion of ribonucleotides into deoxyribonucleotides which in turn are one of the key components at the construction of DNA strands. Once HU is mainly effective at the S phase of the cell cycle, when its target, e.g. the catalytic subunit of RNR, is highly activated in cells, it also provides synergistic effect with radiotherapy [128]. Additionally, regardless of the origin of the HU-induced release of nitric oxide [129,130], its contribution to the antineoplastic effect of HU remains relatively unexplored.

HU is currently used in combination therapies along with other chemotherapeutic agents and radiation regimens to treat resistant chronic myelocytic leukemia (CML), cervical carcinomas, malignant melanomas, head and neck cancers and brain tumors (e.g., glioma, meningioma) [127,128].

HU is well-known by its dose-limiting myelosuppressive effect which appears within a few days after the beginning of its use and is mostly reversed through the discontinuation of the drug. Skin and nail hyperpigmentation, malleolar ulcerations and solar hypersensitivity are some of the most observed cutaneous side effects in long-term exposed patients [131,132]. Multiple skin tumors as well as its precursor lesions may also develop after sun exposure [133,134].

### **9.2. Thalidomide**

In the late 1950s thalidomide was introduced by Chemie Grunenthal company into the market as a sedative drug and within a few years later the disseminated teratogenic consequences of its use during pregnancy practically banned its worldwide commercialization [135]. Further studies demonstrated the antiangiogenic activity of thalidomide *in vivo* through inhibition of bFGF/VEGF as well as its immunomodularory effects by suppression of the pro-inflamatory TNF-alfa synthesis and T-cell co-stimulatory activity [136]. Those properties encouraged further studies regarding its advantages of usage in a series of cancers, such as multiple myeloma (MM), renal cell carcinoma, prostate cancer, among others [135]. Thalidomide has currently been used in combination with dexamethasone in the treatment of MM [137]. Thalidomide has at least a partial benefit in response to cancer-related cachexia, mitigating the total weight and lean body mass reduction [138,139].

this means, targeting the proteasome structure would lead to inhibition of NF-kB activation. Additionally, bortezomib may also promotes cancer cells to sensitization towards cytotoxic

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 19

The commonest toxic effects related to the use of bortezomib are fatigue, gastrointestinal disturbances, thrombocytopenia, paresthesia and peripheral neuropathy. Besides the adverse events aforementioned, intrinsic/acquired resistance and unsatisfactory response toward solid tumors represent some ofthedisadvantages associated with theutilization of bortezomib [145].

Zoledronic acid is a heterocyclic nitrogen-containing bisphosphonate [146]. Bisphosphonates, such as zoledronic acid, are anti-resorptive agents approved for treatment of skeletal compli‐ cation associated with metastatic breast cancer and prostate cancer. These agents act on osteoclasts, key cells in the bone microenvironment, inhibiting bone resorption [147, 148].

Moreover, zoledronic acid is used extensively in diseases with high bone turnover such as MM. Nephrotoxicity can be observed with use of this drug, and is related to dose, infusion time and plasma concentration. Furthemore, zoledronic acid has a long renal half-life, contributing to renal damage. Osteonecrosis of the jaw is also associated with zoledronic acid

Glucocorticoids are primary stress hormones that function to maintain homeostasis regulating many biological processes, including immune function, skeletal growth, reproduction, cognition, behavior, and cell proliferation and survival [151]. Glucocorticoids act through their binding to a specific physiological receptor that translocates to the nucleus and induces antiproliferative and apoptotic responses in sensitive cells [27]. These actions are important in their

Glucocorticoids, dexamethasone and prednisone, are widely used for the treatment of leuke‐ mias and lymphomas because of their effects on cell cycle progression and apoptosis. They are also adopted as a co-medication in the therapy of solid tumors, either because of their effective‐ ness intreatingthemalignancyorfordecreasingedema,pain, electrolyte imbalance,nauseaand

Progesterone is an essential regulator of normal human female reproductive function in the uterus, ovary, mammary gland and brain, and also plays an important role in non-reproduc‐ tive tissues such as the cardiovascular system, bone and the central nervous system. This highlights the widespread role of this hormone in normal physiology. The effects of progester‐

emesis or yet to reduce cytotoxic reactions caused by other treatment regimens [152].

drugs [145].

[149,150].

**10.1. Glucocorticoids**

**10.2. Progestins**

**10. Hormones and related agents**

usage as therapeutic agents in cancer treatment.

**9.5. Zoledronic acid**

The most common adverse effects associated with thalidomide's employment include constipation and sedation. Meanwhile cardiovascular effects like hypotension and bradycar‐ dia, somnolence, thromboembolism and peripheral neuropathy are the most severe toxic events related to this drug and may require the withdrawal of it, which is generally sufficient to achieve clinical improvement [140,141].

### **9.3. Estramustine**

Estramustine is a nitrogen mustard derivative formed by the union of normustine (nitrogen mustard) and estradiol-17beta-phosphate with antineoplastic effects that rely on its properties as an anti-mitotic drug through disruption of the microtubule organization in HRPC cells as well as by pro-apoptotic events [142]. Recently concluded trials also assigned an additional benefit in treating prostate cancer with the addition of other chemotherapeutics, e.g. docetaxel, in comparison to the administration of estramustine alone [143].

The most common side effects observable within the use of estramustine are vomiting and nausea, affecting nearly 50% of the patients. Meanwhile the pro-estrogenic consequences (gynecomastia, impotence) and thromboembolic events are some of the most severe adverse effects. The latter, specifically is also due to the contribution of the disease itself [143].

#### **9.4. Bortezomib**

Bortezomib was the first proteasome inhibitor approved by the FDA in 2003 as an alternative treatment for refractory MM. Its approval was extended in 2008 for the treatment of newly diagnosed MM. Bortezomib's usage as an anticancer agent was also approved by the FDA in 2006 for the treatment of relapsed or refractory mantle cell lymphoma (MCL) [144].

This drug acts through inhibition of the 26S proteasome by blocking its 20S core subunit's chymotrypsin-like activity, which affects several intracellular signaling pathways, as the NFkB anti-apoptotic pathway. The NF-kB molecule is found directly attached to its inhibitor (IkB) which in turn becomes ubiquitinated and degraded at the proteasome in response to specific stressful situations, releasing NF-kB to enter the nucleus and exert its pro-survival effects. By this means, targeting the proteasome structure would lead to inhibition of NF-kB activation. Additionally, bortezomib may also promotes cancer cells to sensitization towards cytotoxic drugs [145].

The commonest toxic effects related to the use of bortezomib are fatigue, gastrointestinal disturbances, thrombocytopenia, paresthesia and peripheral neuropathy. Besides the adverse events aforementioned, intrinsic/acquired resistance and unsatisfactory response toward solid tumors represent some ofthedisadvantages associated with theutilization of bortezomib [145].

### **9.5. Zoledronic acid**

**9.2. Thalidomide**

**9.3. Estramustine**

**9.4. Bortezomib**

total weight and lean body mass reduction [138,139].

in comparison to the administration of estramustine alone [143].

to achieve clinical improvement [140,141].

18 Cancer Treatment - Conventional and Innovative Approaches

In the late 1950s thalidomide was introduced by Chemie Grunenthal company into the market as a sedative drug and within a few years later the disseminated teratogenic consequences of its use during pregnancy practically banned its worldwide commercialization [135]. Further studies demonstrated the antiangiogenic activity of thalidomide *in vivo* through inhibition of bFGF/VEGF as well as its immunomodularory effects by suppression of the pro-inflamatory TNF-alfa synthesis and T-cell co-stimulatory activity [136]. Those properties encouraged further studies regarding its advantages of usage in a series of cancers, such as multiple myeloma (MM), renal cell carcinoma, prostate cancer, among others [135]. Thalidomide has currently been used in combination with dexamethasone in the treatment of MM [137]. Thalidomide has at least a partial benefit in response to cancer-related cachexia, mitigating the

The most common adverse effects associated with thalidomide's employment include constipation and sedation. Meanwhile cardiovascular effects like hypotension and bradycar‐ dia, somnolence, thromboembolism and peripheral neuropathy are the most severe toxic events related to this drug and may require the withdrawal of it, which is generally sufficient

Estramustine is a nitrogen mustard derivative formed by the union of normustine (nitrogen mustard) and estradiol-17beta-phosphate with antineoplastic effects that rely on its properties as an anti-mitotic drug through disruption of the microtubule organization in HRPC cells as well as by pro-apoptotic events [142]. Recently concluded trials also assigned an additional benefit in treating prostate cancer with the addition of other chemotherapeutics, e.g. docetaxel,

The most common side effects observable within the use of estramustine are vomiting and nausea, affecting nearly 50% of the patients. Meanwhile the pro-estrogenic consequences (gynecomastia, impotence) and thromboembolic events are some of the most severe adverse

Bortezomib was the first proteasome inhibitor approved by the FDA in 2003 as an alternative treatment for refractory MM. Its approval was extended in 2008 for the treatment of newly diagnosed MM. Bortezomib's usage as an anticancer agent was also approved by the FDA in

This drug acts through inhibition of the 26S proteasome by blocking its 20S core subunit's chymotrypsin-like activity, which affects several intracellular signaling pathways, as the NFkB anti-apoptotic pathway. The NF-kB molecule is found directly attached to its inhibitor (IkB) which in turn becomes ubiquitinated and degraded at the proteasome in response to specific stressful situations, releasing NF-kB to enter the nucleus and exert its pro-survival effects. By

effects. The latter, specifically is also due to the contribution of the disease itself [143].

2006 for the treatment of relapsed or refractory mantle cell lymphoma (MCL) [144].

Zoledronic acid is a heterocyclic nitrogen-containing bisphosphonate [146]. Bisphosphonates, such as zoledronic acid, are anti-resorptive agents approved for treatment of skeletal compli‐ cation associated with metastatic breast cancer and prostate cancer. These agents act on osteoclasts, key cells in the bone microenvironment, inhibiting bone resorption [147, 148].

Moreover, zoledronic acid is used extensively in diseases with high bone turnover such as MM. Nephrotoxicity can be observed with use of this drug, and is related to dose, infusion time and plasma concentration. Furthemore, zoledronic acid has a long renal half-life, contributing to renal damage. Osteonecrosis of the jaw is also associated with zoledronic acid [149,150].

### **10. Hormones and related agents**

### **10.1. Glucocorticoids**

Glucocorticoids are primary stress hormones that function to maintain homeostasis regulating many biological processes, including immune function, skeletal growth, reproduction, cognition, behavior, and cell proliferation and survival [151]. Glucocorticoids act through their binding to a specific physiological receptor that translocates to the nucleus and induces antiproliferative and apoptotic responses in sensitive cells [27]. These actions are important in their usage as therapeutic agents in cancer treatment.

Glucocorticoids, dexamethasone and prednisone, are widely used for the treatment of leuke‐ mias and lymphomas because of their effects on cell cycle progression and apoptosis. They are also adopted as a co-medication in the therapy of solid tumors, either because of their effective‐ ness intreatingthemalignancyorfordecreasingedema,pain, electrolyte imbalance,nauseaand emesis or yet to reduce cytotoxic reactions caused by other treatment regimens [152].

### **10.2. Progestins**

Progesterone is an essential regulator of normal human female reproductive function in the uterus, ovary, mammary gland and brain, and also plays an important role in non-reproduc‐ tive tissues such as the cardiovascular system, bone and the central nervous system. This highlights the widespread role of this hormone in normal physiology. The effects of progester‐ one are mediated through the nuclear progesterone receptor (PR), which interacts with transcriptionalcoregulators,movesintonuclearaggregatesandregulatesgeneexpression[153].

treatment of metastatic breast cancer in postmenopausal women with ER+ or tumors with

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 21

Due to its agonistic properties, tamoxifen significantly increases the risk of endometrial cancer, pulmonary embolism and stroke, rendering the treatment based on aromatase inhibitors an interesting alternative, which demonstrate reduced frequency of the aforementioned adverse effects, though not without a high risk of loss in bone mineral density (BMD) and, conse‐ quently, fractures [160]. Raloxifen and toremifene demonstrates similar effectiveness in comparison to tamoxifene regarding reduction of risks in developing advanced and invasive breast cancer respectively. They also show evidence of lower incidence of venous thromboem‐

The aromatase enzyme is responsible for the conversion of androgens to estrogens and represent the primary source of estrogens in post-menopausal women. Accordingly, the aromatase inhibitors (AI) provide reduction of estrogen concentration within ER+ breast cancer cells. There are three generations of AI, which may also be classified as belonging to the type 1 (steroidal) and type 2 (non-steroidal) [27]. Aminoglutethimide is a 1st genera‐ tion nonsteroidal AI which was utilized in association to glucocorticoid in the treatment of breast cancer and is currently replaced by the following generations of AI. Formestane, a 2nd generation steroidal AI, administrated via intramuscular-injection, led to localized reac‐ tions. It also presents clinical benefits within the group of patients that experienced progres‐ sive disease after treatment with tamoxifen and nonsteroidal AI [25,165]. Exemestane is an irreversible 3rd generation orally administrated steroidal AI, which exhibits higher estro‐ gen deprivation effect in comparison to formestane in the treatment of ER+ breast cancer progressive cases previously treated with tamoxifen. Anastrozole and letrozole are 3rd generation nonsteroidal AI which have demonstrated improved results with respect to disease free survival, recurrence rate and time to recurrence when compared to tamoxifen. This observation regards early, advanced and metastatic ER+ breast cancer treatment, irrespective of functioning as a first line adjuvant or post-tamoxifen drug. Despite the aforementioned improved clinical outcome provided by 3rd generation AIs, further longterm studies should be conducted in order to assess whether its safety profiles are superior

Despite the increased number of therapeutic options, the cancer therapy remains a challenge for physicians and researchers, especially with regards to the tumor resistance. In this scenario, a better understanding about the molecular basis of cancer will enable the improvement and development of therapeutic strategies that allow an effective combat against this malignancy

unknown ER status [162].

**10.5. Aromatase inhibitors**

bolic events and endometrial cancer [163,164].

when compared to that of tamoxifen [164,166-170).

**11. Conclusion**

and better quality of life for patients.

Progestational agents, such as the agonists of the PR megestrol and megestrol acetate, have been used as second-line hormonal therapy for metastatic hormone-dependent breast cancer and in the management of endometrial carcinoma previously treated by surgery and radio‐ therapy [27].

### **10.3. Antiestrogens and antiandrogens**

Antiestrogens and antiandrogens inhibit the binding of the natural endogenous ligands with the estrogen and androgen receptors (ER; AR) respectively. Thus they act preventing exacer‐ bation of these receptors signaling pathways frequently observable in cancer cells. This fact lead to inhibition of cancer cells division [154, 155].

Fulvestrant is an antiestrogen approved by the FDA in 2002 for the treatment of hormone receptor positive metastatic breast cancer in post-menopausal women refractory to previous tamoxifen regimen [156]. Fulvestrant is a complete antagonist of the ER-alfa/ER-beta and inhibits estrogen signaling by promoting mainly the degradation of ER-alfa and PRs after binding to the ER [157]. The most observable side effects due to the usage of fulvestrant include hot flashes, thrombosis, joint disorders, pain and gastrointestinal events [158].

Flutamide, Bicalutamide and Nilutamide are non-steroidal antiandrogens introduced in the 1970s in order to preclude the unwanted effects caused by the nonselective profile of steroidal agents. These non-steroidal agents are only used in combination with other drugs, mostly with GnRH agonists, for the treatment of prostate cancer in order to counterbalance the effect of the released testosterone following GnRH administration. Bicalutamide has been recently approved in the European Union for the treatment of locally advanced prostate cancer and present the best schedule and adverse effects profiles. Toxic effects include hot flashes, hepatotoxicity, diarrhea, decreased libido and gynecomastia. Patients in treatment with nilulatamide may experience ocular alterations [155].

#### **10.4. Selective Estrogen Receptor Modulators (SERMs)**

Selective estrogen receptor modulators (SERMs) are tissue-selective compounds and depend‐ ing on the site of action, exhibit agonistic (bone, liver, brain, cardiovascular system), antago‐ nistic (brain, breast) and mixed agonist/antagonist (uterus) effects. This phenomenon occurs due to different ER subtypes expression throughout the body among other factors [159,160].

The currently SERMs approved by the FDA are tamoxifen, toremifene and raloxifen. Raloxifen is used in osteoporosis's treatment and prevention for postmenopausal women and reduction of invasive breast cancer's risk for women with osteoporosis or at increased risk of invasive breast cancer.

Tamoxifen is used in the treatment of metastatic breast cancer as well as in the adjuvant treatment of node-positive breast cancer. Additionally, tamoxifen demonstrates preventive effects in women at high-risk of developing breast cancer [161]. Toremifene is used in the treatment of metastatic breast cancer in postmenopausal women with ER+ or tumors with unknown ER status [162].

Due to its agonistic properties, tamoxifen significantly increases the risk of endometrial cancer, pulmonary embolism and stroke, rendering the treatment based on aromatase inhibitors an interesting alternative, which demonstrate reduced frequency of the aforementioned adverse effects, though not without a high risk of loss in bone mineral density (BMD) and, conse‐ quently, fractures [160]. Raloxifen and toremifene demonstrates similar effectiveness in comparison to tamoxifene regarding reduction of risks in developing advanced and invasive breast cancer respectively. They also show evidence of lower incidence of venous thromboem‐ bolic events and endometrial cancer [163,164].

### **10.5. Aromatase inhibitors**

one are mediated through the nuclear progesterone receptor (PR), which interacts with transcriptionalcoregulators,movesintonuclearaggregatesandregulatesgeneexpression[153].

Progestational agents, such as the agonists of the PR megestrol and megestrol acetate, have been used as second-line hormonal therapy for metastatic hormone-dependent breast cancer and in the management of endometrial carcinoma previously treated by surgery and radio‐

Antiestrogens and antiandrogens inhibit the binding of the natural endogenous ligands with the estrogen and androgen receptors (ER; AR) respectively. Thus they act preventing exacer‐ bation of these receptors signaling pathways frequently observable in cancer cells. This fact

Fulvestrant is an antiestrogen approved by the FDA in 2002 for the treatment of hormone receptor positive metastatic breast cancer in post-menopausal women refractory to previous tamoxifen regimen [156]. Fulvestrant is a complete antagonist of the ER-alfa/ER-beta and inhibits estrogen signaling by promoting mainly the degradation of ER-alfa and PRs after binding to the ER [157]. The most observable side effects due to the usage of fulvestrant include

Flutamide, Bicalutamide and Nilutamide are non-steroidal antiandrogens introduced in the 1970s in order to preclude the unwanted effects caused by the nonselective profile of steroidal agents. These non-steroidal agents are only used in combination with other drugs, mostly with GnRH agonists, for the treatment of prostate cancer in order to counterbalance the effect of the released testosterone following GnRH administration. Bicalutamide has been recently approved in the European Union for the treatment of locally advanced prostate cancer and present the best schedule and adverse effects profiles. Toxic effects include hot flashes, hepatotoxicity, diarrhea, decreased libido and gynecomastia. Patients in treatment with

Selective estrogen receptor modulators (SERMs) are tissue-selective compounds and depend‐ ing on the site of action, exhibit agonistic (bone, liver, brain, cardiovascular system), antago‐ nistic (brain, breast) and mixed agonist/antagonist (uterus) effects. This phenomenon occurs due to different ER subtypes expression throughout the body among other factors [159,160].

The currently SERMs approved by the FDA are tamoxifen, toremifene and raloxifen. Raloxifen is used in osteoporosis's treatment and prevention for postmenopausal women and reduction of invasive breast cancer's risk for women with osteoporosis or at increased risk of invasive

Tamoxifen is used in the treatment of metastatic breast cancer as well as in the adjuvant treatment of node-positive breast cancer. Additionally, tamoxifen demonstrates preventive effects in women at high-risk of developing breast cancer [161]. Toremifene is used in the

hot flashes, thrombosis, joint disorders, pain and gastrointestinal events [158].

therapy [27].

breast cancer.

**10.3. Antiestrogens and antiandrogens**

20 Cancer Treatment - Conventional and Innovative Approaches

lead to inhibition of cancer cells division [154, 155].

nilulatamide may experience ocular alterations [155].

**10.4. Selective Estrogen Receptor Modulators (SERMs)**

The aromatase enzyme is responsible for the conversion of androgens to estrogens and represent the primary source of estrogens in post-menopausal women. Accordingly, the aromatase inhibitors (AI) provide reduction of estrogen concentration within ER+ breast cancer cells. There are three generations of AI, which may also be classified as belonging to the type 1 (steroidal) and type 2 (non-steroidal) [27]. Aminoglutethimide is a 1st genera‐ tion nonsteroidal AI which was utilized in association to glucocorticoid in the treatment of breast cancer and is currently replaced by the following generations of AI. Formestane, a 2nd generation steroidal AI, administrated via intramuscular-injection, led to localized reac‐ tions. It also presents clinical benefits within the group of patients that experienced progres‐ sive disease after treatment with tamoxifen and nonsteroidal AI [25,165]. Exemestane is an irreversible 3rd generation orally administrated steroidal AI, which exhibits higher estro‐ gen deprivation effect in comparison to formestane in the treatment of ER+ breast cancer progressive cases previously treated with tamoxifen. Anastrozole and letrozole are 3rd generation nonsteroidal AI which have demonstrated improved results with respect to disease free survival, recurrence rate and time to recurrence when compared to tamoxifen. This observation regards early, advanced and metastatic ER+ breast cancer treatment, irrespective of functioning as a first line adjuvant or post-tamoxifen drug. Despite the aforementioned improved clinical outcome provided by 3rd generation AIs, further longterm studies should be conducted in order to assess whether its safety profiles are superior when compared to that of tamoxifen [164,166-170).

### **11. Conclusion**

Despite the increased number of therapeutic options, the cancer therapy remains a challenge for physicians and researchers, especially with regards to the tumor resistance. In this scenario, a better understanding about the molecular basis of cancer will enable the improvement and development of therapeutic strategies that allow an effective combat against this malignancy and better quality of life for patients.

### **Author details**

Isabella dos Santos Guimarães\*, Renata Dalmaschio Daltoé\*, Alice Laschuk Herlinger, Klesia Pirola Madeira, Taciane Ladislau, Iuri Cordeiro Valadão,

[10] Clowse ME, Behera MA, Anders CK, Copland S, Coffman CJ, Leppert PC, Bastian LA. Ovarian preservation by GnRH agonists during chemotherapy: a meta-analysis.

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 23

[11] Siddik ZH. Mechanism of action of cancer chemotherapeutic agents: DNA-interac‐ tive alkylating agents and antitumour platinum-based drugs. In The cancer hand‐

[12] Colvin ME, Sasaki JC, Tran NL. Chemical factors in the action of phosphoramidic mustard alkylating anticancer drugs: roles for computational chemistry. Current

[13] Corsi A, Calabresi F, Greco C. Comparative effects of cyclophosphamide and iso‐ phosphamide on Lewis lung carcinoma. British Journal of Cancer 1978;38: 631-633.

[14] Penel N, Van Glabbeke M, Marreaud S, Ouali M, Blay JY, Hohenberger P. Testing new regimens in patients with advanced soft tissue sarcoma: analysis of publications

[15] Voss MH, Feldman DR, Bosl GJ, Motzer RJ. A review of second-line chemotherapy and prognostic models for disseminated germ cell tumors. Hematology/Oncology

[16] Wasserman TH, Slavik M, Carter SK. Clinical comparison of the nitrosoureas. Cancer

[17] Marchesi F, Turriziani M, Tortorelli G, Avvisati G, Torino F, De Vecchis L. Triazene compounds: mechanism of action and related DNA repair systems. Pharmacological

[18] Neyns B, Tosoni A, Hwu WJ, Reardon DA. Dose-dense temozolomide regimens: an‐ titumor activity, toxicity, and immunomodulatory effects. Cancer 2010;116(12):

[19] Advani R. Optimal therapy of advanced Hodgkin lymphoma. American Society of

[20] Flaherty KT. Chemotherapy and targeted therapy combinations in advanced melano‐

[21] Rosenberg B, Vancamp L, Krigas T. Inhibition of cell division in Escherichia coli by electrolysis products from a platinum electrode. Nature 1965;205: 698-699.

[22] Desoize B. Metals and metal compounds in cancer treatment. Anticancer Research

[23] Boulikas T, Pantos A, Bellis E, Christofis P. Designing platinum compounds in can‐

cer: structures and mechanisms. Cancer Therapy 2007;5: 537-583.

Journal of Womens Health (Larchmt) 2009;18: 311-319.

Pharmaceutical Design 1999;5: 645-663.

Clinics of North America 2011;25: 557-576.

Hematology Education Program 2011;2011: 310-316.

ma. Clinical Cancer Research 2006;12: 2366-2370.

1975;36: 1258-1268.

2868-2877.

Research 2007;56: 275-287.

2004;24(3a): 1529-1544.

book. Edited by Alison M R. New Jersey: John Wiley & Sons 2002.

from the last 10 years. Annals of Oncology 2011;22: 1266-1272.

Paulo Cilas Morais Lyra Junior, Sarah Fernandes Teixeira, Gustavo Modesto Amorim, Diandra Zipinotti dos Santos, Karina Rangel Demuth and Leticia Batista Azevedo Rangel

Laboratory of Cellular and Molecular Biology of Human Cancer, Federal University of Es‐ pirito Santo, Brazil

\*These authors equally contributed to the elaboration of this chapter

### **References**


[10] Clowse ME, Behera MA, Anders CK, Copland S, Coffman CJ, Leppert PC, Bastian LA. Ovarian preservation by GnRH agonists during chemotherapy: a meta-analysis. Journal of Womens Health (Larchmt) 2009;18: 311-319.

**Author details**

pirito Santo, Brazil

**References**

1958;181(4613): 931.

2012; 142:0.

204.

Isabella dos Santos Guimarães\*, Renata Dalmaschio Daltoé\*, Alice Laschuk Herlinger,

Paulo Cilas Morais Lyra Junior, Sarah Fernandes Teixeira, Gustavo Modesto Amorim, Diandra Zipinotti dos Santos, Karina Rangel Demuth and Leticia Batista Azevedo Rangel

Laboratory of Cellular and Molecular Biology of Human Cancer, Federal University of Es‐

[1] Gilman A & Phillips FS. The Biological Actions and Therapeutic Applications of the

[3] Arnold H, Bourseaux F, Brock N. Chemotherapeutic action of a cyclic nitrogen mus‐ tard phosphamide ester (B 518-ASTA) in experimental tumours of the rat. Nature

[4] Friedman OM, Seligman AM. Preparation of N-phosphorylated derivatives of bis-Pchloroethylamine. Journal of the American Chemical Society 1954;76: 655-658.

[5] Emadi A, Jones RJ, Brodsky RA. Cyclophosphamide and cancer: golden anniversary.

[6] Brock N, Wilmanns H. Effect of a cyclic nitrogen mustard-phosphamidester on ex‐ perimentally induced tumors in rats; chemotherapeutic effect and pharmacological properties of B518 ASTA. Deutsche Medizinische Wochenschrift 1958;83: 453-458.

[7] Mey U, Hitz F, Lohri A, Pederiva S, Taverna C, Tzankov A, Meier O, Yeow K, Renner C. Diagnosis and treatment of diffuse large B-cell lymphoma. Swiss Medical Weekly

[8] Hillmen P. Using the biology of chronic lymphocytic leukemia to choose treatment.

[9] López-Tarruella S, Martín M. Recent advances in systemic therapy: advances in adju‐ vant systemic chemotherapy of early breast cancer. Breast Cancer Research 2009;11:

American Society of Hematology Education Program 2011;2011: 104-109.

B-Chloroethyl Amines and Sulfides. Science 1946;103(2675): 409-436.

[2] Haskell C M. Cancer Treatment. Philadelphia: Saunders; 1990.

Nature Reviews Clinical Oncology 2009;6: 638-647.

Klesia Pirola Madeira, Taciane Ladislau, Iuri Cordeiro Valadão,

22 Cancer Treatment - Conventional and Innovative Approaches

\*These authors equally contributed to the elaboration of this chapter


[24] Gore ME, Fryatt I, Wiltshaw E, Dawson T, Robinson BA & Calvert AH. Cisplatin/ carboplatin cross-resistance in ovarian cancer. British Journal of Cancer 1989;60: 767-769.

S, Rolski J, Goksel T, de Marinis F, Simms L, Sugarman KP, Gandara D. Phase III study comparing cisplatin plus gemcitabine with cisplatin plus pemetrexed in che‐ motherapy-naive patients with advanced-stage non-small-cell lung cancer. Journal of

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 25

[38] Adjei AA. Pharmacology and mechanism of action of pemetrexed. Clinical Lung

[39] Hitchings GH Jr. Nobel lecture in physiology or medicine - 1988. Selective inhibitors of dihydrofolate reductase. In Vitro Cellular Developmental Biology 1989;25(4):

[40] Galmarini CM, Mackey JR, Dumontet C. Nucleoside analogues and nucleobases in

[41] Stanczyk M, Sliwinski T, Trelinska J, Cuchra M, Markiewicz L, Dziki L, Bieniek A, Bielecka-Kowalska A, Kowalski M, Pastorczak A, Szemraj J, Mlynarski W, Majsterek I. Role of base-excision repair in the treatment of childhood acute lymphoblastic leu‐ kaemia with 6-mercaptopurine and high doses of methotrexate. Mutation Research

[42] Dervieux T, Blanco JG, Krynetski EY, Vanin EF, Roussel MF, Relling MV. Differing contribution of thiopurine methyltransferase to mercaptopurine versus thioguanine

[43] Elion GB. Nobel lecture in physiology or medicine - 1988. The purine path to chemo‐

[44] Karran P & Attard N. Thiopurines in current medical practice: molecular mecha‐ nisms and contributions to therapy-related cancer. Nature Review Cancer 2008;8(1):

[45] Plunkett W, Huang P, Gandhi V. Metabolism and action of fludarabine phosphate.

[46] Chun HG, Leyland-Jones B, Cheson BD. Fludarabine phosphate: a synthetic purine antimetabolite with significant activity against lymphoid malignancies. Journal of

[47] Yang SW, Huang P, Plunkett W, Becker FF, Chan JY. Dual mode of inhibition of puri‐ fied DNA ligase I from human cells by 9-beta-D-arabinofuranosyl-2-fluoroadenine

[48] Catapano CV, Perrino FW, Fernandes DJ. Primer RNA chain termination induced by 9-beta-D-arabinofuranosyl-2-fluoroadenine 5'-triphosphate. A mechanism of DNA

[49] Cheson BD, Vena DA, Foss FM, Sorensen JM. Neurotoxicity of purine analogs: a re‐

synthesis inhibition. Journal of Biological Chemistry 1993;268(10): 7179-7185.

view. Journal of Clinical Oncology 1994;12(10): 2216-2228.

triphosphate. The Journal of Biological Chemistry 1992;267(4): 2345-2349.

effects in human leukemic cells. Cancer Research 2001;61(15): 5810-5816

therapy. In Vitro Cell Development Biology 1989;25(4): 321-330.

cancer treatment. The Lancet Oncology 2002;3(7): 415-424.

Clinical Oncology 2008;26(21): 3543-3551.

Cancer 2004;5Suppl2: S51-55.

303-310.

24-36.

2012;741(1-2): 13-21.

Seminars Oncology 1990;17(5): 3-17.

Clinical Oncology 1991;9(1): 175-188.


S, Rolski J, Goksel T, de Marinis F, Simms L, Sugarman KP, Gandara D. Phase III study comparing cisplatin plus gemcitabine with cisplatin plus pemetrexed in che‐ motherapy-naive patients with advanced-stage non-small-cell lung cancer. Journal of Clinical Oncology 2008;26(21): 3543-3551.

[38] Adjei AA. Pharmacology and mechanism of action of pemetrexed. Clinical Lung Cancer 2004;5Suppl2: S51-55.

[24] Gore ME, Fryatt I, Wiltshaw E, Dawson T, Robinson BA & Calvert AH. Cisplatin/ carboplatin cross-resistance in ovarian cancer. British Journal of Cancer 1989;60:

[25] Hong WK, Bast Jr RC, Hait WN, Kufe DW, Pollock RE, Weichselbaum RR, Holland JF & Frei III E. Cancer Medicine 8. American Association for Cancer Research 2010.

[26] Saris CP, van de Vaart PJ, Rietbroek RC, Blommaert FA. In vitro formation of DNA adducts by cisplatin, lobaplatin and oxaliplatin in calf thymus DNA in solution and

[27] Brunton LL, Chabner BA & Knollmann BC. Goodman & Gilman's. The Pharmacolog‐

[28] Pasetto LM, D'Andrea MR, Brandes AA, Rossi E & Monfardini S. The development of platinum compounds and their possible combination. Critical Reviews in Oncolo‐

[29] Farber S, Diamond LK. Temporary remissions in acute leukemia in children pro‐ duced by folic acid antagonist, 4-aminopteroyl-glutamic acid. New England Journal

[30] Zhao R & Goldman ID. Resistance to antifolates. Oncogene 2003;22(47): 7431-7457.

[31] Chabner BA, Allegra CJ, Curt GA, Clendeninn NJ, Baram J, Koizumi S, Drake JC, Jo‐ livet J. Polyglutamation of methotrexate. Is methotrexate a prodrug? The Journal of

[32] Cho RC, Cole PD, Sohn KJ, Gaisano G, Croxford R, Kamen BA, Kim YI. Effects of fo‐ late and folylpolyglutamyl synthase modulation on chemosensitivity of breast cancer

[33] Fabre I, Fabre G, Goldman ID. Polyglutamylation, an important element in metho‐ trexate cytotoxicity and selectivity in tumor versus murine granulocytic progenitor

[34] Holmboe L, Andersen AM, Mørkrid L, Slørdal L, Hall KS. High dose methotrexate chemotherapy: pharmacokinetics, folate and toxicity in osteosarcoma patients. Brit‐

[35] Salliot C & Van der Heijde D. Long-term safety of methotrexate monotherapy in pa‐ tients with rheumatoid arthritis: a systematic literature research. Annals of the Rheu‐

[36] Buqué A, Muhialdin JS, Muñoz A, Calvo B, Carrera S, Aresti U, Sancho A, Rubio I, López-Vivanco G. Molecular mechanism implicated in Pemetrexed induced apopto‐

[37] Scagliotti GV, Parikh P, von Pawel J, Biesma B, Vansteenkiste J, Manegold C, Serwa‐ towski P, Gatzemeier U, Digumarti R, Zukin M, Lee JS, Mellemgaard A, Park K, Patil

in cultured human cells. Carcinogenesis 1996;17(12): 2763-2769.

ical Basis of Terapeutics. New York: McGraw-Hill Companies 2011.

767-769.

gy Hematology 2006;60: 59-75.

24 Cancer Treatment - Conventional and Innovative Approaches

of Medicine. 1948; 238(23):787-793.

Clinical Investigation 1985;76(3): 907-912.

matic Diseases 2009;68(7): 1100-1104.

cells. Molecular Cancer Therapy 2007;6(11): 2909-2920.

cells in vitro. Cancer Research. 1984;44(8): 3190-3195.

ish Journal of Clinical Pharmacology 2012;73(1): 106-114.

sis in human melanoma cells. Molecular Cancer 2012;11(1): 25.


[64] Jordan MA & Wilson L. Microtubules as a target for anticancer drugs. Nature Re‐

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 27

[65] Dumontet C & Jordan MA. Microtubule-binding agents: a dynamic field of cancer

[66] Kingston DG. Tubulin-interactive natural products as anticancer agents. Journal Nat‐

[67] Lucas DM, Still PC, Pérez LB, Grever MR & Kinghorn AD. Potential of Plant-Derived Natural Products in the Treatment of Leukemia and Lymphoma. Current Drug Tar‐

[68] Groninger E, Meeuwsen-de Boar T, Koopmans P, Uges D, Sluiter W, Veerman A, Kamps W, de Graaf S. Pharmacokinetics of vincristine monotherapy in childhood

[69] Rowinsky EK & Donehower RC. The clinical pharmacology and use of antimicrotu‐ bule agents in cancer chemotherapeutics. Pharmacology & Therapeutics 1991;52:

[70] Mano M. Vinorelbine in the management of breast cancer: New perspectives, revived role in the era of targeted therapy. Cancer Treatment Reviews 2006;32: 106-118 [71] Gralla RJ, Gatzemeier U, Gebbia V, Huber R, O'Brien M, & Puozzo C.Oral vinorel‐ bine in the treatment of non-small cell lung cancer: rationale and implications for pa‐

[72] Quasthoff S & Hartung HP. Chemotherapy-induced peripheral neuropathy. Journal

[73] Canta A, Chiorazzi A, Cavaletti G. Tubulin: a target for antineoplastic drugs into the cancer cells but also in the peripheral nervous system. Current Medicinal Chemistry

[74] Goa KL & Faulds D. Vinorelbine. A review of its pharmacological properties and

[75] Gottesman MM, Fojo T, Bates SE. Multidrug resistance in cancer: role of ATP-de‐

[76] Natarajan K, Senapati S. Understanding the basis of drug resistance of the mutants of αβ-tubulin dimer via molecular dynamics simulations. PLoS One 2012;7(8):e42351

[77] Gonzalez-Garay ML, Chang L, Blade K, Menick DR, Cabral F.A beta-tubulin leucine cluster involved in microtubule assembly and paclitaxel resistance. The Journal of Bi‐

clinical use in cancer chemotherapy. Drugs Aging 1994;5(3): 200-234.

pendent transporters. Nature Reviews Cancer 2002;2(1): 48-58.

acute lymphoblastic leukemia. Pediatric Research 2002;52(1): 113-118.

therapeutics. Nature Reviews Drug Discovery 2010;9(10): 790-803.

views Cancer 2004;4: 253-265.

ural Products 2009;72: 507-515.

tient management. Drugs 2007;67: 1403-1410.

ological Chemistry 1999;274(34): 23875-23882.

of Neurology 2002;249(1): 9-17.

2009;16(11): 1315-1324.

gets 2010;11: 812–822.

35-84.

1-13.


[64] Jordan MA & Wilson L. Microtubules as a target for anticancer drugs. Nature Re‐ views Cancer 2004;4: 253-265.

[50] Beutler E. Cladribine (2-chlorodeoxyadenosine). Lancet 1992;340(8825): 952-956.

1992;44(4): 459-477.

26 Cancer Treatment - Conventional and Innovative Approaches

ical strategies. Nature 2003;3: 330-338.

Anticancer Drugs 2001;12(8): 639-646.

10.1007/s00280-012-1974-z.

1016-1022.

Clinical Cancer Research 1999;5: 2289-2296.

nervous system. Journal of Biology 2008;7(4): 12.

[51] Klohs WD & Kraker AJ. Pentostatin: future directions. Pharmacological Reviews

[52] Longley DB, Harkin DP, Johnston PG. 5-Fluorouracil: Mechanisms of action and clin‐

[53] Lamont EB & Schilsky RL. The Oral Fluoropyrimidines in Cancer Chemotherapy.

[54] Han R, Yang YM, Dietrich J, Luebke A, Mayer-Pröschel M, Noble M. Systemic 5-fluo‐ rouracil treatment causes a syndrome of delayed myelin destruction in the central

[55] Stewart T, Pavlakis N, Ward M. Cardiotoxicity with 5-fluorouracil and capecitabine: more than just vasospastic angina. Internal Medicine Journal 2010;40(4): 303-307.

[56] Miwa M, Ura M, Nishida M, Sawada N, Ishikawa T, Mori K, Shimma N, Umeda I, Ishitsuka H. Design of a novel oral fluoropyrimidine carbamate, capecitabine, which generates 5-fluorouracil selectively in tumours by enzymes concentrated in human

[57] Johnston PG & Kaye S. Capecitabine: a novel agent for the treatment of solid tumors.

[58] Qiu MT, Ding XX, Hu JW, Tian HY, Yin R, Xu L. Fixed-dose rate infusion and stand‐ ard rate infusion of gemcitabine in patients with advanced non-small-cell lung can‐ cer: a meta-analysis of six trials. Cancer Chemotherapy and Pharmacology 2012; DOI:

[59] Hui YF & Reitz J. Gemcitabine: A cytidine analogue active against solid tumors.

[60] Kim KI, Huh IS, Kim IW, Park T, Ahn KS, Yoon SS, Yoon JH, Oh JM. Combined in‐ teraction of multi-locus genetic polymorphisms in cytarabine arabinoside metabolic pathway on clinical outcomes in adult acute myeloid leukaemia (AML) patients. Eu‐

[61] Hartford CM, Duan S, Delaney SM, Mi S, Kistner EO, Lamba JK, Huang RS, Dolan ME. Population-specific genetic variants important in susceptibility to cytarabine

[62] Johnson IS, Wright HF, Svoboda GH, Vlantis J. Antitumor principles derived from Vinca rosea Linn. I. Vincaleukoblastine and leurosine. Cancer Research 1960;20:

[63] Jordan MA, Thrower D, Wilson L. Mechanism of inhibition of cell proliferation by

American Journal of Health-System Pharmacy 1997;54: 162-170.

ropean Journal of Cancer 2012;DOI: 10.1016/j.ejca.2012.07.022.

arabinoside cytotoxicity. Blood 2009;113(10): 2145–2153.

vinca alkaloids. Cancer Research 1991;51(8): 2212-2222.

liver and cancer tissue. European Journal of Cancer 1998;34(8): 1274–1281.


[78] Burkhart CA, Kavallaris M, Band Horwitz S. The role of beta-tubulin isotypes in re‐ sistance to antimitotic drugs. Biochimica et Biophysica Acta (BBA) – Proteins and Proteomics 2001;1471(2): O1-9.

[92] Bode CJ, Gupta ML Jr, Reiff EA, Suprenant KA, Georg GI & Himes RH. Epothilone and paclitaxel: unexpected differences in promoting the assembly and stabilization of

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 29

[93] de Jonge M & Verweij J. The epothilone dilemma. Journal of Clinical Oncology

[94] Goodin S, Kane MP, Rubin EH. Epothilones: mechanism of action and biologic activi‐

[95] Wall ME, Wani MC, Cook CE, Palmer KH. Plant antitumor agents, I: the isolation and structure of camptothecin, a novel alkaloidal leukemia and tumor inhibitor from Camptotheca acuminate. Journal of the American Chemical Society 1966;88: 3888–

[96] Pommier Y. Topoisomerase I inhibitors: camptothecins and beyond. Nature Reviews

[97] Hsiang YH, Hertzberg R, Hecht S, Liu LF. Camptothecin induces protein-linked DNA breaks via mammalian DNA topoisomerase I. The Journal of Biological Chem‐

[98] Eng WK, Faucette L, Johnson RK, Sternglanz R. Evidence that DNA topoisomerase I is necessary for the cytotoxic effects of camptothecin. Molecular Pharmacology

[99] Jaxel C, Kohn KW, Wani MC, Wall ME, Pommier Y. Structure-activity study of the actions of camptothecin derivatives on mammalian topoisomerase I: evidence for a specific receptor site and a relation to antitumor activity. Cancer Research 1989;49(6):

[100] Grochow LB, Rowinsky EK, Johnson R, Ludeman S, Kaufmann SH, McCabe FL, Smith BR, Hurowitz L, DeLisa A, Donehower RC, et al. Pharmacokinetics and phar‐ macodynamics of topotecan in patients with advanced cancer. Drug Metabolism and

[101] Ormrod D, Spencer CM. Topotecan: a review of its efficacy in small cell lung cancer.

[102] Hartwell JL & Schrecker AW. Components of Podophyllin. V. The Constitution of Podophyllotoxin. Journal of the American Chemical Society 1951;73(6): 2909–2916.

[103] Lucas DM, Still PC, Pérez LB, Grever MR, Kinghorn AD. Potential of plant-derived natural products in the treatment of leukemia and lymphoma. Current Drug Targets

[104] Hande KR. Topoisomerase II inhibitors. Update on Cancer Therapeutics 2006;1: 3-15. [105] Hande KR. Etoposide: four decades of development of a topoisomerase II inhibitor.

yeast microtubules. Biochemistry 2002;41: 3870–3874.

ty. Journal of Clinical Oncology 2004;22(10): 2015-2025.

2005;23(36): 9048-9050.

Cancer 2006;6(10): 789-802.

1988;34(6): 755–760.

1465–1469.

istry 1985;260(27): 14873–14878.

Disposition 1992;20(5): 706-713.

European Journal of Cancer 1998;34: 1514-1521.

Drugs. 1999;58(3): 533-551.

2010;11(7): 812-822.

3890


[92] Bode CJ, Gupta ML Jr, Reiff EA, Suprenant KA, Georg GI & Himes RH. Epothilone and paclitaxel: unexpected differences in promoting the assembly and stabilization of yeast microtubules. Biochemistry 2002;41: 3870–3874.

[78] Burkhart CA, Kavallaris M, Band Horwitz S. The role of beta-tubulin isotypes in re‐ sistance to antimitotic drugs. Biochimica et Biophysica Acta (BBA) – Proteins and

[79] Zhang CC, Yang JM, White E, Murphy M, Levine A, Hait WN. The role of MAP4 ex‐ pression in the sensitivity to paclitaxel and resistance to vinca alkaloids in p53 mu‐

[80] Wani MC, Taylor HL, Wall ME, Coggon P, McPhail AT. Plant antitumor agents VI. The isolation and structure of taxol, a novel antileukemic and antitumor agent from Taxus brevifolia. Journal of the American Chemical Society 1971;93(9): 2325-2327. [81] Wall ME, Wani MC. Camptothecin and taxol: discovery to clinic--thirteenth Bruce F.

[82] Guenard D, Gueritte-Voegelein F, Potier P. Taxol and taxotere: discovery, chemistry, and structure-activity relationships. Accounts of Chemical Research 1993;26(4): 160–

[83] Rowinsky EK. The development and clinical utility of the taxane class of antimicrotu‐

[84] Horwitz SB, Cohen D, Rao S, et al. Taxol: mechanisms of action and resistance. Jour‐

[85] Haldar S, Chintapalli J, Croce CM. Taxol induces bcl-2 phosphorylation and death of

[86] Weiss RB, Donehower RC, Wiernik PH, Ohnuma T, Gralla RJ, Trump DL, Baker JR Jr, Van Echo DA, Von Hoff DD, Leyland-Jones B. Hypersensitivity reactions from

[87] Rowinsky EK, Donehower RC (1995) Paclitaxel (taxol). New England Journal of

[88] Miele E, Spinelli GP, Miele E, Tomao F, Tomao S. Albumin-bound formulation of pa‐ clitaxel (Abraxane ABI-007) in the treatment of breast cancer. International Journal of

[89] Rowinsky EK, Eisenhauer EA, Chaudhry V, Arbuck SG, Donehower RC. Clinical tox‐ icities encountered with paclitaxel (Taxol). Seminars in Oncology 1993;20(Suppl 3):

[90] Cortes J & Baselga J. Targeting the microtubules in breast cancer beyond taxanes: the

[91] Nettles JH, Li H, Cornett B, Krahn JM, Snyder JP, Downing KH. The binding mode of epothilone A on α,β-tubulin by electron crystallography. Science 2004;305: 866–869

bule chemotherapy agents. Annual Reviews Medicine 1997;48: 353-374.

nal of the National Cancer Institute 1994;15: 63–67.

prostate cancer cells. Cancer Research 1996; 56: 1253–1255.

taxol. Journal of Clinical Oncology 1990;8(7): 1263-1268.

Medicine 1995;332: 1004–1014

Nanomedicine 2009;4: 99-105.

epothilones. Oncologist 2007;12: 271-280.

Cain Memorial Award Lecture. Cancer Research 1995;55(4): 753-760.

Proteomics 2001;1471(2): O1-9.

28 Cancer Treatment - Conventional and Innovative Approaches

167.

1-15.

tant cells. Oncogene 1998;16(12): 1617-1624.


[106] Long BH, Casazza AM. Structure-activity relationships of VP-16 analogues. Cancer Chemotherapy Pharmacology 1994;34: 26-31.

[118] Umezawa H. Natural and artificial bleomycins: chemistry and antitumor activities.

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 31

[119] Chen J & Stubbe J. Bleomycins: towards better therapeutics. Nature Reviews Cancer

[120] Masetti R & Pession A. First-line treatment of acute lymphoblastic leukemia with pe‐

[121] Avramis VI. Asparaginases: A Successful Class of Drugs Against Leukemias and Lymphomas. Journal of Pediatric Hematology/Oncology 2011;33: 573-579

[122] Dinndorf PA, Gootenberg J, Cohen MH, Keegan P, Pazdur R. FDA drug approval summary: pegaspargase (oncaspar) for the first-line treatment of children with acute

[123] Hutson RG, Kitoh T, Moraga Amador DA, Cosic S, Schuster SM, Kilberg MS.Amino acid control of asparagine synthetase: relation to asparaginase resistance in human

[124] Albertsen BK, Schroder H, Jakobsen P, et al. Antibody formation during intravenous and intramuscular therapy with Erwinia asparaginase. Medical and Pediatric Oncol‐

[125] Dresler WFC, Stein R. Uber den Hydroxylharnstoff. Justus Liebigs Annalen der

[126] Rosenthal F, Wislicki L, Koller L. Uber die Bziehungen von schwertsen Blutgiften zu Abauprodukten des Einweisses: ein Beitrag zum Enstehungmechanismus der per‐

[127] Saban N, Bujak M. Hydroxyurea and hydroxamic acid derivatives as antitumor

[128] Madaan K, Kaushik D, Verma T. Hydroxyurea: a key player in cancer chemotherapy.

[129] Cokic VP, Smith RD, Beleslin-Cokic BB, Njoroge JM, Miller JL, Gladwin MT, Schecht‐ er AN. Hydroxyurea induces fetal hemoglobin by the nitric oxide-dependent activa‐ tion of soluble guanylyl cyclase. Journal of Clinical Investigation 2003;111(2): 231-239.

[130] Huang J, Kim-Shapiro DB, King SB. Catalase-mediated nitric oxide formation from

[131] Kennedy BJ, Smith LR, Goltz RW. Skin changes secondary to hydroxyurea therapy.

[132] Friedrich S, Raff K, Landthaler M, Karrer S. Cutaneous ulcerations on hands and heels secondary to long-term hydroxyurea treatment. European Journal of Dermatol‐

drugs. Cancer Chemotherapy and Pharmacology 2009;64(2): 213-221.

hydroxyurea. Journal of Medicinal Chemistry 2004;47(14): 3495-3501.

leukemia cells. The American Journal of Physiology 1997;272(5): 1691-1699.

lymphoblastic leukemia (ALL). The Oncologist 2007;12(8): 991-998.

Pure and Applied Chemistry 1971;28: 665–680.

gasparaginase. Biologics 2009;3: 359-368.

2005;5: 102-112.

ogy 2002;38: 310–316

Chemie 1869;150(2): 242-252.

nizosen Anemie. Klin Wochenschr 1928;7: 972-977.

Expert Review of Anticancer Therapy 2012;12(1): 19-29.

Archives of Dermatology 1975;111(2): 183-187.

ogy 2004;14(5): 343-346.


[118] Umezawa H. Natural and artificial bleomycins: chemistry and antitumor activities. Pure and Applied Chemistry 1971;28: 665–680.

[106] Long BH, Casazza AM. Structure-activity relationships of VP-16 analogues. Cancer

[107] Ross W, Rowe T, Glisson B, Yalowich J, Liu L. Role of topoisomerase II in mediating epipodophyllotoxin-induced DNA cleavage. Cancer Research 1984;44: 5857–5860.

[108] Osheroff N. Effect of antineoplastic agents on the DNA cleavage/religation reaction of eukaryotic topoisomerase II: inhibition of DNA religation by etoposide. Biochem‐

[109] Fan JR, Peng AL, Chen HC, Lo SC, Huang TH, Li TK. Cellular processing pathways contribute to the activation of etoposide-induced DNA damage responses. DNA Re‐

[110] Blanco JG, Dervieux T, Edick MJ, Mehta PK, Rubnitz JE, Shurtleff S, Raimondi SC, Behm FG, Pui CH, Relling MV. Molecular emergence of acute myeloid leukemia dur‐ ing treatment for acute lymphoblastic leukemia. Proceedings of National Acadamy

[111] Ratain MJ, Rowley JD. Therapy-related acute myeloid leukemia secondary to inhibi‐ tors of topoisomerase II: from the bedside to the target genes. Annals of Oncology

[112] Cortés-Funes H & Coronado C. Role of anthracyclines in the era of targeted therapy.

[113] Thorn CF, Oshiro C, Marsh S, Hernandez-Boussard T, McLeod H, Klein TE & Alt‐ man RB. Doxorubicin pathways: pharmacodynamics and adverse effects. Pharmaco‐

[114] Pai VB, Nahata MC. Cardiotoxicity of chemotherapeutic agents: incidence, treatment

[115] Batist G, Ramakrishnan G, Rao CS, Chandrasekharan A, Gutheil J, Guthrie T, Shah P, Khojasteh A, Nair MK, Hoelzer K, Tkaczuk K, Park YC, Lee LW. Reduced cardiotox‐ icity and preserved antitumour efficacy of liposome-encapsulated doxorubicin and cyclophosphamide compared with conventional doxorubicin and cyclophosphamide in a randomized, multicenter trial of metastatic breast cancer. Journal of Clinical On‐

[116] Trifilio SM, Rademaker AW, Newman D, Coyle K, Carlson-Leuer K, Mehta J, Altman J, Frankfurt O, Tallman MS. Mitoxantrone and etoposide with or without intermedi‐ ate dose cytarabine for the treatment of primary induction failure or relapsed acute

[117] Doggrell SA. Which drug combination for hormone-refractory prostate cancer?. Ex‐

of Sciences of the United States of America 2001;98(18): 10338-10343.

Chemotherapy Pharmacology 1994;34: 26-31.

istry 1989;28: 6157–6160.

30 Cancer Treatment - Conventional and Innovative Approaches

pair 2008;7(3): 452-463.

1992;3(2): 107-111.

Cardiovascular Toxicology 2007;7: 56-60.

genetics and Genomics 2011;21: 440-446.

cology 2001;19: 1444–1454.

and prevention. Drug Safety 2000;22(4): 263-302.

myeloid leukemia. Leukemia Research 2012;36: 394-396.

pert Opinion on Pharmacotherapy 2005;6: 667-670.


[133] Best PJ, Petitt RM. Multiple skin cancers associated with hydroxyurea therapy. Mayo Clinic Proceedings: Mayo Clinic 1998;73(10): 961-963.

[146] Major P. The use of zoledronic acid, a novel, highly potent bisphosphonate, for the treatment of hypercalcemia of malignancy. The Oncologist 2002;7: 481-491.

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 33

[148] Rogers TL & Holen I. Tumour macrophages as potential targets of bisphosphonates.

[149] Pozzi S & Raje N. The role of bisphosphonates in multiple myeloma: mechanisms,

[150] Richardson PG, Laubach JP, Schlossman RL, Ghobrial IM, Mitsiades CS, Rosenblatt J, Mahindra A, Raje N, Munshi N & Anderson KC.The Medical Research Council Mye‐ loma IX trial: the impact on treatment paradigms. European Journal of Haematology.

[151] Oakley RH & Cidlowski JA. Cellular processing of the glucocorticoid receptor gene and protein: new mechanisms for generating tissue-specific actions of glucocorti‐

[152] Schlossmacher G, Stevens A & White A. Glucocorticoid receptor-mediated apoptosis: mechanisms of resistance in cancer cells. Journal of Endocrinology 2011;211: 17-25.

[153] Scarpin KM, Graham JD, Mote PA & Clarke CL. Progesterone action in human tis‐ sues: regulation by progesterone receptor (PR) isoform expression, nuclear position‐ ing and coregulator expression. Nuclear Receptor Signaling 2009;7: e009.

www.nursa.org/article.cfm?doi=10.1621/nrs.07009 (accessed 20 October 2012).

[154] Heldring N, Pike A, Andersson S, Matthews J, Cheng G, Hartman J, Tujague M, Ström A, Treuter E, Warner M, Gustafsson JA. Estrogen receptors: how do they sig‐

[155] Chen Y, Clegg NJ, Scher HI. Anti-androgens and androgen-depleting therapies in prostate cancer: new agents for an established target. Lancet Oncology 2009;10(10):

[156] U.S. Food and Drug administration. FDA: Drug Databases: Drugs@FDA: Fulvestrant Label and Approval History: Labeling Revision (11/09/2012). www.accessda‐ ta.fda.gov/drugsatfda\_docs/label/2012/021344s019s020lbl.pdf. (accessed 20 Novem‐

[157] Robertson JF. Fulvestrant (Faslodex) -- how to make a good drug better. Oncologist

[158] Valachis A, Mauri D, Polyzos NP, Mavroudis D, Georgoulias V, Casazza G. Fulves‐ trant in the treatment of advanced breast cancer: a systematic review and meta-anal‐ ysis of randomized controlled trials. Critical Reviews in Oncology/Hematolology

nal and what are their targets. Physiological Reviews 2007;87(3): 905-931.

[147] Green JR. Antitumor effects of bisphosphonates. Cancer 2003;97(3 Suppl): 840-847.

Journal of Translational Medicine 2011;179: 177.

2012;88: 1-7.

981-991.

ber 2012)

2007;12(7): 774-784.

2010;73(3): 220-227.

side effects, and the future. The Oncologist 2011;16: 651-662.

coids. The Journal of Biological Chemistry 2011;286: 3177-3184.


[133] Best PJ, Petitt RM. Multiple skin cancers associated with hydroxyurea therapy. Mayo

[134] Sanchez-Palacios C, Guitart J. Hydroxyurea-associated squamous dysplasia. Journal

[135] Matthews SJ, McCoy C. Thalidomide: a review of approved and investigational uses.

[136] Bartlett JB, Dredge K, Dalgleish AG. The evolution of thalidomide and its IMiD de‐ rivatives as anticancer agents. Nature Reviews Cancer 2004;4(4): 314-322.

[137] FDA - U.S. Food and Drug Administration. FDA: Thalidomide (marketed as Thalo‐ mid) Information. www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInforma‐

[138] Bruera E, Neumann CM, Pituskin E, Calder K, Ball G, Hanson J. Thalidomide in pa‐ tients with cachexia due to terminal cancer: preliminary report. Annals of Oncology

[139] [139]. Gordon JN, Trebble TM, Ellis RD, Duncan HD, Johns T, Goggin PM. Thalido‐ mide in the treatment of cancer cachexia: a randomised placebo controlled trial. Gut

[140] [140]. Grover JK, Uppal G, Raina V. The adverse effects of thalidomide in relapsed and refractory patients of multiple myeloma. Annals of Oncology 2002;13(10):

[141] Dimopoulos MA, Eleutherakis-Papaiakovou V. Adverse effects of thalidomide ad‐ ministration in patients with neoplastic diseases. American Journal of Medicine

[142] Mohan R, Panda D. Kinetic stabilization of microtubule dynamics by estramustine is associated with tubulin acetylation, spindle abnormalities, and mitotic arrest. Cancer

[143] Ravery V, Fizazi K, Oudard S, Drouet L, Eymard JC, Culine S, Gravis G, Hennequin C, Zerbib M. The use of estramustine phosphate in the modern management of ad‐

[144] U.S. Food and Drug administration. FDA: FDA approves bortezomib (Velcade) for the treatment of patients with mantle cell lymphoma who have received at least one prior therapy. www.fda.gov/AboutFDA/CentersOffices/OfficeofMedicalProduct‐

[145] Chen D, Frezza M, Schmitt S, Kanwar J, Dou QP. Bortezomib as the first proteasome inhibitor anticancer drug: current status and future perspectives. Current Cancer

vanced prostate cancer. BJU International 2011;108(11): 1782-1786.

sandTobacco/CDER/ucm094929.htm (accessed 01 August 2012)

tionforPatientsandProviders/ucm107296.htm (accessed 01 August 2012)

Clinic Proceedings: Mayo Clinic 1998;73(10): 961-963.

Clinical Therapeutics 2003;25(2): 342-395.

32 Cancer Treatment - Conventional and Innovative Approaches

1999;10(7): 857-859.

2005; 54(4): 540-545.

2004;117(7): 508-515.

Research 2008;68(15): 6181-6189.

Drug Targets 2011;11(3): 239-253.

1636-1640.

of the American Academy of Dermatology 2004;51(2): 293-300.


[159] Lewis JS, Jordan VC. Selective estrogen receptor modulators (SERMs): mechanisms of anticarcinogenesis and drug resistance. Mutation Research 2005;591(1-2): 247-263.

[169] Regan MM, Neven P, Giobbie-Hurder A, Goldhirsch A, Ejlertsen B, Mauriac L, For‐ bes JF, Smith I, Láng I, Wardley A, Rabaglio M, Price KN, Gelber RD, Coates AS, Thürlimann B; BIG 1-98 Collaborative Group; International Breast Cancer Study Group (IBCSG). Assessment of letrozole and tamoxifen alone and in sequence for postmenopausal women with steroid hormone receptor-positive breast cancer: the BIG 1-98 randomised clinical trial at 8-1 years median follow-up. Lancet Oncology

Conventional Cancer Treatment http://dx.doi.org/10.5772/55282 35

2011;12(12): 1101-1108.


[169] Regan MM, Neven P, Giobbie-Hurder A, Goldhirsch A, Ejlertsen B, Mauriac L, For‐ bes JF, Smith I, Láng I, Wardley A, Rabaglio M, Price KN, Gelber RD, Coates AS, Thürlimann B; BIG 1-98 Collaborative Group; International Breast Cancer Study Group (IBCSG). Assessment of letrozole and tamoxifen alone and in sequence for postmenopausal women with steroid hormone receptor-positive breast cancer: the BIG 1-98 randomised clinical trial at 8-1 years median follow-up. Lancet Oncology 2011;12(12): 1101-1108.

[159] Lewis JS, Jordan VC. Selective estrogen receptor modulators (SERMs): mechanisms of anticarcinogenesis and drug resistance. Mutation Research 2005;591(1-2): 247-263.

[160] Pickar JH, MacNeil T, Ohleth K. SERMs: progress and future perspectives. Maturitas

[161] U.S. Food and Drug administration. FDA: Drug Databases: Drugs@FDA: Nolvadex Label and Approval History: Labeling Revision (03/17/2005). www.accessda‐ ta.fda.gov/drugsatfda\_docs/label/2005/17970s053lbl.pdf. (accessed 20 November

[162] U.S. Food and Drug administration. FDA: Drug Databases: Drugs@FDA: Fareston Label and Approval History: Labeling Revision (03/21/2011). www.accessda‐ ta.fda.gov/drugsatfda\_docs/label/2011/020497s006lbl.pdf. (accessed 20 November

[163] Vogel VG, Costantino JP, Wickerham DL, Cronin WM, Cecchini RS, Atkins JN, Bev‐ ers TB, Fehrenbacher L, Pajon ER Jr, Wade JL 3rd, Robidoux A, Margolese RG, James J, Lippman SM, Runowicz CD, Ganz PA, Reis SE, McCaskill-Stevens W, Ford LG, Jordan VC, Wolmark N; National Surgical Adjuvant Breast and Bowel Project (NSABP). Effects of tamoxifen vs raloxifene on the risk of developing invasive breast cancer and other disease outcomes: the NSABP Study of Tamoxifen and Raloxifene

[164] Cuzick J, Sestak I, Baum M, Buzdar A, Howell A, Dowsett M, Forbes JF; ATAC/ LATTE investigators. Effect of anastrozole and tamoxifen as adjuvant treatment for early-stage breast cancer: 10-year analysis of the ATAC trial. Lancet Oncology

[165] Johnston SR, Dowsett M. Aromatase inhibitors for breast cancer: lessons from the

[166] Dowsett M, Cuzick J, Ingle J, Coates A, Forbes J, Bliss J, Buyse M, Baum M, Buzdar A, Colleoni M, Coombes C, Snowdon C, Gnant M, Jakesz R, Kaufmann M, Boccardo F, Godwin J, Davies C, Peto R. Meta-analysis of breast cancer outcomes in adjuvant trials of aromatase inhibitors versus tamoxifen. Journal of Clinical Oncology

[167] Huiart L, Dell'Aniello S, Suissa S. Use of tamoxifen and aromatase inhibitors in a large population-based cohort of women with breast cancer. British Journal of Can‐

[168] Jakesz R, Jonat W, Gnant M, Mittlboeck M, Greil R, Tausch C, Hilfrich J, Kwasny W, Menzel C, Samonigg H, Seifert M, Gademann G, Kaufmann M, Wolfgang J; ABCSG and the GABG. Switching of postmenopausal women with endocrine-responsive ear‐ ly breast cancer to anastrozole after 2 years' adjuvant tamoxifen: combined results of

ABCSG trial 8 and ARNO 95 trial. Lancet 2005;366(9484): 455-462.

(STAR) P-2 trial. JAMA 2006;295(23): 2727-2741.

laboratory. Nature Reviews Cancer 2003;3(11): 821-831.

2010;67(2): 129-138.

34 Cancer Treatment - Conventional and Innovative Approaches

2010;11(12): 1135-1341

2010;28(3): 509-518

cer 2011;104(10): 1558-1563.

2012)

2012)

**Chapter 2**

**Target Cancer Therapy**

http://dx.doi.org/10.5772/55284

**1. Introduction**

Isabella S Guimarães, Sarah F Teixeira, Paulo CM Lyra-Júnior, Iuri C Valadão, Leticia BA Rangel and Alice L Herlinger

Additional information is available at the end of the chapter

Taciane Ladislau, Klesia P Madeira, Renata D Daltoé,

Over the past decade, cancer therapy has changed drastically by the introduction of the tar‐ get therapies, which focus on unique molecules present in tumors or protein whose expres‐ sion or function is enriched within the neoplastic tissue; the so called molecular targets. In this context, target therapies may include monoclonal antibodies, drugs or small inhibitors capable of inhibiting specific molecules, such as kinases. The major targets in cancer therapy are pathways directing cell growth, proliferation and survival, as well as, those interfering on tumors microenvironmental aspects, such as angiogenesis. On the other hand, an emerg‐ ing field on target therapy is the use of epigenetic drugs, which aim the restoration of the normal epigenetic landscape in cancer cells by targeting the epigenetic machinery of cells. Despite some major side effects associated to some target drugs, these therapies are well tol‐ erated by patients. Moreover, it bears the possibility of developing personal therapies to

Kinases are by definition proteins capable of catalyzing the transfer of the terminal phos‐ phate of ATP to substrates that contain, in most cases, a serine, threonine or tyrosine resi‐ due. The importance of targeting kinases to fight cancer relies on the central role that these molecules play on tumorigenesis, as uncontrolled tissue growth, and the capacity of cells to invade and metastasize [1]. Considering that, kinases involved in cell growth, division, mi‐

and reproduction in any medium, provided the original work is properly cited.

© 2013 Ladislau et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

each individual patient, which is considered the optimum choice in oncology.

**2. Kinases and their hole on tumor progression**

### **Chapter 2**

### **Target Cancer Therapy**

Taciane Ladislau, Klesia P Madeira, Renata D Daltoé, Isabella S Guimarães, Sarah F Teixeira, Paulo CM Lyra-Júnior, Iuri C Valadão, Leticia BA Rangel and Alice L Herlinger

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/55284

### **1. Introduction**

Over the past decade, cancer therapy has changed drastically by the introduction of the tar‐ get therapies, which focus on unique molecules present in tumors or protein whose expres‐ sion or function is enriched within the neoplastic tissue; the so called molecular targets. In this context, target therapies may include monoclonal antibodies, drugs or small inhibitors capable of inhibiting specific molecules, such as kinases. The major targets in cancer therapy are pathways directing cell growth, proliferation and survival, as well as, those interfering on tumors microenvironmental aspects, such as angiogenesis. On the other hand, an emerg‐ ing field on target therapy is the use of epigenetic drugs, which aim the restoration of the normal epigenetic landscape in cancer cells by targeting the epigenetic machinery of cells. Despite some major side effects associated to some target drugs, these therapies are well tol‐ erated by patients. Moreover, it bears the possibility of developing personal therapies to each individual patient, which is considered the optimum choice in oncology.

### **2. Kinases and their hole on tumor progression**

Kinases are by definition proteins capable of catalyzing the transfer of the terminal phos‐ phate of ATP to substrates that contain, in most cases, a serine, threonine or tyrosine resi‐ due. The importance of targeting kinases to fight cancer relies on the central role that these molecules play on tumorigenesis, as uncontrolled tissue growth, and the capacity of cells to invade and metastasize [1]. Considering that, kinases involved in cell growth, division, mi‐

© 2013 Ladislau et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

gration and differentiation, as well as, angiogenesis and metastasis have been exploited and targeted in therapeutic oncology [2].

growth factor 2 (HER2/neu), inhibiting the tumor driven cell growth. Its initial indication was for the treatment of patients with advanced or metastatic breast cancer (BC) whose tu‐ mors overexpress HER2 and who have received prior therapy including an anthracycline, a taxane, and trastuzumab. In 2012, the indications for lapatinib include the combined use of this drug with: capecitabine, for the treatment of patients with advanced or metastatic BC in the same conditions as mentioned above; letrozole for the treatment of postmenopausal women with hormone receptor positive metastatic BC that overexpress the HER2 receptor

Target Cancer Therapy

39

http://dx.doi.org/10.5772/55284

A variety of agents have been discovered to interfere with RAF kinases, each of which acting on different ways in order to block Raf protein expression, c-Ras/Raf interaction, Raf kinase activity, Raf's ATP-binding site, or the kinase activity of the Raf target protein MAPKK.

Among these, **sorafenib tyosilate**, a c-Raf inhibitors, has been approved by FDA in 2005. This bi-aryl urea was initially identified as an adenosine triphosphate competitive inhibitor of the c-Raf kinase. Sorafenib targets two kinase classes known to be involved in both tumor proliferation and angiogenesis [7]. The drug blocks the enzyme c-Raf kinase it self, a critical component of the Ras/Raf/MEK/ERK signaling pathway, which is responsible for control‐ ling cell division and proliferation. In addition, sorafenib inhibits the vascular endothelial growth factor receptor (VEGFR)-2/platelet-derived growth factor receptor (PDGFR)-beta sig‐ naling cascade, thereby blocking tumor growth and angiogenesis. Sorafenib has been evalu‐ ated as a single therapy agent and in combination with various chemotherapy drugs in a number of clinical trials [8-10]. At its first approval sorafenib tosylate was indicated for the treatment of adenois cyst carcinoma (ACC) patients; latter on, at the latest review, in 2012, the indication for the treatment of unresectable hepatocellular carcinoma (HCC) patients

Later on, in 2011, vemurafenib, which targets the mutated form of BRAF protein BRAFv600, was approved by FDA [11]. It has been approved for the treatment of patients with meta‐ static melanoma (MM) whose tumors presented the mutation, as detected by a FDA ap‐ proved test. However, it is not recommended for the treatment of MM patients who harbors

Raf inhibitors that are currently under clinical evaluation have shown promising signs of an‐ ti-cancer efficacy with a very tolerable safety profile [12], and will be further discussed on

Although MEK mutations are rare in human cancer, MEK inhibitors have been developed as a therapeutic strategy to combat B-RAF inhibitor resistance by targeting downstream effec‐ tors. To date, these MEK inhibitors have shown poor efficacy and activity in the clinic. How‐ ever, with the emergence of resistance to B-RAF therapy, and a higher than previously

the wild-type BRAF gene. It has been no review on vermurafenib label so far.

for whom hormonal therapy is indicated.

*3.1.2. Raf inhibitors*

was included.

this chapter.

*3.1.3. MEK inhibitors*

RAF/MEK/ERK and PI3K/AKT/mTOR are particularly important, as aberrant activation of these pathways is frequently observed in many types of cancers. Of interest, they are in‐ volved in chemoresistance to conventional chemotherapy, hormonal therapies and radiao‐ therapy. In addition, upstream elements of these signaling pathways, such as growth factors and growth factor receptors, as well as kinases exclusively found on cancer cells, as the ki‐ meric kinases derived from Philadelphia chromosome (Ph), can also be target for cancer therapy. Thus, inhibitors targeting any of these molecules can potentially suppress tumori‐ genesis and bypass resistance to conventional treatments to cancer [3, 4, 5].

### **3. Small molecule kinase inhibitors in cancer therapy**

Kinase inhibitors (KI) are divided into several classes based on the site they bind to at the enzyme. Types 1 and 2 bind to the ATP site of kinases, acting as ATP competitors. The dif‐ ference between these two types is that whereas type I inhibitors target the active conforma‐ tion of the kinase, type 2 bind to the inactive one. On the other hand, type 3 KI bind outside the ATP site, inhibiting kinases on an allosteric manner. This class of KI is usually more se‐ lective, since they bind to unique sequences from specific kinases. The forth class of KI are the covalent inhibitors, which irreversibly bind to the kinase active site, usually by reacting with a nucleophilic cystein residue [6]. KI already approved by the US Food and Drug Ad‐ ministration (FDA) will be discussed next, followed by KI currently under trial.

### **3.1. Kinase inhibitors approved by FDA for cancer treatment**

### *3.1.1. EGFR and HER2 kinase activity inhibitor*

**Gefitinib** was approved under FDA's accelerated approval regulation in 2003. It acts by in‐ hibiting the phosphorylation of a series of intracellular kinases associated with epidermal growth factor receptor (EGFR), among others. At its initial approval it was recommended for the treatment of patients with locally advanced or metastatic non-small cell lung carcino‐ ma (NSCLC) after the failure of both platinum-based and docetaxel chemotherapies. How‐ ever, in 2005, FDA published a labeling revision due to the failure demonstrated by gefitinib in increasing NSCLC patients' survival. Since this revision, gefitinib has only been prescri‐ bed for patients who are benefiting or have benefited from gefitinib.

In 2004, FDA approved **erlotinib**, which also inhibits the phosphorylation of EGFR-associat‐ ed TKs, for the treatment of locally advanced or metastatic NSCLC after failure of at least one prior chemotherapy regimen. On the next year, the indication for the use of erlotinib in combination with gemcitabine for the first-line treatment of patients with locally advanced, unresectable or metastatic pancreatic cancer (PC).

Different from the above mentioned KIs, **lapatinib**, approved by FDA in 2007, is a direct in‐ hibitor of the intracellular kinase domain of both EGFR and human growth epidermal growth factor 2 (HER2/neu), inhibiting the tumor driven cell growth. Its initial indication was for the treatment of patients with advanced or metastatic breast cancer (BC) whose tu‐ mors overexpress HER2 and who have received prior therapy including an anthracycline, a taxane, and trastuzumab. In 2012, the indications for lapatinib include the combined use of this drug with: capecitabine, for the treatment of patients with advanced or metastatic BC in the same conditions as mentioned above; letrozole for the treatment of postmenopausal women with hormone receptor positive metastatic BC that overexpress the HER2 receptor for whom hormonal therapy is indicated.

### *3.1.2. Raf inhibitors*

gration and differentiation, as well as, angiogenesis and metastasis have been exploited and

RAF/MEK/ERK and PI3K/AKT/mTOR are particularly important, as aberrant activation of these pathways is frequently observed in many types of cancers. Of interest, they are in‐ volved in chemoresistance to conventional chemotherapy, hormonal therapies and radiao‐ therapy. In addition, upstream elements of these signaling pathways, such as growth factors and growth factor receptors, as well as kinases exclusively found on cancer cells, as the ki‐ meric kinases derived from Philadelphia chromosome (Ph), can also be target for cancer therapy. Thus, inhibitors targeting any of these molecules can potentially suppress tumori‐

Kinase inhibitors (KI) are divided into several classes based on the site they bind to at the enzyme. Types 1 and 2 bind to the ATP site of kinases, acting as ATP competitors. The dif‐ ference between these two types is that whereas type I inhibitors target the active conforma‐ tion of the kinase, type 2 bind to the inactive one. On the other hand, type 3 KI bind outside the ATP site, inhibiting kinases on an allosteric manner. This class of KI is usually more se‐ lective, since they bind to unique sequences from specific kinases. The forth class of KI are the covalent inhibitors, which irreversibly bind to the kinase active site, usually by reacting with a nucleophilic cystein residue [6]. KI already approved by the US Food and Drug Ad‐

**Gefitinib** was approved under FDA's accelerated approval regulation in 2003. It acts by in‐ hibiting the phosphorylation of a series of intracellular kinases associated with epidermal growth factor receptor (EGFR), among others. At its initial approval it was recommended for the treatment of patients with locally advanced or metastatic non-small cell lung carcino‐ ma (NSCLC) after the failure of both platinum-based and docetaxel chemotherapies. How‐ ever, in 2005, FDA published a labeling revision due to the failure demonstrated by gefitinib in increasing NSCLC patients' survival. Since this revision, gefitinib has only been prescri‐

In 2004, FDA approved **erlotinib**, which also inhibits the phosphorylation of EGFR-associat‐ ed TKs, for the treatment of locally advanced or metastatic NSCLC after failure of at least one prior chemotherapy regimen. On the next year, the indication for the use of erlotinib in combination with gemcitabine for the first-line treatment of patients with locally advanced,

Different from the above mentioned KIs, **lapatinib**, approved by FDA in 2007, is a direct in‐ hibitor of the intracellular kinase domain of both EGFR and human growth epidermal

genesis and bypass resistance to conventional treatments to cancer [3, 4, 5].

ministration (FDA) will be discussed next, followed by KI currently under trial.

**3.1. Kinase inhibitors approved by FDA for cancer treatment**

bed for patients who are benefiting or have benefited from gefitinib.

*3.1.1. EGFR and HER2 kinase activity inhibitor*

unresectable or metastatic pancreatic cancer (PC).

**3. Small molecule kinase inhibitors in cancer therapy**

targeted in therapeutic oncology [2].

38 Cancer Treatment - Conventional and Innovative Approaches

A variety of agents have been discovered to interfere with RAF kinases, each of which acting on different ways in order to block Raf protein expression, c-Ras/Raf interaction, Raf kinase activity, Raf's ATP-binding site, or the kinase activity of the Raf target protein MAPKK.

Among these, **sorafenib tyosilate**, a c-Raf inhibitors, has been approved by FDA in 2005. This bi-aryl urea was initially identified as an adenosine triphosphate competitive inhibitor of the c-Raf kinase. Sorafenib targets two kinase classes known to be involved in both tumor proliferation and angiogenesis [7]. The drug blocks the enzyme c-Raf kinase it self, a critical component of the Ras/Raf/MEK/ERK signaling pathway, which is responsible for control‐ ling cell division and proliferation. In addition, sorafenib inhibits the vascular endothelial growth factor receptor (VEGFR)-2/platelet-derived growth factor receptor (PDGFR)-beta sig‐ naling cascade, thereby blocking tumor growth and angiogenesis. Sorafenib has been evalu‐ ated as a single therapy agent and in combination with various chemotherapy drugs in a number of clinical trials [8-10]. At its first approval sorafenib tosylate was indicated for the treatment of adenois cyst carcinoma (ACC) patients; latter on, at the latest review, in 2012, the indication for the treatment of unresectable hepatocellular carcinoma (HCC) patients was included.

Later on, in 2011, vemurafenib, which targets the mutated form of BRAF protein BRAFv600, was approved by FDA [11]. It has been approved for the treatment of patients with meta‐ static melanoma (MM) whose tumors presented the mutation, as detected by a FDA ap‐ proved test. However, it is not recommended for the treatment of MM patients who harbors the wild-type BRAF gene. It has been no review on vermurafenib label so far.

Raf inhibitors that are currently under clinical evaluation have shown promising signs of an‐ ti-cancer efficacy with a very tolerable safety profile [12], and will be further discussed on this chapter.

### *3.1.3. MEK inhibitors*

Although MEK mutations are rare in human cancer, MEK inhibitors have been developed as a therapeutic strategy to combat B-RAF inhibitor resistance by targeting downstream effec‐ tors. To date, these MEK inhibitors have shown poor efficacy and activity in the clinic. How‐ ever, with the emergence of resistance to B-RAF therapy, and a higher than previously thought frequency of somatic MEK mutations, these inhibitors are finding renewed clinical use [13].

reduction of protein synthesis and cell proliferation, also inhibit cell-cycle progression and angiogenesis, and promote apoptosis. Despite this positive action against cancer cells, these compounds, when inhibiting only mTORC1, lead to relieve negative feedback loop from S6K1 to IRS-1 resulting in PI3K/AKT pathway activation, and, consequently, could promote

Target Cancer Therapy

41

http://dx.doi.org/10.5772/55284

Temsirolimus and everolimus have been approved by FDA for the treatment of renal cell carcinoma (RCC). Everolimus has been approved for pancreatic neuroendocrine tumors, and recently for HER2-negative BC in combination with exemestane, after letrozole or anas‐ trozole treatment fails. These antineoplastic agents have been investigated in clinical trials for malignancies from many tissues, including breast, gynecologic, gastrointestinal, lung and melanoma, alone or in association with hormonal therapies, EGFR inhibitors, and cyto‐

The efficacy of rapalogs is partially limited by compensatory mechanism of mTOR activation driven by the loss of negative feedback and because mTOR can be regulated by other signaling pathways such as Ras/Raf/MEK/ERK. Thereby, the inhibition of this pathway alone provides a transient benefit that may result in treatment resistance. It has already been shown the benefits of using mTOR inhibitors in combination with anti-insulin-like growth factor 1 receptor (IGF-1R) monoclonal antibodies. Thus, in order to overcome possible mechanisms of resistance, it would be interesting to establish therapeutic schemes that use combinations of different drugs [4, 27]. Inhibitors of mTOR (TORKinhibs) are still under development/trial, as

well as the dual mTOR/PI3K inhibitors and will be discussed further on this chapter.

In 2003, FDA approved **imatinib mesylate**, a Bcr-Abl fusion tyrosine kinase, leading to impaired proliferation and apoptosis induction of cancer cells. Its indications were for newly diagnosed adult patients with Ph chromosome positive chronic myelogeneous leukemia (CML) in chronic phase, as well as for patients with CML in blast crisis, accelerated phase, or in chronic phase after failure of interferon (IFN)-alfa therapy. Apart from that, imatinib mesylate was also indicated for the treatment of patients with c-Kit positive unresected and/or metastatic malignant gastrointestinal stroma tumors (GIST). The most recent FDA revision on this drug label, from 2012, indicates imatinib mesylate for the treatment of all diseases mentioned above, as well as for: adult patients with relapsed or refractory Ph chromosome positive acute lymphoblastic leukemia (ALL); adult patients with myelodys‐ plastic/myeloproliferative diseases (MDS/MP) associated with PDGFR gene re-arrangements; adult patients with aggressive systemic mastocytosis (ASM) without the D816V c-Kit mutation or with c-Kit mutational status unknown; adult patients with hypereosinophilic syndrome (HES) and/or chronic eosinophilic leukemia (CEL) who have the FIP1L1PDGFRα fusion kinase (mutational analysis or FISH demonstration of CHIC2 allele deletion) and for patients with HES and/or CEL who are FIP1L1-PDGFRα fusion kinase negative or unknown status; adult patients with unresectable, recurrent and/or metastatic dermatofibrosarcoma protuberans (DFSP); and, adjuvant treatment of adult patients following complete gross resection of c-Kit

cell survival and chemoresistance [21, 25].

*3.1.5. Ph chromosome-related kinase inhibitors.*

toxic drugs [3, 19, 26, 27].

positive GIST.

Several MEK inhibitors have been identified: PD184352 (CI-1040), Selumetinib (AZD6244, ARRY-142886), PD0325901, XL518, GSK1120212 (JTP-74057), ARRY-438162. Worth noticing, most of the known MEK inhibitors are noncompetitive (ie, they do not bind to the ATP– binding site of the kinase) [14]. Despite ATP-biding pockets are highly conserved among hu‐ man kinases [15], structural analysis of demonstrates tha it harbors a unique site adjacent to the ATP binding site [16]. Thus, biding of inhibitos to this unique MEK site explain the high degree of specificity of the MEK inhibitors compared to other kinase inhibitors with compet‐ itive activity.

PD184352 is an orally active highly selective and potent chemical inhibitor of MEK1/2 and was the first MEK inhibitor to enter clinical trials. Selumetinib is the second MEK inhibitor to go into clinical trial after the first MEK inhibitor, CI-1040, demonstrated poor clinical effi‐ cacy. Selumetinib is a benzimidazole derivative with reported nanomolar activity against the purified MEK1 enzyme. Through a series of studies using preclinical cell cultures and animal models, it was shown that Selumetinib suppresses the growth of melanoma cells through the induction of cytostasis, but Selumetinib has a limited ability to induce apoptosis or block angiogenesis [17,18].

### *3.1.4. mTOR inhibitors*

**Rapamycin**, the canonical mTOR inhibitor, was identified in 1975 as a potent antifungal iso‐ lated from *Streptomyces hygroscopicus*, nowadays it is recognized for its immunosuppressive and antitumor activities. However, rapamycin has limited bioavailability duo to its poor aqueous solubility. In an effort to improve its pharmacokinetic characteristics, several rapa‐ mycin analogues, named **rapalogs**, have been developed, such the first generation mTOR in‐ hibitors **temsirolimus**, **everolimus**, and **ridaforolimus** [19-21].

In mammalian cells, members of this pharmacological class associate with the intracellular receptor FK506 binding protein 12 (FKBP12). Then, this complex interacts with FKBP12-ra‐ pamycin binding (FRB) domain, performing an allosteric mechanism of inhibition of mam‐ malian target of rapamycin (mTOR) kinase activity. Traditionally the rapalogs inhibit only mTOR complex (mTORC) 1, probably because FRB domain is occluded in mTORC2. How‐ ever, some studies have shown that these compounds are able to disrupt mTORC2 in a dose-, time- and cell type-dependent manner [20, 22]. A possible mechanism by which rapa‐ mycin and rapalogs could inhibit mTORC2 would be that rapamycin- or rapalogs-FKBP12 complexes would interact with newly synthesized mTOR molecules. In turn, this interaction would prevent mTOR interaction with RICTOR, inhibiting mTORC2. Indeed, it has been shown that prolonged treatment of cancer cells with rapamycin can promote its binding to mTOR before mTORC2 assembly, and subsequently inhibit Akt signaling [23]. In addition, treatment with temsirolimus or everolimus in acute myeloid leukemia (AML) cell lines blocked mTORC1 as well mTORC2 assembly [24]. In this way, rapalogs inhibit the signal transduction through the mTORCs downstream effectors, as 4E-BP1 and S6K1, resulting in reduction of protein synthesis and cell proliferation, also inhibit cell-cycle progression and angiogenesis, and promote apoptosis. Despite this positive action against cancer cells, these compounds, when inhibiting only mTORC1, lead to relieve negative feedback loop from S6K1 to IRS-1 resulting in PI3K/AKT pathway activation, and, consequently, could promote cell survival and chemoresistance [21, 25].

Temsirolimus and everolimus have been approved by FDA for the treatment of renal cell carcinoma (RCC). Everolimus has been approved for pancreatic neuroendocrine tumors, and recently for HER2-negative BC in combination with exemestane, after letrozole or anas‐ trozole treatment fails. These antineoplastic agents have been investigated in clinical trials for malignancies from many tissues, including breast, gynecologic, gastrointestinal, lung and melanoma, alone or in association with hormonal therapies, EGFR inhibitors, and cyto‐ toxic drugs [3, 19, 26, 27].

The efficacy of rapalogs is partially limited by compensatory mechanism of mTOR activation driven by the loss of negative feedback and because mTOR can be regulated by other signaling pathways such as Ras/Raf/MEK/ERK. Thereby, the inhibition of this pathway alone provides a transient benefit that may result in treatment resistance. It has already been shown the benefits of using mTOR inhibitors in combination with anti-insulin-like growth factor 1 receptor (IGF-1R) monoclonal antibodies. Thus, in order to overcome possible mechanisms of resistance, it would be interesting to establish therapeutic schemes that use combinations of different drugs [4, 27]. Inhibitors of mTOR (TORKinhibs) are still under development/trial, as well as the dual mTOR/PI3K inhibitors and will be discussed further on this chapter.

### *3.1.5. Ph chromosome-related kinase inhibitors.*

thought frequency of somatic MEK mutations, these inhibitors are finding renewed clinical

Several MEK inhibitors have been identified: PD184352 (CI-1040), Selumetinib (AZD6244, ARRY-142886), PD0325901, XL518, GSK1120212 (JTP-74057), ARRY-438162. Worth noticing, most of the known MEK inhibitors are noncompetitive (ie, they do not bind to the ATP– binding site of the kinase) [14]. Despite ATP-biding pockets are highly conserved among hu‐ man kinases [15], structural analysis of demonstrates tha it harbors a unique site adjacent to the ATP binding site [16]. Thus, biding of inhibitos to this unique MEK site explain the high degree of specificity of the MEK inhibitors compared to other kinase inhibitors with compet‐

PD184352 is an orally active highly selective and potent chemical inhibitor of MEK1/2 and was the first MEK inhibitor to enter clinical trials. Selumetinib is the second MEK inhibitor to go into clinical trial after the first MEK inhibitor, CI-1040, demonstrated poor clinical effi‐ cacy. Selumetinib is a benzimidazole derivative with reported nanomolar activity against the purified MEK1 enzyme. Through a series of studies using preclinical cell cultures and animal models, it was shown that Selumetinib suppresses the growth of melanoma cells through the induction of cytostasis, but Selumetinib has a limited ability to induce apoptosis

**Rapamycin**, the canonical mTOR inhibitor, was identified in 1975 as a potent antifungal iso‐ lated from *Streptomyces hygroscopicus*, nowadays it is recognized for its immunosuppressive and antitumor activities. However, rapamycin has limited bioavailability duo to its poor aqueous solubility. In an effort to improve its pharmacokinetic characteristics, several rapa‐ mycin analogues, named **rapalogs**, have been developed, such the first generation mTOR in‐

In mammalian cells, members of this pharmacological class associate with the intracellular receptor FK506 binding protein 12 (FKBP12). Then, this complex interacts with FKBP12-ra‐ pamycin binding (FRB) domain, performing an allosteric mechanism of inhibition of mam‐ malian target of rapamycin (mTOR) kinase activity. Traditionally the rapalogs inhibit only mTOR complex (mTORC) 1, probably because FRB domain is occluded in mTORC2. How‐ ever, some studies have shown that these compounds are able to disrupt mTORC2 in a dose-, time- and cell type-dependent manner [20, 22]. A possible mechanism by which rapa‐ mycin and rapalogs could inhibit mTORC2 would be that rapamycin- or rapalogs-FKBP12 complexes would interact with newly synthesized mTOR molecules. In turn, this interaction would prevent mTOR interaction with RICTOR, inhibiting mTORC2. Indeed, it has been shown that prolonged treatment of cancer cells with rapamycin can promote its binding to mTOR before mTORC2 assembly, and subsequently inhibit Akt signaling [23]. In addition, treatment with temsirolimus or everolimus in acute myeloid leukemia (AML) cell lines blocked mTORC1 as well mTORC2 assembly [24]. In this way, rapalogs inhibit the signal transduction through the mTORCs downstream effectors, as 4E-BP1 and S6K1, resulting in

hibitors **temsirolimus**, **everolimus**, and **ridaforolimus** [19-21].

use [13].

40 Cancer Treatment - Conventional and Innovative Approaches

itive activity.

or block angiogenesis [17,18].

*3.1.4. mTOR inhibitors*

In 2003, FDA approved **imatinib mesylate**, a Bcr-Abl fusion tyrosine kinase, leading to impaired proliferation and apoptosis induction of cancer cells. Its indications were for newly diagnosed adult patients with Ph chromosome positive chronic myelogeneous leukemia (CML) in chronic phase, as well as for patients with CML in blast crisis, accelerated phase, or in chronic phase after failure of interferon (IFN)-alfa therapy. Apart from that, imatinib mesylate was also indicated for the treatment of patients with c-Kit positive unresected and/or metastatic malignant gastrointestinal stroma tumors (GIST). The most recent FDA revision on this drug label, from 2012, indicates imatinib mesylate for the treatment of all diseases mentioned above, as well as for: adult patients with relapsed or refractory Ph chromosome positive acute lymphoblastic leukemia (ALL); adult patients with myelodys‐ plastic/myeloproliferative diseases (MDS/MP) associated with PDGFR gene re-arrangements; adult patients with aggressive systemic mastocytosis (ASM) without the D816V c-Kit mutation or with c-Kit mutational status unknown; adult patients with hypereosinophilic syndrome (HES) and/or chronic eosinophilic leukemia (CEL) who have the FIP1L1PDGFRα fusion kinase (mutational analysis or FISH demonstration of CHIC2 allele deletion) and for patients with HES and/or CEL who are FIP1L1-PDGFRα fusion kinase negative or unknown status; adult patients with unresectable, recurrent and/or metastatic dermatofibrosarcoma protuberans (DFSP); and, adjuvant treatment of adult patients following complete gross resection of c-Kit positive GIST.

**Dasatinib** is a KI of Bcr-Abl, SRC family, c-Kit, ephrin type-A receptor 2 (EPHA2) and PDGFRβ developed to overcome the imatinib-resistance observed in relapsed patients with accelerated phase or blast crisis phase CML [28]. It was approved by FDA in 2006 and is pre‐ dicted, based on modeling studies, to bind to multiple conformations of ABL kinase. It was initially approved for the treatment of patients with chronic, accelerated, myeloid or lym‐ phoid blast phase CML with resistance or intolerance to prior therapy including imatinib mesylate, as well as for the treatment of adults with Ph chromosome-positive ALL resistant or intolerant to prior therapy. The 2012 label review for this drug also includes its indication for the treatment of newly diagnosed adults with Ph chromosome-positive CML in chronic phase.

In early 2012, the VEGFR-1, -2 and -3 inhibitor **axitinib** was approved by FDA. This KI was capable of decreasing VEGF-mediated endothelial cell proliferation and growth both in vitro and in animal models. It is indicated for the treatment of advanced RCC patients after fail‐

Target Cancer Therapy

43

http://dx.doi.org/10.5772/55284

One of the most promising KI under trial is PKC412/midostaurin. It is a N-Benzoil deriva‐ tive capable of inhibiting classical protein kinase C (PKC) α, β, γ and the calcium-dependent PKCs δ, ε, η, as well as TK pathways [29]. In 2001, Propper and colleagues published a phase I and pharmacokinetics study on this compound [30]. This study engaged 32 subjects with different types of tumor, which were either refractory to conventional therapy or unre‐ sponsive to standard treatment, exposed to seven doses of PKC412/midostaurin (12.5 mg/day – 300 mg/day). From this study it was concluded the PKC412/midostaurin has had as main toxicity nausea/vomiting and fatigue, with significant side effects as diarrhea, ano‐ rexia, and headache. A dose-related suppression on circulating lymphocyte and monocyte number was observed after 28 days of treatment. The overall conclusion of this work was that PKC412/midostaurin at 150mg/day would be well tolerated chronically. Currently, 7 ac‐ tive clinical trials using PKC412/midostaurin as single drug or in combination with others can be assessed at the Clinical Trial Search engine from National Cancer Institute [31], as

Among studies using PKC412/midostaurin in combination with other drugs, two trials from Novartis (CPKC412A2114 and CPCK412AUS06T) evaluate the combined therapy of PKC412/midostaurin with the epigenetic drugs 5-azacytidine and decitabine, respectively. The first trial has been carried out with refractory or relapsed ALL and MDS patients' under 18 years old; the second has been carried out with newly diagnosed or relapsed AML pa‐ tients over 60 years old. Also from Novartis, a trial (NCT01477606) evaluates PKC412/ midostaurin in several combinations with the epigenetic drug cytarabine and the anthracy‐ cline daunorubicin, or as single agent, for the treatment of AML patients which express the RTK FLT3-ITD. From the Washington University of Medicine, a study (NCT01161550) eval‐ uated the combination of PKC412/midostaurin with either epigenetic drug cladribine or cy‐ tarabine in AML patients. Furthermore, PKC412/midostaurin has been evaluated on a collaborative trial (NCT01174888) from Novartis and Millennium Pharmaceuticals, Inc. in combination with bortezomib (a proteasome inhibitor), mitoxantrone hydrochloride (an an‐ thracenedione), etoposide (a topoisomerase inhibitor) or cytarabine (an epigenetic drug) for the treatment of patients with relapsed or refractory AML. Finally, PKC412/midostaurin has been tested in combination with radiation therapy and 5-fluorouracil for the treatment of patients with advanced rectal cancer in a study (NCT01282502) sponsored by the Massachu‐ setts General Hospital. As a single agent, PKC412/midostaurin has been tested by Novartis (NCT00866281) for the treatment of relapsed or refractory pediatric patients with AML and

**3.2. Kinase inhibitor currently under development or in clinical trial**

well as, at the U.S. National Institute of Health clinical trial database [32].

ure of previous systemic therapy.

*3.2.1. The PKC inhibitor PKC412/Midostaurin*

**Nilotinib hydrochloride monohydrate** was approved by FDA in 2007 for the treatment of chronic and accelerated phase Ph chromosome-positive CML adult patients which have de‐ veloped resistance or intolerance to prior therapy that included imatinib. In 2012, apart from these previous indications, nilotinib hydrochloride monohydrate has also been indicated for the treatment of newly diagnosed adult patients with Ph chromosome-positive CML in chronic phase.

#### *3.1.6. Multi-kinase inhibitors*

In 2006 FDA approved **sunitinib malate**, a multi-kinase inhibitor targeting several receptor tyrosine kinases (RTK), such as PDGFR-α and -β, VEGFR-1,-2 and -3, c-Kit, Fms-like tyro‐ sine kinase-3 (FLT3), colony stimulating factor receptor Type 1 (CSF-1R) and the glial cellline derived neurotrophic factor receptor (RET). At its first approval, sunitinib malate was indicated for the treatment of GIST after disease progression or intolerance to imatinib me‐ sylate; and, for the treatment of advanced RCC, this based on the partial response rates and duration of responses observed for this drug. On the latest FDA review on sunitinib malate indications, in 2012, it was included the indication for the treatment of progressive, well-dif‐ ferentiated pancreatic neuroendocrine tumors (NET) in patients with unresectable locally advanced or metastatic disease.

In 2009, FDA approved the multi-kinase inhibitor **pazopanib hydrochloride** targeting VEGFR-1,-2 and -3, PDGFR-α and –β, fibroblast growth factor receptor (FGFR)-1 and -3, c-Kit, interleukin -2 receptor inducible T-cell kinase (Itk), leukocyte-specific protein kinase (Lck), and transmembrane glycoprotein receptor tyrosine kinase (c-Fms). At its first appro‐ val, pazopanib hydrochloride was indicated for the treatment of RCC patients, and at its lat‐ est label review, in 2012, it was also indicated for the treatment of patients with advanced soft tissue sarcoma (STS) who have received prior chemotherapy, except for patients with adipocytic STS or GIST, for which pazopanib hydrochloride's efficacy has not been proved.

During the year of 2011, two KIs with different targets and indications have been approved by FDA. Firstly, **vandetanib** a KI with multiple targets, including VEGFR and EGFR, has been approved for the treatment of symptomatic or progressive medullary thyroid cancer (MTC) in patients with unresectable locally advanced or metastatic disease. Also, **crizotinib** was approved for the treatment of patients with anaplasic lymphoma kinase (ALK) -positive locally advanced or metastatic NSCLC. There was no indication review for this drug so far.

In early 2012, the VEGFR-1, -2 and -3 inhibitor **axitinib** was approved by FDA. This KI was capable of decreasing VEGF-mediated endothelial cell proliferation and growth both in vitro and in animal models. It is indicated for the treatment of advanced RCC patients after fail‐ ure of previous systemic therapy.

### **3.2. Kinase inhibitor currently under development or in clinical trial**

### *3.2.1. The PKC inhibitor PKC412/Midostaurin*

**Dasatinib** is a KI of Bcr-Abl, SRC family, c-Kit, ephrin type-A receptor 2 (EPHA2) and PDGFRβ developed to overcome the imatinib-resistance observed in relapsed patients with accelerated phase or blast crisis phase CML [28]. It was approved by FDA in 2006 and is pre‐ dicted, based on modeling studies, to bind to multiple conformations of ABL kinase. It was initially approved for the treatment of patients with chronic, accelerated, myeloid or lym‐ phoid blast phase CML with resistance or intolerance to prior therapy including imatinib mesylate, as well as for the treatment of adults with Ph chromosome-positive ALL resistant or intolerant to prior therapy. The 2012 label review for this drug also includes its indication for the treatment of newly diagnosed adults with Ph chromosome-positive CML in chronic

**Nilotinib hydrochloride monohydrate** was approved by FDA in 2007 for the treatment of chronic and accelerated phase Ph chromosome-positive CML adult patients which have de‐ veloped resistance or intolerance to prior therapy that included imatinib. In 2012, apart from these previous indications, nilotinib hydrochloride monohydrate has also been indicated for the treatment of newly diagnosed adult patients with Ph chromosome-positive CML in

In 2006 FDA approved **sunitinib malate**, a multi-kinase inhibitor targeting several receptor tyrosine kinases (RTK), such as PDGFR-α and -β, VEGFR-1,-2 and -3, c-Kit, Fms-like tyro‐ sine kinase-3 (FLT3), colony stimulating factor receptor Type 1 (CSF-1R) and the glial cellline derived neurotrophic factor receptor (RET). At its first approval, sunitinib malate was indicated for the treatment of GIST after disease progression or intolerance to imatinib me‐ sylate; and, for the treatment of advanced RCC, this based on the partial response rates and duration of responses observed for this drug. On the latest FDA review on sunitinib malate indications, in 2012, it was included the indication for the treatment of progressive, well-dif‐ ferentiated pancreatic neuroendocrine tumors (NET) in patients with unresectable locally

In 2009, FDA approved the multi-kinase inhibitor **pazopanib hydrochloride** targeting VEGFR-1,-2 and -3, PDGFR-α and –β, fibroblast growth factor receptor (FGFR)-1 and -3, c-Kit, interleukin -2 receptor inducible T-cell kinase (Itk), leukocyte-specific protein kinase (Lck), and transmembrane glycoprotein receptor tyrosine kinase (c-Fms). At its first appro‐ val, pazopanib hydrochloride was indicated for the treatment of RCC patients, and at its lat‐ est label review, in 2012, it was also indicated for the treatment of patients with advanced soft tissue sarcoma (STS) who have received prior chemotherapy, except for patients with adipocytic STS or GIST, for which pazopanib hydrochloride's efficacy has not been proved. During the year of 2011, two KIs with different targets and indications have been approved by FDA. Firstly, **vandetanib** a KI with multiple targets, including VEGFR and EGFR, has been approved for the treatment of symptomatic or progressive medullary thyroid cancer (MTC) in patients with unresectable locally advanced or metastatic disease. Also, **crizotinib** was approved for the treatment of patients with anaplasic lymphoma kinase (ALK) -positive locally advanced or metastatic NSCLC. There was no indication review for this drug so far.

phase.

chronic phase.

*3.1.6. Multi-kinase inhibitors*

42 Cancer Treatment - Conventional and Innovative Approaches

advanced or metastatic disease.

One of the most promising KI under trial is PKC412/midostaurin. It is a N-Benzoil deriva‐ tive capable of inhibiting classical protein kinase C (PKC) α, β, γ and the calcium-dependent PKCs δ, ε, η, as well as TK pathways [29]. In 2001, Propper and colleagues published a phase I and pharmacokinetics study on this compound [30]. This study engaged 32 subjects with different types of tumor, which were either refractory to conventional therapy or unre‐ sponsive to standard treatment, exposed to seven doses of PKC412/midostaurin (12.5 mg/day – 300 mg/day). From this study it was concluded the PKC412/midostaurin has had as main toxicity nausea/vomiting and fatigue, with significant side effects as diarrhea, ano‐ rexia, and headache. A dose-related suppression on circulating lymphocyte and monocyte number was observed after 28 days of treatment. The overall conclusion of this work was that PKC412/midostaurin at 150mg/day would be well tolerated chronically. Currently, 7 ac‐ tive clinical trials using PKC412/midostaurin as single drug or in combination with others can be assessed at the Clinical Trial Search engine from National Cancer Institute [31], as well as, at the U.S. National Institute of Health clinical trial database [32].

Among studies using PKC412/midostaurin in combination with other drugs, two trials from Novartis (CPKC412A2114 and CPCK412AUS06T) evaluate the combined therapy of PKC412/midostaurin with the epigenetic drugs 5-azacytidine and decitabine, respectively. The first trial has been carried out with refractory or relapsed ALL and MDS patients' under 18 years old; the second has been carried out with newly diagnosed or relapsed AML pa‐ tients over 60 years old. Also from Novartis, a trial (NCT01477606) evaluates PKC412/ midostaurin in several combinations with the epigenetic drug cytarabine and the anthracy‐ cline daunorubicin, or as single agent, for the treatment of AML patients which express the RTK FLT3-ITD. From the Washington University of Medicine, a study (NCT01161550) eval‐ uated the combination of PKC412/midostaurin with either epigenetic drug cladribine or cy‐ tarabine in AML patients. Furthermore, PKC412/midostaurin has been evaluated on a collaborative trial (NCT01174888) from Novartis and Millennium Pharmaceuticals, Inc. in combination with bortezomib (a proteasome inhibitor), mitoxantrone hydrochloride (an an‐ thracenedione), etoposide (a topoisomerase inhibitor) or cytarabine (an epigenetic drug) for the treatment of patients with relapsed or refractory AML. Finally, PKC412/midostaurin has been tested in combination with radiation therapy and 5-fluorouracil for the treatment of patients with advanced rectal cancer in a study (NCT01282502) sponsored by the Massachu‐ setts General Hospital. As a single agent, PKC412/midostaurin has been tested by Novartis (NCT00866281) for the treatment of relapsed or refractory pediatric patients with AML and ALL. Of interest, by the time this chapter was written, all the above mentioned trials were recruiting participants.

is believed that inhibition of one single isoform can lead to activation of another as a com‐

Target Cancer Therapy

45

http://dx.doi.org/10.5772/55284

As previously mentioned, Raf inhibitors have shown good results on clinical trials. Among these, dabrafenib has been tested as sigle agent or in combination for the treatment of cancer patients, mainly with melanoma. Also, a phase III randomized trial has recently been com‐ pleted, however the early results have not been relieased by the time this chapter was con‐ cluded [43]. Moreover, RAF-265 is currently under phase I and II clinical trials with malignant melanoma patients. This compound is a potent inhibitor of Raf with a highly se‐ lective profile and inhibits all 3 isoforms of RAF, as well as mutant BRAF, with high potency [44]. Additionaly, XL281, a specific inhibitor of RAF kinases, including the mutant form of

Although MEK mutations are rare in human cancer, MEK inhibitors have been developed as a therapeutic strategy to combat B-RAF inhibitor resistance by targeting downstream effec‐ tors. To date, these MEK inhibitors have shown poor efficacy and activity in the clinic. How‐ ever, with the emergence of resistance to B-RAF therapy, and a higher than previously thought frequency of somatic MEK mutations, these inhibitors are finding renewed clinical

Several MEK inhibitors have been identified and are ubdergoing clinical trials: i.e. PD184352 (CI-1040), selumetinib (AZD6244, ARRY-142886), PD0325901, GDC-0973/XL518, trametinib (GSK1120212), MEK162 (ARRY-438162). Worth noticing, most of the known MEK inhibitors are noncompetitive (ie, they do not bind to the ATP–binding site of the kinase) [14]. Despite ATP-biding pockets are highly conserved among human kinases [15], structural analysis of demonstrates tha it harbors a unique site adjacent to the ATP binding site [16]. Thus, biding of inhibitos to this unique MEK site explain the high degree of specificity of the MEK inhibi‐

PD184352 is an orally active highly selective and potent chemical inhibitor of MEK1/2 and was the first MEK inhibitor to enter clinical trials. Selumetinib is the second MEK inhibitor to go into clinical trial after the first MEK inhibitor, CI-1040, demonstrated poor clinical effi‐ cacy. Selumetinib is a benzimidazole derivative with reported nanomolar activity against the purified MEK1 enzyme. Through a series of studies using preclinical cell cultures and animal models, it was shown that Selumetinib suppresses the growth of melanoma cells through the induction of cytostasis, but Selumetinib has a limited ability to induce apoptosis

Akt inhibition promotes decreasing cancer cell survival and proliferation by preventing sig‐ nal transduction through its downstream effectors as mTOR. Target Akt is an interesting

tors compared to other kinase inhibitors with competitive activity.

pensatory mechanism [42].

BRAF, and has finished Phase I testing [45].

*3.2.4. Raf inhibitors*

*3.2.5. MEK inhibitors*

or block angiogenesis [17, 18].

*3.2.6. AKT inhibitors*

use [13].

### *3.2.2. The EGFR inhibitor icotinib*

**Icotinib** has been approved by the State Food and Drug Administration from China, in 2011, under the trade name of Conmana (Beta Pharma Inc.), but it was not yet approved by FDA. It is a reversible EGFR KI capable of inhibiting growth of tumor cell overexpressing EGFR, which underwent two phase I studies reported in 2011 [33, 34]. Both studies demon‐ strated that icotinib is safe and well tolerated by NSCLC patients and shows positive clinical anti-tumor activities.

#### *3.2.3. PI3 kinase inhibitors*

PI3K inhibitors target the p110 catalytic subunit of PI3K, and may be divided into two groups, isoform-specific inhibitors or pan-PI3K inhibitors; the latter can inhibit all class IA PI3Ks. In this way, they block the signal transduction through the PI3K/AKT/mTOR path‐ way exerting antiproliferative effects. The first-generation of PI3K inhibitors included wort‐ mannin, an irreversible PI3K inhibitor isolated from *Penicillium wortimannin*, and LY294002, a synthetic and reversible PI3K inhibitor. However there are limiting features for their clini‐ cal use, which involve low selectivity for PI3K isoforms, poor solubility and toxicity in ani‐ mals [35, 36].

Several other PI3K inhibitors have been developed in an attempt to overcome these initial limitations. Firstly, CAL-101 has 14 trials on phase I, II or III registered [37]. From these 11 are active, and evaluate either safety or efficacy of the drug alone or in combination with others, for the treatment of indolent non-Hodgkin lymphoma (NHL), chronic lymphocytic leukemia (CLL), mantle cell lymphoma (MCL), follicular lymphoma, small lymphocytic lymphoma (SLL), Hodgkin lymphoma, AML, among others. On the other hand, AMG 319 has only one phase I trial registered on the same data base. This trial is currently recruiting patients with hematologic malignancies. Moreover, XL147 has been on nine clinical trials which evaluate its safety and efficacy, alone or in combination, for the treatment of lympho‐ ma, as well as, several solid tumors such as BC, NSCLC and ovarian cancer (OVCA), among others. Furthermore, GDC-0941 has been on 12 clinical trial, nine of which active. From these, a phase I trials evaluate its effect on solid tumors such as BC and NSCLC, as well as in NHL. Two phase II trial are also active, one with NSCLC patients and the other with BC pa‐ tients. Other PI3K inhibitor, BYL719, has been on five active phase I and II trials with pa‐ tients with several solid tumors. Additionally, PX-866 has been on seven pahse I and II trials, five of which active, also for the treatment of solid tumors. Lastly, BKM-120 has been on 43 trials, 42 active, evaluating its effects mostly on solid tumors, such as BC, NSCLC, en‐ dometrial carcinoma and glioblastoma, among others [32, 38, 39]. Compounds specifics for a given isoform can be used at lower doses avoiding side effects. Moreover, these isoformspecific compounds have achieved good results in certain cancers. For instance, a specific p110β inhibitor was shown to be more effective in PTEN-deficient cancer [40], whilst it was suggested that PI3K inhibitor specific for p110α might block angiogenesis [41]. However, it is believed that inhibition of one single isoform can lead to activation of another as a com‐ pensatory mechanism [42].

### *3.2.4. Raf inhibitors*

ALL. Of interest, by the time this chapter was written, all the above mentioned trials were

**Icotinib** has been approved by the State Food and Drug Administration from China, in 2011, under the trade name of Conmana (Beta Pharma Inc.), but it was not yet approved by FDA. It is a reversible EGFR KI capable of inhibiting growth of tumor cell overexpressing EGFR, which underwent two phase I studies reported in 2011 [33, 34]. Both studies demon‐ strated that icotinib is safe and well tolerated by NSCLC patients and shows positive clinical

PI3K inhibitors target the p110 catalytic subunit of PI3K, and may be divided into two groups, isoform-specific inhibitors or pan-PI3K inhibitors; the latter can inhibit all class IA PI3Ks. In this way, they block the signal transduction through the PI3K/AKT/mTOR path‐ way exerting antiproliferative effects. The first-generation of PI3K inhibitors included wort‐ mannin, an irreversible PI3K inhibitor isolated from *Penicillium wortimannin*, and LY294002, a synthetic and reversible PI3K inhibitor. However there are limiting features for their clini‐ cal use, which involve low selectivity for PI3K isoforms, poor solubility and toxicity in ani‐

Several other PI3K inhibitors have been developed in an attempt to overcome these initial limitations. Firstly, CAL-101 has 14 trials on phase I, II or III registered [37]. From these 11 are active, and evaluate either safety or efficacy of the drug alone or in combination with others, for the treatment of indolent non-Hodgkin lymphoma (NHL), chronic lymphocytic leukemia (CLL), mantle cell lymphoma (MCL), follicular lymphoma, small lymphocytic lymphoma (SLL), Hodgkin lymphoma, AML, among others. On the other hand, AMG 319 has only one phase I trial registered on the same data base. This trial is currently recruiting patients with hematologic malignancies. Moreover, XL147 has been on nine clinical trials which evaluate its safety and efficacy, alone or in combination, for the treatment of lympho‐ ma, as well as, several solid tumors such as BC, NSCLC and ovarian cancer (OVCA), among others. Furthermore, GDC-0941 has been on 12 clinical trial, nine of which active. From these, a phase I trials evaluate its effect on solid tumors such as BC and NSCLC, as well as in NHL. Two phase II trial are also active, one with NSCLC patients and the other with BC pa‐ tients. Other PI3K inhibitor, BYL719, has been on five active phase I and II trials with pa‐ tients with several solid tumors. Additionally, PX-866 has been on seven pahse I and II trials, five of which active, also for the treatment of solid tumors. Lastly, BKM-120 has been on 43 trials, 42 active, evaluating its effects mostly on solid tumors, such as BC, NSCLC, en‐ dometrial carcinoma and glioblastoma, among others [32, 38, 39]. Compounds specifics for a given isoform can be used at lower doses avoiding side effects. Moreover, these isoformspecific compounds have achieved good results in certain cancers. For instance, a specific p110β inhibitor was shown to be more effective in PTEN-deficient cancer [40], whilst it was suggested that PI3K inhibitor specific for p110α might block angiogenesis [41]. However, it

recruiting participants.

anti-tumor activities.

mals [35, 36].

*3.2.3. PI3 kinase inhibitors*

*3.2.2. The EGFR inhibitor icotinib*

44 Cancer Treatment - Conventional and Innovative Approaches

As previously mentioned, Raf inhibitors have shown good results on clinical trials. Among these, dabrafenib has been tested as sigle agent or in combination for the treatment of cancer patients, mainly with melanoma. Also, a phase III randomized trial has recently been com‐ pleted, however the early results have not been relieased by the time this chapter was con‐ cluded [43]. Moreover, RAF-265 is currently under phase I and II clinical trials with malignant melanoma patients. This compound is a potent inhibitor of Raf with a highly se‐ lective profile and inhibits all 3 isoforms of RAF, as well as mutant BRAF, with high potency [44]. Additionaly, XL281, a specific inhibitor of RAF kinases, including the mutant form of BRAF, and has finished Phase I testing [45].

### *3.2.5. MEK inhibitors*

Although MEK mutations are rare in human cancer, MEK inhibitors have been developed as a therapeutic strategy to combat B-RAF inhibitor resistance by targeting downstream effec‐ tors. To date, these MEK inhibitors have shown poor efficacy and activity in the clinic. How‐ ever, with the emergence of resistance to B-RAF therapy, and a higher than previously thought frequency of somatic MEK mutations, these inhibitors are finding renewed clinical use [13].

Several MEK inhibitors have been identified and are ubdergoing clinical trials: i.e. PD184352 (CI-1040), selumetinib (AZD6244, ARRY-142886), PD0325901, GDC-0973/XL518, trametinib (GSK1120212), MEK162 (ARRY-438162). Worth noticing, most of the known MEK inhibitors are noncompetitive (ie, they do not bind to the ATP–binding site of the kinase) [14]. Despite ATP-biding pockets are highly conserved among human kinases [15], structural analysis of demonstrates tha it harbors a unique site adjacent to the ATP binding site [16]. Thus, biding of inhibitos to this unique MEK site explain the high degree of specificity of the MEK inhibi‐ tors compared to other kinase inhibitors with competitive activity.

PD184352 is an orally active highly selective and potent chemical inhibitor of MEK1/2 and was the first MEK inhibitor to enter clinical trials. Selumetinib is the second MEK inhibitor to go into clinical trial after the first MEK inhibitor, CI-1040, demonstrated poor clinical effi‐ cacy. Selumetinib is a benzimidazole derivative with reported nanomolar activity against the purified MEK1 enzyme. Through a series of studies using preclinical cell cultures and animal models, it was shown that Selumetinib suppresses the growth of melanoma cells through the induction of cytostasis, but Selumetinib has a limited ability to induce apoptosis or block angiogenesis [17, 18].

#### *3.2.6. AKT inhibitors*

Akt inhibition promotes decreasing cancer cell survival and proliferation by preventing sig‐ nal transduction through its downstream effectors as mTOR. Target Akt is an interesting pharmacological approach due to the Akt activation in consequence of the feedback loop re‐ lease when mTOR is inhibited. Within this group, we can mention allosteric Akt inhibitors (mK2206), Akt catalytic sites inhibitors (PX316, GSK690693, AT-13148, A-443654) and lipidbased phosphatidylinositol (perifosine, triciribine) [32, 36, 39].

sented overall good tolerability [8]. Their potent antitumor effect can be explained by the in‐ hibition of AKT phosphorylation at two sites, S473 and T308, blocking downstream signaling more efficiently than rapamycin/rapalogs and TORinhibs alone, as demonstrated

Target Cancer Therapy

47

http://dx.doi.org/10.5772/55284

Due to its ability to regulate gene transcription, histone acetylation has been increasely stud‐ ied. Histone deacetylases (HDACs) are a group of enzymes that, in conjunction with histone acetyltransferases (HATs), regulate the acetylation status of histone tails. HATs acetylate ly‐ sine residues on histone tails resulting in neutralization of their charge and decreased affini‐

There are 18 HDACs, which are classified according to functional and phylogenetic criteria [49]. They are divided into Zn2+-dependent (class I, II and IV), Zn2+-independent and NADdependent (classIII) enzymes. Most inhibitors currently under development as anti-cancer

There are numerous studies demonstrating that HDACs and HATs also regulate acetylation of nonhistone proteins, including transcription factors, chaperone proteins, and signaling molecules involved in cancer development and progression, such as the tumor suppressor p53 [51]. Furthermore, these enzymes are often overexpressed in various types of cancers, compared with the corresponding normal tissues, and their overexpression is correlated with a poor prognosis [52], because they can drive the silencing of tumor suppressor genes

Over recent years, it has been found that the epigenetic silencing of tumor suppressor genes induced by overexpression of HDACs plays an important role in carcinogenesis, above all in hematological cancers [54]. Thus, HDAC inhibitors (HDACi) have emerged as promising ac‐ cessory therapeutic agents for multiple human malignancies, as, through their action, tumor suppressor gene expression can be restore, cell differentiation can be induce, and both in‐ trinsic and extrinsic apoptotic pathways can be activated [55]. Also, by targeting HDAC6, for example, these inhibitors can stimulate cell cycle arrest, autophagy, and anti-angiogenic effects, can induce oxidative injury, and interfere with tubulin assembly, and cause disrup‐

Several HDACi derived both from natural or synthetic sources have been identified. These compounds share a common pharmacophore containing a cap, a connecting unit, a linker and a zinc binding group that chelates the cation in the catalytic domain of the target HDAC [56]. Thus, this class of inhibitors can be separated into several structurally distinct classes according to their chemical structure [53, 57], and each agent varies in its ability to inhibit

in preclinical studies of NVPBEZ-235 and PI-103 [3, 22, 47].

**4. Epigenetic drugs**

ty for DNA [48].

**4.1. Histona deacetylace inhibitors**

agents target class I, II and IV enzymes [50].

or activation of oncogenes [53].

tion of the aggregosome pathways [50].

individual HDACs.

The allosteric Akt inhibitors act preventing the translocation of Akt to the plasma mem‐ brane, a crucial step for the activation of this molecule, and are more specific for one Akt isoform than the Akt catalytic sites inhibitors which can target all AKT isoforms [42]. Perifo‐ sine, the best-characterized Akt inhibitor, is a lipid-based antitumor agent that inhibits Akt Pleckstrin homology (PH) domain preventing the Akt recruitment to the cell membrane and its activation. Perifosine has shown great efficacy in vitro and in vivo against several human cancers such as breast, ovarian, multiple myeloma and glioma and has been tested in clinical trials [30, 32].

### *3.2.7. mTOR inhibitors*

The ATP-competitive inhibitors of mTOR (TORKinhibs) directly inhibit the mTOR kinase activity affecting both mTORC1 and mTORC2. Thus, resulting in antiproliferative effects by decreasing protein synthesis, inducing cell cycle arrest, and inhibiting angiogenesis in sever‐ al cancer cell lines [22]. Many TORKinhibs have been developed, including Torin1, Torin2, PP242, PP30, KU0063794, WAY-600, WYE-687, WYE-354, XL-388, INK-128, AZD-2014, AZD8055 and OSI-027. Some of them are currently being tested in human subjects with hematological malignancies, glioma and advanced solid tumors in phase I trials [3, 21, 32].

TORKinhibs have achieved better results than rapamycin and rapalogs. This is due to the additional inhibition of mTORC2, which prevents Akt phosphorylation at S473, and also can inhibit mTORC1 with a higher potency. It has been postulated that complete inhibition of mTORC1 is responsible for this enhanced response to treatment, overcoming the limitations of rapamycin. However, it has been found that loss of feedback on PI3K results in activation of downstream effectors other than Akt. Furthermore, these drugs induce phosphorylation of Akt at residue T308, mediated by PDK-1, configuring a resistance mechanism that re‐ quires a different therapeutic approach [18, 22, 46].

### *3.2.8. PI3K and mTOR dual inhibitors*

A strategy to overcome the limitations of rapalogs and TORKinhibs is to target two mole‐ cules in the PI3K/Akt/mTOR pathway, PI3K and mTOR. The dual PI3K/mTOR inhibitors in‐ clude NVP-BEZ235, BGT226, XL765, SF1126, GDC-0980, PI-103, PF-04691502, PKI-587, and SK2126458. These drugs inhibit the catalytic activity of mTOR, targeting both mTORC1 and mTORC2 like the TORKinhibs, beyond that they also inhibit PI3K catalytic subunit. Thus, they act on two fronts in the PI3K/AKT/mTOR signaling pathway decreasing cell prolifera‐ tion, angiogenesis, apoptosis, and inducing cell cycle arrest [21, 47].

The dual PI3K/mTOR inhibitors have demonstrated a greater antitumor efficacy than rapa‐ mycin but also have increased toxicity. Nevertheless, some of them are in phase I/II clinical trials for the treatment of lymphoma, glioma, advanced and refractory solid tumors and pre‐ sented overall good tolerability [8]. Their potent antitumor effect can be explained by the in‐ hibition of AKT phosphorylation at two sites, S473 and T308, blocking downstream signaling more efficiently than rapamycin/rapalogs and TORinhibs alone, as demonstrated in preclinical studies of NVPBEZ-235 and PI-103 [3, 22, 47].

### **4. Epigenetic drugs**

pharmacological approach due to the Akt activation in consequence of the feedback loop re‐ lease when mTOR is inhibited. Within this group, we can mention allosteric Akt inhibitors (mK2206), Akt catalytic sites inhibitors (PX316, GSK690693, AT-13148, A-443654) and lipid-

The allosteric Akt inhibitors act preventing the translocation of Akt to the plasma mem‐ brane, a crucial step for the activation of this molecule, and are more specific for one Akt isoform than the Akt catalytic sites inhibitors which can target all AKT isoforms [42]. Perifo‐ sine, the best-characterized Akt inhibitor, is a lipid-based antitumor agent that inhibits Akt Pleckstrin homology (PH) domain preventing the Akt recruitment to the cell membrane and its activation. Perifosine has shown great efficacy in vitro and in vivo against several human cancers such as breast, ovarian, multiple myeloma and glioma and has been tested in clinical

The ATP-competitive inhibitors of mTOR (TORKinhibs) directly inhibit the mTOR kinase activity affecting both mTORC1 and mTORC2. Thus, resulting in antiproliferative effects by decreasing protein synthesis, inducing cell cycle arrest, and inhibiting angiogenesis in sever‐ al cancer cell lines [22]. Many TORKinhibs have been developed, including Torin1, Torin2, PP242, PP30, KU0063794, WAY-600, WYE-687, WYE-354, XL-388, INK-128, AZD-2014, AZD8055 and OSI-027. Some of them are currently being tested in human subjects with hematological malignancies, glioma and advanced solid tumors in phase I trials [3, 21, 32].

TORKinhibs have achieved better results than rapamycin and rapalogs. This is due to the additional inhibition of mTORC2, which prevents Akt phosphorylation at S473, and also can inhibit mTORC1 with a higher potency. It has been postulated that complete inhibition of mTORC1 is responsible for this enhanced response to treatment, overcoming the limitations of rapamycin. However, it has been found that loss of feedback on PI3K results in activation of downstream effectors other than Akt. Furthermore, these drugs induce phosphorylation of Akt at residue T308, mediated by PDK-1, configuring a resistance mechanism that re‐

A strategy to overcome the limitations of rapalogs and TORKinhibs is to target two mole‐ cules in the PI3K/Akt/mTOR pathway, PI3K and mTOR. The dual PI3K/mTOR inhibitors in‐ clude NVP-BEZ235, BGT226, XL765, SF1126, GDC-0980, PI-103, PF-04691502, PKI-587, and SK2126458. These drugs inhibit the catalytic activity of mTOR, targeting both mTORC1 and mTORC2 like the TORKinhibs, beyond that they also inhibit PI3K catalytic subunit. Thus, they act on two fronts in the PI3K/AKT/mTOR signaling pathway decreasing cell prolifera‐

The dual PI3K/mTOR inhibitors have demonstrated a greater antitumor efficacy than rapa‐ mycin but also have increased toxicity. Nevertheless, some of them are in phase I/II clinical trials for the treatment of lymphoma, glioma, advanced and refractory solid tumors and pre‐

based phosphatidylinositol (perifosine, triciribine) [32, 36, 39].

46 Cancer Treatment - Conventional and Innovative Approaches

quires a different therapeutic approach [18, 22, 46].

tion, angiogenesis, apoptosis, and inducing cell cycle arrest [21, 47].

*3.2.8. PI3K and mTOR dual inhibitors*

trials [30, 32].

*3.2.7. mTOR inhibitors*

### **4.1. Histona deacetylace inhibitors**

Due to its ability to regulate gene transcription, histone acetylation has been increasely stud‐ ied. Histone deacetylases (HDACs) are a group of enzymes that, in conjunction with histone acetyltransferases (HATs), regulate the acetylation status of histone tails. HATs acetylate ly‐ sine residues on histone tails resulting in neutralization of their charge and decreased affini‐ ty for DNA [48].

There are 18 HDACs, which are classified according to functional and phylogenetic criteria [49]. They are divided into Zn2+-dependent (class I, II and IV), Zn2+-independent and NADdependent (classIII) enzymes. Most inhibitors currently under development as anti-cancer agents target class I, II and IV enzymes [50].

There are numerous studies demonstrating that HDACs and HATs also regulate acetylation of nonhistone proteins, including transcription factors, chaperone proteins, and signaling molecules involved in cancer development and progression, such as the tumor suppressor p53 [51]. Furthermore, these enzymes are often overexpressed in various types of cancers, compared with the corresponding normal tissues, and their overexpression is correlated with a poor prognosis [52], because they can drive the silencing of tumor suppressor genes or activation of oncogenes [53].

Over recent years, it has been found that the epigenetic silencing of tumor suppressor genes induced by overexpression of HDACs plays an important role in carcinogenesis, above all in hematological cancers [54]. Thus, HDAC inhibitors (HDACi) have emerged as promising ac‐ cessory therapeutic agents for multiple human malignancies, as, through their action, tumor suppressor gene expression can be restore, cell differentiation can be induce, and both in‐ trinsic and extrinsic apoptotic pathways can be activated [55]. Also, by targeting HDAC6, for example, these inhibitors can stimulate cell cycle arrest, autophagy, and anti-angiogenic effects, can induce oxidative injury, and interfere with tubulin assembly, and cause disrup‐ tion of the aggregosome pathways [50].

Several HDACi derived both from natural or synthetic sources have been identified. These compounds share a common pharmacophore containing a cap, a connecting unit, a linker and a zinc binding group that chelates the cation in the catalytic domain of the target HDAC [56]. Thus, this class of inhibitors can be separated into several structurally distinct classes according to their chemical structure [53, 57], and each agent varies in its ability to inhibit individual HDACs.

Regarding short chain fatty acids class, **valproate** (valproic acid, VPA) has been used as an anticonvulsant for three decades, and has only recently been recognized as an HDAC inhibi‐ tor. It specifically targets 2 of the 4 classes of HDACs: class I, subclasses Ia and Ib, and class II, subclass IIa. Within subclass IIa, HDAC9 is an exception to this modulation, being acti‐ vated by VPA, which is also true for HDAC11 [58]. **Butyrate**, also a short chain fatty acid, naturally produced by bacterial fermentation in the colon, has been designated as the most potent fatty acid in arresting cell proliferation [59].

include thrombocytopenia, neutropenia, diarrhea, nausea, vomiting and fatigue. Extensive studies have been performed to determine whether HDAC inhibitors are associated with cardiac toxicities. Until now, there is little conclusive evidence to determine whether some

Target Cancer Therapy

49

http://dx.doi.org/10.5772/55284

Mechanisms of resistance to HDACi are not well elucidated; however it's believed that it may reflect drug efflux, epigenetic alterations, stress response mechanisms and anti-apop‐ totic, and pro-survival mechanisms [71]. In this context, it is known that DNA hyper-meth‐ ylation may cause resistance to HDACi, inducing compact nucleosomes, blocking the access

HDACi have revealed promise in the clinic but there is clearly space for improvement of therapeutic index. One way to achieve greater clinical efficacy is to use HDACi in combina‐ tion with other chemotherapeutic agents [53, 72]. There have been numerous preclinical and clinical studies examining rational combinations of HDACi with many current therapies for the treatment of hematological and solid malignancies [60]. Indeed, it has been described that HDACi have synergistic or additive effect with different anticancer agents, including

Regarding HDACi in combination with radiotherapy, these inhibitors, including vorinostat, TSA, valproic acid and PCI-24781, enhance the radiosensitivity of cancer cells [73]. Chemo‐ therapeutic agents with additive or synergistic effects with HDACi therapy includes: antitu‐ bulin agent (docetaxel) [74]; topoisomerase II inhibitors (doxorubicin, etoposide, and

HDACi combinations with hormonal therapy are also possible. In this context, clinical trials are in progress for BC and prostate cancer (PC). As a monotherapy, the HDACi vorinostat has not shown effectiveness in metastatic BC and PC [78]. On the other hand, preclinical studies have demonstrated that HDACi potentiates the antitumor activity of tamoxifen in a variety of ER-positive BC cell lines [79]; whereas in PC the addition of an HDACi to the anti‐ androgen bicalutamide have resulted in a synergistic increase in cytotoxicity on hormone-

Recent studies showed that the combination of some of the specific RTK-targeted therapies with HDCAi can represent a novel way for suppressing tumor growth. Combined therapies with transtuzumab [81], erlotinib and gefitinib [82], sorafenib [83], everolimus [84], imatinib [85], heat shock protein-90 inhibitor 17-N-allylamino-17-demethoxygeldanamycin [86] and bortezomide, a proteasome inhibitor [87], have been studied. The obtained data indicate that, although preclinical studies demonstrated a benefit, it is too early to know whether this combination will prove more beneficial than treatment with RTK pathway inhibitors alone. Hematological malignancies appear to be particularly sensitive to HDACi therapy. There are well over 100 clinical trials ongoing with HDACi as monotherapy or in combination therapy for several carcinomas. The available results for these clinical trials have recently been reviewed [50]. As mentioned, vorinostat and romidepsin have been approved by FDA

or all HDAC inhibitors cause electrocardiac changes [70].

to acetylases, which leads to tumor suppression genes silencing [49].

**4.2. Rational combination of HDAC inhibitors with current cancer therapy**

radiation therapy, chemotherapy, hormonal therapies and new targeted agents.

ellipticine) [75, 76]; and DNA cross-linking reagent (i.e. cisplatin) [77].

sensitive and resistant preclinical models [80].

Another class of these inhibitors includes hydroxamic acids. In this group, **vorinostat** (SA‐ HA) and **panobinostat** (LBH 589) are the most extensively studied drugs. The latter is cur‐ rently under phase II/III clinical trials, and the former has been approved by FDA for the treatment of relapsed and refractory cutaneous T-cell lymphoma [60]. Vorinostat represents the second generation of the polar-planar compounds and is a relatively selective inhibitor for class I HDACs; that is, by inhibiting HDAC-1, −2, −3 and −8, but also with mild activity against class II HDAC-6, −10 and −11 [61]. However, vorinostat lacks activity against class II HDAC-4, −5, −7 and −8. **Belinostat**, other compound of this group, has shown efficacy as monotherapy, and has been the basis for the first pivotal phase I trial of this agent to treat relapsed or refractory peripheral T-cell lymphoma [62]. Belinostat's anticancer effect is thought to be mediated through multiple mechanisms of action, including the inhibition of cell proliferation, induction of apoptosis, inhibition of angiogenesis, and induction of differ‐ entiation [63]. Moreover, it has been demonstrated that **resminostat** inhibits proliferation and induces apoptosis in multiple myeloma cells [64]. HDACi **PCI-24781** has been shown to enhance chemotherapy-induced apoptosis in multidrug- resistant sarcoma cell lines [65]. **Gi‐ vinostat** is currently being tested on three trials, but none of these on neoplasias [32], and **JNJ-26481585** shows results in blood malignancies in phase I trial as monotherapy and in combination with proteasome inhibitor (bortezomib).

On benzamides, **entinostat** (MS-275) is an isotype-selective synthetic benzamide derivative HDACi with predominant class I inhibition. Entinostat has been investigated in patients with advanced refractory acute leukemias, mainly acute myeloid leukemia [66]. Whereas, **mocetinostat** is well-tolerated and exhibits favorable pharmacokinetic and pharmacody‐ namic profiles indicating target inhibition and clinical responses. It induces cell death and autophagy, synergizes with proteasomal inhibitors and affects non-histone targets, such as microtubules [67]. Yet, mocetinostat shows selectivity for HDAC I/II. It has been used in clinical trials mostly for hematological malignancies, such as AML, CML, NHL and refracto‐ ry Hodgkin disease, where it has shown very encouraging results [68].

Regarding cyclic tetrapeptides, **romidepsin** (ISTODAX®) shows potential as a new agent, having revealed remarkable activity in the treatment of T-cell lymphomas in preclinical studies and early-phase clinical trials. In 2006, it was approved by FDA for the treatment of CTCL in patients who have received at least one prior systemic therapy [69].

Preclinical studies in cell lines and animal models, HDACi have been proven to be very suc‐ cessful as single-modality agents for the treatment of a variety of cancers. Thus, several structurally different HDACi have been used in numerous clinical trials to test their toxicity and effectiveness [32]. The most common adverse effects associated with HDAC inhibitors include thrombocytopenia, neutropenia, diarrhea, nausea, vomiting and fatigue. Extensive studies have been performed to determine whether HDAC inhibitors are associated with cardiac toxicities. Until now, there is little conclusive evidence to determine whether some or all HDAC inhibitors cause electrocardiac changes [70].

Mechanisms of resistance to HDACi are not well elucidated; however it's believed that it may reflect drug efflux, epigenetic alterations, stress response mechanisms and anti-apop‐ totic, and pro-survival mechanisms [71]. In this context, it is known that DNA hyper-meth‐ ylation may cause resistance to HDACi, inducing compact nucleosomes, blocking the access to acetylases, which leads to tumor suppression genes silencing [49].

### **4.2. Rational combination of HDAC inhibitors with current cancer therapy**

Regarding short chain fatty acids class, **valproate** (valproic acid, VPA) has been used as an anticonvulsant for three decades, and has only recently been recognized as an HDAC inhibi‐ tor. It specifically targets 2 of the 4 classes of HDACs: class I, subclasses Ia and Ib, and class II, subclass IIa. Within subclass IIa, HDAC9 is an exception to this modulation, being acti‐ vated by VPA, which is also true for HDAC11 [58]. **Butyrate**, also a short chain fatty acid, naturally produced by bacterial fermentation in the colon, has been designated as the most

Another class of these inhibitors includes hydroxamic acids. In this group, **vorinostat** (SA‐ HA) and **panobinostat** (LBH 589) are the most extensively studied drugs. The latter is cur‐ rently under phase II/III clinical trials, and the former has been approved by FDA for the treatment of relapsed and refractory cutaneous T-cell lymphoma [60]. Vorinostat represents the second generation of the polar-planar compounds and is a relatively selective inhibitor for class I HDACs; that is, by inhibiting HDAC-1, −2, −3 and −8, but also with mild activity against class II HDAC-6, −10 and −11 [61]. However, vorinostat lacks activity against class II HDAC-4, −5, −7 and −8. **Belinostat**, other compound of this group, has shown efficacy as monotherapy, and has been the basis for the first pivotal phase I trial of this agent to treat relapsed or refractory peripheral T-cell lymphoma [62]. Belinostat's anticancer effect is thought to be mediated through multiple mechanisms of action, including the inhibition of cell proliferation, induction of apoptosis, inhibition of angiogenesis, and induction of differ‐ entiation [63]. Moreover, it has been demonstrated that **resminostat** inhibits proliferation and induces apoptosis in multiple myeloma cells [64]. HDACi **PCI-24781** has been shown to enhance chemotherapy-induced apoptosis in multidrug- resistant sarcoma cell lines [65]. **Gi‐ vinostat** is currently being tested on three trials, but none of these on neoplasias [32], and **JNJ-26481585** shows results in blood malignancies in phase I trial as monotherapy and in

On benzamides, **entinostat** (MS-275) is an isotype-selective synthetic benzamide derivative HDACi with predominant class I inhibition. Entinostat has been investigated in patients with advanced refractory acute leukemias, mainly acute myeloid leukemia [66]. Whereas, **mocetinostat** is well-tolerated and exhibits favorable pharmacokinetic and pharmacody‐ namic profiles indicating target inhibition and clinical responses. It induces cell death and autophagy, synergizes with proteasomal inhibitors and affects non-histone targets, such as microtubules [67]. Yet, mocetinostat shows selectivity for HDAC I/II. It has been used in clinical trials mostly for hematological malignancies, such as AML, CML, NHL and refracto‐

Regarding cyclic tetrapeptides, **romidepsin** (ISTODAX®) shows potential as a new agent, having revealed remarkable activity in the treatment of T-cell lymphomas in preclinical studies and early-phase clinical trials. In 2006, it was approved by FDA for the treatment of

Preclinical studies in cell lines and animal models, HDACi have been proven to be very suc‐ cessful as single-modality agents for the treatment of a variety of cancers. Thus, several structurally different HDACi have been used in numerous clinical trials to test their toxicity and effectiveness [32]. The most common adverse effects associated with HDAC inhibitors

potent fatty acid in arresting cell proliferation [59].

48 Cancer Treatment - Conventional and Innovative Approaches

combination with proteasome inhibitor (bortezomib).

ry Hodgkin disease, where it has shown very encouraging results [68].

CTCL in patients who have received at least one prior systemic therapy [69].

HDACi have revealed promise in the clinic but there is clearly space for improvement of therapeutic index. One way to achieve greater clinical efficacy is to use HDACi in combina‐ tion with other chemotherapeutic agents [53, 72]. There have been numerous preclinical and clinical studies examining rational combinations of HDACi with many current therapies for the treatment of hematological and solid malignancies [60]. Indeed, it has been described that HDACi have synergistic or additive effect with different anticancer agents, including radiation therapy, chemotherapy, hormonal therapies and new targeted agents.

Regarding HDACi in combination with radiotherapy, these inhibitors, including vorinostat, TSA, valproic acid and PCI-24781, enhance the radiosensitivity of cancer cells [73]. Chemo‐ therapeutic agents with additive or synergistic effects with HDACi therapy includes: antitu‐ bulin agent (docetaxel) [74]; topoisomerase II inhibitors (doxorubicin, etoposide, and ellipticine) [75, 76]; and DNA cross-linking reagent (i.e. cisplatin) [77].

HDACi combinations with hormonal therapy are also possible. In this context, clinical trials are in progress for BC and prostate cancer (PC). As a monotherapy, the HDACi vorinostat has not shown effectiveness in metastatic BC and PC [78]. On the other hand, preclinical studies have demonstrated that HDACi potentiates the antitumor activity of tamoxifen in a variety of ER-positive BC cell lines [79]; whereas in PC the addition of an HDACi to the anti‐ androgen bicalutamide have resulted in a synergistic increase in cytotoxicity on hormonesensitive and resistant preclinical models [80].

Recent studies showed that the combination of some of the specific RTK-targeted therapies with HDCAi can represent a novel way for suppressing tumor growth. Combined therapies with transtuzumab [81], erlotinib and gefitinib [82], sorafenib [83], everolimus [84], imatinib [85], heat shock protein-90 inhibitor 17-N-allylamino-17-demethoxygeldanamycin [86] and bortezomide, a proteasome inhibitor [87], have been studied. The obtained data indicate that, although preclinical studies demonstrated a benefit, it is too early to know whether this combination will prove more beneficial than treatment with RTK pathway inhibitors alone.

Hematological malignancies appear to be particularly sensitive to HDACi therapy. There are well over 100 clinical trials ongoing with HDACi as monotherapy or in combination therapy for several carcinomas. The available results for these clinical trials have recently been reviewed [50]. As mentioned, vorinostat and romidepsin have been approved by FDA for the treatment advanced and refractory cutaneous T-cell lymphoma (CTCL). The clinical value of HDACi in other malignancies remains to be determined.

identified, molecular factors may influence the *in vivo* anti-tumor effectiveness of this class

Some PARP inhibitors, targeting both PARP-1 and PARP-2, were recently under clinical de‐ velopment, which include Pfizer's PF 01367338 (AG014699), AstraZeneca's olaparib (AZD2281, KU-0059436), Sanofi-Aventis' iniparib (BSI 201) and Abbott Laboratories' veli‐

The first agent analyzed clinically was AG014699 (the phosphate salt of AG14361), in 2003. Publications described preclinical data for 39 OVCA cell lines (without reporting BRCA sta‐ tus of these cell lines) with AG014699 as single-agent or in combination (with carboplatin, doxorubicin, gemcitabine, paclitaxel, or topotecan) using combination index/isobologram analysis for multiple drug effect analysis. The investigators noted a concentration-depend‐ ent efficacy across the different cell lines to different degrees. The greatest impact appears to be in combination with carboplatin, topotecan, and doxorubicin. Therefore, an initial phase I was conducted with temozolide (TMZ), both given for 5 days in 28-day cycles, with patients with solid tumors. A subsequent phase II study with melanoma patients has been reported. Overall, there was modest activity with significant myelosuppression. The study started us‐

hibitory dose (PID) as evaluated from peripheral blood mononuclear cell (PBMCs). The PID, defined as at least 50% of decrease in PARP activity 24 hours after dosing, was determined

clear cells (PBMCs) PARP. The mean terminal half-life was 7.4-11.7 hours. The PARP in the PBMCs recovered at least 50% function by 72 hours after dosing. The dose limiting toxicity (DLT) for the highest dose level tested of 18 mg/m2 in combination with standard dose TMZ and lead to myelosuppression [110]. The phase II study evaluated the efficacy of AG014699 at 12 mg/m2 with TMZ at 200 mg/m2 in 40 chemotherapy-naive patients with advanced mul‐ tiple melanoma. Myelosuppression was more significant in the phase II trial than seen in the phase I trial. It was reported several signs of toxicity besides fatigue and nausea: 12% grade four thrombocytopenia, 15% neutropenia, and one death from febrile neutropenia. There were four partial responses (PRs), four prolonged stable diseases, and 10 patients were too

Olaparib is an oral PARP inhibitor (IC50 = 4.9 nM for PARP 1) extensively studied for BRCA tumors treatment in combination or as single agent. In a phase I trial, olaparib was given at days 1-4, cisplatin at day 3, and gemcitabine at days 3 and 10, every 21 days. As toxicities effects, five of six patients experienced grade three or four thrombocytopenia. Two PRs were reported in 1 pancreatic cancer and 1 NSCLC patient [112]. Another phase I, this time focus‐ ing olaparib as single-agent, enrolled 60 patients with solid tumors, including 22 BRCA mu‐ tation patients. This study supported the synthetic lethality concept. Patients were treated at escalating doses and duration. Doses of 10 mg QD 2 out of 3 weeks to 600 mg BID continu‐ ously were evaluated. The initial cohort was not restricted to BRCA-deficient patients but was enriched for this population. In the expansion cohort, patients had to have BRCA muta‐

and at this dose there was 74-97% inhibition of peripheral blood mononu‐

) of TMZ and AG014699 was escalated to PARP in‐

Target Cancer Therapy

51

http://dx.doi.org/10.5772/55284

of drugs [107, 108].

parib (ABT 888) [109].

to be 12 mg/m2

**5.2. PARPs inhibitors under clinical development**

ing one-half standard dose (100 mg/m2

early to evaluate at the time of the report [111].

### **5. PARPs inhibitors**

Poly ADP ribose polymerases (PARPs) are a family of 17 proteins pooled together based on their structural similarity, specifically, they are composed by two ribose moieties and two phosphates per polymer unit [88]. Known since 1963, these enzymes function is to catalyses the polymerization and formation of highly negatively charged poly ADP ribose chains on target proteins, therefore modifying their action [89]. Furthermore, PARPs contain three zinc finger motifs which bind with high affinity to DNA breaks and triggers the enzyme's cata‐ lytic module and synthesis of negatively-charged, branched polymers of poly(ADP-ribose) (PAR) from NAD+ [90]. Currently, PARP 1 and PARP 2 are the best understood of these proteins and their key role is to maintain genomic integrity, in particular the repair of single strand DNA lesions and breaks, using the base excision repair (BER) pathway [91]. More‐ over, PARPs are also involved in activating apoptosis on both caspase dependent or inde‐ pendent fashion; however this PARP hole is not yet fully understood and will not be discussed in this chapter [92].

#### **5.1. PARPs inhibitors in cancer therapy**

Durkacz and colleagues proposed, in 1980, that modulating PARP-1 might augment the ef‐ fect of alkylating chemotherapy [93]. So far the modulation of its activity by stimulation or inhibition can be applied in therapy or prevention of several pathologies including cardiac infarct [94], septic shock [95], diabetes [96], inflammation [97], neurodegenerative disorders [98], and acute necrotizing pancreatitis [99]. Lately a new potential strategy for therapy has emerged, the PARP inhibitors, using the synthetic lethality and exploiting tumor-specific ge‐ netic alterations. Synthetic lethality is defined as the premise, whereby, deletion of one of two genes independently has no effect on cellular viability, whereas, simultaneous loss of both genes is lethal [100]. It has become clear that the genomic instability of some tumor cells allows PARP inhibitors to have selectivity for the tumor cells over normal cells, what explains why this class of drugs shows fewer side effects as a single agent. Taken together, inhibition of these enzymes and, therefore, the BER pathway causes persistence of single strand breaks (SSBs) leading to cell death. Also, PARP inhibitors, when in combination with cytotoxic agents, prevent repair of SSBs caused by these agents in cells with underlying ho‐ mologous recombination (HR) defects [101].

It has been shown that cancer cells with mutations in the breast and ovarian susceptibility genes BRCA1 and BRCA2 are extremely sensitive to small molecule inhibitors of PARP-1 [102, 103]. Thus, PARP inhibitors have raised as a promise in phase I and phase II clinical trials for the treatment of BRCA1/2-deficient breast, ovarian and prostate tumors [104-106]. However, a recently completed phase III study combining PARP inhibition with chemother‐ apy did not generate the anticipated survival gains; suggesting that additional, as yet un‐ identified, molecular factors may influence the *in vivo* anti-tumor effectiveness of this class of drugs [107, 108].

### **5.2. PARPs inhibitors under clinical development**

for the treatment advanced and refractory cutaneous T-cell lymphoma (CTCL). The clinical

Poly ADP ribose polymerases (PARPs) are a family of 17 proteins pooled together based on their structural similarity, specifically, they are composed by two ribose moieties and two phosphates per polymer unit [88]. Known since 1963, these enzymes function is to catalyses the polymerization and formation of highly negatively charged poly ADP ribose chains on target proteins, therefore modifying their action [89]. Furthermore, PARPs contain three zinc finger motifs which bind with high affinity to DNA breaks and triggers the enzyme's cata‐ lytic module and synthesis of negatively-charged, branched polymers of poly(ADP-ribose) (PAR) from NAD+ [90]. Currently, PARP 1 and PARP 2 are the best understood of these proteins and their key role is to maintain genomic integrity, in particular the repair of single strand DNA lesions and breaks, using the base excision repair (BER) pathway [91]. More‐ over, PARPs are also involved in activating apoptosis on both caspase dependent or inde‐ pendent fashion; however this PARP hole is not yet fully understood and will not be

Durkacz and colleagues proposed, in 1980, that modulating PARP-1 might augment the ef‐ fect of alkylating chemotherapy [93]. So far the modulation of its activity by stimulation or inhibition can be applied in therapy or prevention of several pathologies including cardiac infarct [94], septic shock [95], diabetes [96], inflammation [97], neurodegenerative disorders [98], and acute necrotizing pancreatitis [99]. Lately a new potential strategy for therapy has emerged, the PARP inhibitors, using the synthetic lethality and exploiting tumor-specific ge‐ netic alterations. Synthetic lethality is defined as the premise, whereby, deletion of one of two genes independently has no effect on cellular viability, whereas, simultaneous loss of both genes is lethal [100]. It has become clear that the genomic instability of some tumor cells allows PARP inhibitors to have selectivity for the tumor cells over normal cells, what explains why this class of drugs shows fewer side effects as a single agent. Taken together, inhibition of these enzymes and, therefore, the BER pathway causes persistence of single strand breaks (SSBs) leading to cell death. Also, PARP inhibitors, when in combination with cytotoxic agents, prevent repair of SSBs caused by these agents in cells with underlying ho‐

It has been shown that cancer cells with mutations in the breast and ovarian susceptibility genes BRCA1 and BRCA2 are extremely sensitive to small molecule inhibitors of PARP-1 [102, 103]. Thus, PARP inhibitors have raised as a promise in phase I and phase II clinical trials for the treatment of BRCA1/2-deficient breast, ovarian and prostate tumors [104-106]. However, a recently completed phase III study combining PARP inhibition with chemother‐ apy did not generate the anticipated survival gains; suggesting that additional, as yet un‐

value of HDACi in other malignancies remains to be determined.

50 Cancer Treatment - Conventional and Innovative Approaches

**5. PARPs inhibitors**

discussed in this chapter [92].

**5.1. PARPs inhibitors in cancer therapy**

mologous recombination (HR) defects [101].

Some PARP inhibitors, targeting both PARP-1 and PARP-2, were recently under clinical de‐ velopment, which include Pfizer's PF 01367338 (AG014699), AstraZeneca's olaparib (AZD2281, KU-0059436), Sanofi-Aventis' iniparib (BSI 201) and Abbott Laboratories' veli‐ parib (ABT 888) [109].

The first agent analyzed clinically was AG014699 (the phosphate salt of AG14361), in 2003. Publications described preclinical data for 39 OVCA cell lines (without reporting BRCA sta‐ tus of these cell lines) with AG014699 as single-agent or in combination (with carboplatin, doxorubicin, gemcitabine, paclitaxel, or topotecan) using combination index/isobologram analysis for multiple drug effect analysis. The investigators noted a concentration-depend‐ ent efficacy across the different cell lines to different degrees. The greatest impact appears to be in combination with carboplatin, topotecan, and doxorubicin. Therefore, an initial phase I was conducted with temozolide (TMZ), both given for 5 days in 28-day cycles, with patients with solid tumors. A subsequent phase II study with melanoma patients has been reported. Overall, there was modest activity with significant myelosuppression. The study started us‐ ing one-half standard dose (100 mg/m2 ) of TMZ and AG014699 was escalated to PARP in‐ hibitory dose (PID) as evaluated from peripheral blood mononuclear cell (PBMCs). The PID, defined as at least 50% of decrease in PARP activity 24 hours after dosing, was determined to be 12 mg/m2 and at this dose there was 74-97% inhibition of peripheral blood mononu‐ clear cells (PBMCs) PARP. The mean terminal half-life was 7.4-11.7 hours. The PARP in the PBMCs recovered at least 50% function by 72 hours after dosing. The dose limiting toxicity (DLT) for the highest dose level tested of 18 mg/m2 in combination with standard dose TMZ and lead to myelosuppression [110]. The phase II study evaluated the efficacy of AG014699 at 12 mg/m2 with TMZ at 200 mg/m2 in 40 chemotherapy-naive patients with advanced mul‐ tiple melanoma. Myelosuppression was more significant in the phase II trial than seen in the phase I trial. It was reported several signs of toxicity besides fatigue and nausea: 12% grade four thrombocytopenia, 15% neutropenia, and one death from febrile neutropenia. There were four partial responses (PRs), four prolonged stable diseases, and 10 patients were too early to evaluate at the time of the report [111].

Olaparib is an oral PARP inhibitor (IC50 = 4.9 nM for PARP 1) extensively studied for BRCA tumors treatment in combination or as single agent. In a phase I trial, olaparib was given at days 1-4, cisplatin at day 3, and gemcitabine at days 3 and 10, every 21 days. As toxicities effects, five of six patients experienced grade three or four thrombocytopenia. Two PRs were reported in 1 pancreatic cancer and 1 NSCLC patient [112]. Another phase I, this time focus‐ ing olaparib as single-agent, enrolled 60 patients with solid tumors, including 22 BRCA mu‐ tation patients. This study supported the synthetic lethality concept. Patients were treated at escalating doses and duration. Doses of 10 mg QD 2 out of 3 weeks to 600 mg BID continu‐ ously were evaluated. The initial cohort was not restricted to BRCA-deficient patients but was enriched for this population. In the expansion cohort, patients had to have BRCA muta‐ tion to enroll and were treated at 200 mg BID continuously. Eight PRs, by response evalua‐ tion criteria in solid tumors (RECIST), were observed out of the 15 patients with BRCA mutation-related advanced OVCA group. All the responses in OVCA were seen in BRCA mutated tumors [105].

cules can be targeted at once, in combination or not with conventional therapies, issues associated to resistance are thought to be milder than with chemotherapy alone. Altogether, we consider that target therapy brings the possibility of increasing patients' overall survival,

Target Cancer Therapy

53

http://dx.doi.org/10.5772/55284

Taciane Ladislau, Klesia P Madeira, Renata D Daltoé, Isabella S Guimarães, Sarah F Teixeira,

Laboratory of Cellular and Molecular Biology of Human Cancer, Federal University of Es‐

Authors Taciane Ladislau and Klesia P Madeira equally contributed to the elaboration of

[1] Blume-jensen, P, & Hunter, T. Oncogenic kinase signaling. Nature (2001). , 411,

[2] Dancey, J, & Sausville, E. A. Issues and progress with protein kinase inhibitors for

[3] Willems, L, Tamburini, J, Chapuis, N, & Lacombe, C. Mayeux P & Bouscary D. PI3K and mTOR signaling pathways in cancer: new data on targeted therapies. Current

[4] Ogita S & LoRuss PTargeting phosphatidylinositol 3 kinase (PI3K)-Akt beyond rapa‐

[5] Roberts, P. J. Der CJ. Targeting the Raf-MEK-ERK mitogen-activated protein kinase

[6] Zhang, J, Yang, P. L, & Gray, N. S. Targeting cancer with small molecule kinase in‐

[7] Adnane, L, Trail, P. A, Taylor, I, & Wilhelm, S. M. Sorafenib (BAY 43-9006, Nexavar), a dual-action inhibitor that targets RAF/MEK/ERK pathway in tumor cells and tyro‐ sine kinases VEGFR/PDGFR in tumor vasculature. Methods in Ezymology (2006). ,

cascade for the treatment of cancer. Oncogene (2007). , 26(22), 3291-310.

cancer treatment. Nature Reviews Drug Discovery (2003). , 2(4), 296-313.

quality of life, and, maybe, could point to the possibility of vanquishing this disease.

Paulo CM Lyra-Júnior, Iuri C Valadão, Leticia BA Rangel and Alice L Herlinger

**Author details**

pírito Santo State, Brazil

this chapter

**References**

355-365.

407, 597-612.

Oncology Reports (2012). , 14, 129-138.

logs. Targeted Oncology (2011). , 6, 103-117.

hibitors. Nature Reviews Cancer (2009). , 9(1), 28-39.

Iniparib (BSI 201 or 4-iodo-3-nitrobenzamide) is a prodrug which irreversibly inhibits PARP-1 and it is the first PARP inhibitor to show survival advantage in triple-negative breast cancer (TNBC) patients. It has entered in phase III study despite the fact its active me‐ tabolite is still unknown. Iniparib is given intravenously twice a week. The phase I study in‐ cluded 23 patients with solid tumors. The concentration that brought about efficacy in preclinical models was 20-30 ng/mL, so achievable levels were well over the preclinical effi‐ cacious levels. The 2.8 mg/kg dose caused PARP inhibition in PBMCs by more than 50% with the first dose. Subsequent dosing increased the amount of PARP inhibition to more than 80%. Six of the 23 heavily pretreated patients had stable disease for at least 2 months (up to over 9 months in 1 patient) [113].

Veliparib has been shown to be a potent inhibitor of PARP, as well as, to have a good bioa‐ vailability. In pre-clinical studies veliparib potentiated TMZ, platinum agents, cyclophos‐ phamide, and radiation in syngeneic and xenograft tumor models [114]. Combined with topotecan, veliparib has showed significant myelosuppression. The original schedule was topotecan at days 8 and 2-5 at 1.2 mg/m2 , and veliparib 10 mg BID at days 1-7. The schedule was changed to topotecan at days 1-5 when 0.9 mg/m2 of it was not tolerated [115]. Further‐ more, PARP inhibitors also augmented the effect of irradiation *in vivo,* as shown in mouse colon cancer xenograft model, where combined therapy increased survival from 23 days with radiation alone to 36 days. One subject also presented complete remission (CR) [108].

Unfortunately, as well as for other therapies, resistance to PARP inhibitors has already been reported. A possible explanation for that would be that a second mutation, a compensatory mutation or a crossover could reestablish the wild-type BCRA protein, reversing the BCRA deficiency [109]. Additionally, upregulation of p-glycoprotein efflux pump, 53BP1 silencing 53BP1 and increased expression of PARP by the tumor have also been shown as a resistance mechanism for PARP inhibitors [116]. Nevertheless, overcoming this resistance could be achieved by: a third mutation on BCRA, which converts the cell back to the mutated form; a mutation that inhibits HR; downregulation of the P-glycoprotein pump; or, upregulation of 53BP1. Recently 6-thioguanine (6-TG) has been shown to be active in cells resistant to PARP inhibitors in BRCA2 deficient tumors [117].

### **6. Conclusions**

Despite the difficulties encountered by physicians and patients in the fight against cancer, we are currently witnessing an ever growing spectrum of new targets and strategies to com‐ bat this disease. Considering that an optimal therapy for cancer would be developed based on specific aspect of each patient, target therapies appear as important alternatives to over‐ come the hurdles presented by currently available strategies. Moreover, as different mole‐ cules can be targeted at once, in combination or not with conventional therapies, issues associated to resistance are thought to be milder than with chemotherapy alone. Altogether, we consider that target therapy brings the possibility of increasing patients' overall survival, quality of life, and, maybe, could point to the possibility of vanquishing this disease.

### **Author details**

tion to enroll and were treated at 200 mg BID continuously. Eight PRs, by response evalua‐ tion criteria in solid tumors (RECIST), were observed out of the 15 patients with BRCA mutation-related advanced OVCA group. All the responses in OVCA were seen in BRCA

Iniparib (BSI 201 or 4-iodo-3-nitrobenzamide) is a prodrug which irreversibly inhibits PARP-1 and it is the first PARP inhibitor to show survival advantage in triple-negative breast cancer (TNBC) patients. It has entered in phase III study despite the fact its active me‐ tabolite is still unknown. Iniparib is given intravenously twice a week. The phase I study in‐ cluded 23 patients with solid tumors. The concentration that brought about efficacy in preclinical models was 20-30 ng/mL, so achievable levels were well over the preclinical effi‐ cacious levels. The 2.8 mg/kg dose caused PARP inhibition in PBMCs by more than 50% with the first dose. Subsequent dosing increased the amount of PARP inhibition to more than 80%. Six of the 23 heavily pretreated patients had stable disease for at least 2 months

Veliparib has been shown to be a potent inhibitor of PARP, as well as, to have a good bioa‐ vailability. In pre-clinical studies veliparib potentiated TMZ, platinum agents, cyclophos‐ phamide, and radiation in syngeneic and xenograft tumor models [114]. Combined with topotecan, veliparib has showed significant myelosuppression. The original schedule was

was changed to topotecan at days 1-5 when 0.9 mg/m2 of it was not tolerated [115]. Further‐ more, PARP inhibitors also augmented the effect of irradiation *in vivo,* as shown in mouse colon cancer xenograft model, where combined therapy increased survival from 23 days with radiation alone to 36 days. One subject also presented complete remission (CR) [108]. Unfortunately, as well as for other therapies, resistance to PARP inhibitors has already been reported. A possible explanation for that would be that a second mutation, a compensatory mutation or a crossover could reestablish the wild-type BCRA protein, reversing the BCRA deficiency [109]. Additionally, upregulation of p-glycoprotein efflux pump, 53BP1 silencing 53BP1 and increased expression of PARP by the tumor have also been shown as a resistance mechanism for PARP inhibitors [116]. Nevertheless, overcoming this resistance could be achieved by: a third mutation on BCRA, which converts the cell back to the mutated form; a mutation that inhibits HR; downregulation of the P-glycoprotein pump; or, upregulation of 53BP1. Recently 6-thioguanine (6-TG) has been shown to be active in cells resistant to PARP

Despite the difficulties encountered by physicians and patients in the fight against cancer, we are currently witnessing an ever growing spectrum of new targets and strategies to com‐ bat this disease. Considering that an optimal therapy for cancer would be developed based on specific aspect of each patient, target therapies appear as important alternatives to over‐ come the hurdles presented by currently available strategies. Moreover, as different mole‐

, and veliparib 10 mg BID at days 1-7. The schedule

mutated tumors [105].

(up to over 9 months in 1 patient) [113].

52 Cancer Treatment - Conventional and Innovative Approaches

topotecan at days 8 and 2-5 at 1.2 mg/m2

inhibitors in BRCA2 deficient tumors [117].

**6. Conclusions**

Taciane Ladislau, Klesia P Madeira, Renata D Daltoé, Isabella S Guimarães, Sarah F Teixeira, Paulo CM Lyra-Júnior, Iuri C Valadão, Leticia BA Rangel and Alice L Herlinger

Laboratory of Cellular and Molecular Biology of Human Cancer, Federal University of Es‐ pírito Santo State, Brazil

Authors Taciane Ladislau and Klesia P Madeira equally contributed to the elaboration of this chapter

### **References**


[8] Egberts, F, Kahler, K. C, Livingstone, E, & Hauschild, A. Metastaticmelanoma: Scien‐ tific rationale for sorafenib treatment and clinical results. Onkologie (2008). , 3, 398-403.

potential for combination in preclinical models. Molecular Cancer Therapeutics

Target Cancer Therapy

55

http://dx.doi.org/10.5772/55284

[19] Liu, Q, Thoreen, C, & Wang, J. Sabatini D & Gray NS. mTOR mediated anti-cancer drug discovery. Drug Discovery Today: Therapeutic Strategies (2009). , 6, 47-55.

[20] Alvarado, Y, Mita, M. M, & Vemulapalli, S. Mahalingam D & Mita AC. Clinical activ‐ ity of mammalian target of rapamycin inhibitors in solid tumors. Targeted Oncology

[21] Zaytseva, Y. Y, & Valentino, J. D. Gulhati P & Evers BM. mTOR inhibitors in cancer

[22] Guertin DA & Sabatini DMThe Pharmacology of mTOR Inhibition. Science Signaling

[23] Sarbassov, D. D, Ali, S. M, Sengupta, S, Sheen, J. H, Hsu, P. P, Bagley, A. F, Mar‐ khard, A. L, & Sabatini, D. M. Prolonged rapamycin treatment inhibits mTORC2 as‐

[24] Zeng, Z. Sarbassov dos D, Samudio IJ, Yee KW, Munsell MF, Ellen Jackson C, Giles FJ, Sabatini DM, Andreeff M & Konopleva M. Rapamycin derivatives reduce mTORC2 signaling and inhibit AKT activation in AML. Blood (2007). , 109,

[25] Guertin DA & Sabatini DMDefining the role of mTOR in cancer. Cancer Cell (2007). ,

[26] Food, U. S. and Drug Administration. FDA: Drugs. http://www.fda.gov/Drugs/

[27] Diaz-padilla, I, & Duran, I. Clarke BA & Oza AM. Biologic rationale and clinical ac‐ tivity of mTOR inhibitors in gynecological cancer. Cancer Treatment Reviews

[28] Weisberg, E, Manley, P, Mestan, J, Cowan-jacob, S, Ray, A, & Griffin, J. D. AMN107 (nilotinib): a novel and selective inhibitor of BCR-ABL. British Journal of Cancer

[29] Propper, D. J, Mcdonald, A. C, Man, A, Thavasu, P, Balkwill, F, Braybrooke, J. P, Ca‐ ponigro, F, Graf, P, Dutreix, C, Blackie, R, Kaye, S. B, Ganesan, T. S, Talbot, D. C, Harris, A. L, Twelves, C, & Phase, I. and pharmacokinetic study of PKC412, an inhib‐

[30] Sun W & Modak SEmerging treatment options for the treatment of neuroblastoma: potential role of perifosine. Journal of Onco Targets and Therapy (2012). , 5, 21-29.

[31] National Cancer InstituteNCI: Search for Clinical Trials. http://www.cancer.gov/clini‐

itor of protein kinase C. Journal of Clinical Oncology (2001). , 19(5), 1485-92.

(2007). , 6(8), 2209-2219.

(2011). , 6, 69-94.

(2009). , 2, 24-30.

3509-3512.

12, 9-22.

(2012). , 38, 767-775.

(2006). , 94(12), 1765-1769.

therapy. Cancer Letters (2012). , 319, 1-7.

default.htmaccessed 7 August (2012).

caltrials/searchaccessed 6 August (2012).

sembly and Akt/PKB. Molecular Cell (2006). , 22, 159-168.


potential for combination in preclinical models. Molecular Cancer Therapeutics (2007). , 6(8), 2209-2219.

[19] Liu, Q, Thoreen, C, & Wang, J. Sabatini D & Gray NS. mTOR mediated anti-cancer drug discovery. Drug Discovery Today: Therapeutic Strategies (2009). , 6, 47-55.

[8] Egberts, F, Kahler, K. C, Livingstone, E, & Hauschild, A. Metastaticmelanoma: Scien‐ tific rationale for sorafenib treatment and clinical results. Onkologie (2008). , 3,

[9] Eisen, T, Ahmad, T, Flaherty, K. T, Gore, M, Kaye, S, Marais, R, Gibbens, I, Hackett, S, James, M, Schuchter, L. M, Nathanson, K. L, Xia, C, Simantov, R, Schwartz, B, Pou‐ lin-costello, M, Dwyer, O, & Ratain, P. J. MJ. Sorafenib in advanced melanoma: A phase II randomised discontinuation trial analysis. British Journal of Cancer (2006). ,

[10] Gupta-abramson, V, Troxel, A. B, Nellore, A, Puttaswamy, K, Redlinger, M, Ransone, K, Mandel, S. J, Flaherty, K. T, Loevner, L. A, Dwyer, O, Brose, P. J, & Phase, M. S. II Trial of sorafenib in advanced thyroid cancer. Journal of Clinical Oncology (2008). ,

[11] Keating, G. M. Vemurafenib: in unresectable or metastatic melanoma. BioDrugs

[12] Gollob, J. A, Wilhelm, S, Carter, C, & Kelley, S. L. Role of Raf kinase in cancer: thera‐ peutic potential of targeting the Raf/MEK/ERK signal transduction pathway. Semi‐

[13] Bromberg-white, J. L, Andersen, N. J, & Duesbery, N. S. MEK genomics in develop‐ ment and disease. Briefings in Functional Genomics (2012). , 11(4), 300-310.

[14] Wallace, E. M, Lyssikatos, J. P, Yeh, T, Winkler, J. D, & Koch, K. Progress towards therapeutic small molecule MEK inhibitors for use in cancer therapy. Current Topics

[15] Messersmith, W. A, Hidalgo, M, Carducci, M, & Eckhardt, S. G. Novel targets in sol‐ id tumors: MEK inhibitors. Clinical Advances in Hematology and Oncology (2006). ,

[16] Ohren, J. F, Chen, H, Pavlovsky, A, Whitehead, C, Zhang, E, Kuffa, P, Yan, C, Mccon‐ nell, P, Spessard, C, Banotai, C, Mueller, W. T, Delaney, A, Omer, C, Sebolt-leopold, J, Dudley, D. T, Leung, I. K, Flamme, C, Warmus, J, Kaufman, M, Barrett, S, Tecle, H, & Hasemann, C. A. Structures of human MAP kinase kinase 1 (MEK1) and MEK2 de‐ scribe novel noncompetitive kinase inhibition. Nature Structural & Molecular Biolo‐

[17] Allen, L. F, Sebolt-leopold, J, & Meyer, M. B. CI-1040 (PD184352), a target signal transduction inhibitor of MEK (MAPKK). Seminars in Oncology (2003). , 30(5),

[18] Davies, B. R, Logie, A, Mckay, J. S, Martin, P, Steele, S, Jenkins, R, Cockerill, M, Car‐ tlidge, S, & Smith, P. D. AZD6244 (ARRY-142886), a potent inhibitor of mitogen-acti‐ vated protein kinase/extracellular signal-regulated kinase kinase 1/2 kinases: mechanism of action in vivo, pharmacokinetic/pharmacodynamic relationship, and

398-403.

54 Cancer Treatment - Conventional and Innovative Approaches

95(5), 581-586.

26(29), 4714-4719.

4(11), 831-836.

105-116.

gy (2004). , 11(12), 1192-1197.

(2012). , 26(5), 325-324.

nars in Oncology (2006). , 33(4), 392-406.

in Medicinal Chemistry (2005). , 5(2), 215-229.


[32] U.S. National Institute of Health clinicaltrials.gov. http://clinicaltrials.gov/ct2/search (accessed 7 August 2012).

[44] James, J, Ruggeri, B, Armstrong, R. C, Rowbottom, M. W, Jones-bolin, S, Gunawar‐ dane, R. N, Dobrzanski, P, Gardner, M. F, Zhao, H, Cramer, M. D, Hunter, K, Nepo‐ muceno, R. R, Cheng, M, Gitnick, D, Yazdanian, M, Insko, D. E, Ator, M. A, Apuy, J. L, Faraoni, R, Dorsey, B. D, Williams, M, Bhagwat, S. S, & Holladay, M. W. CEP-32496: a novel orally active BRAF(inhibitor with selective cellular and in vivo

Target Cancer Therapy

57

http://dx.doi.org/10.5772/55284

[45] Beeram, M, Patnaik, A, & Rowinsky, E. K. Raf: a strategic target for therapeutic de‐ velopment agains cancer. Journal of Clinical Oncology (2005). , 23(27), 6771-6790. [46] Thoreen, C. C, Kang, S. A, Chang, J. W, Liu, Q, Zhang, J, Gao, Y, Reichling, L. J, Sim, T, Sabatini, D. M, & Gray, N. S. An ATP-competitive mammalian target of rapamycin inhibitor reveals rapamycin-resistant functions of mTORC1. The Journal of Biological

[47] Manara, M. C, Nicoletti, G, Zambelli, D, Ventura, S, Guerzoni, C, Landuzzi, L, Lolli‐ ni, P. L, Maira, S. M, García-echeverría, C, & Mercuri, M. Picci P & Scotlandi K. NVP-BEZ235 as a new therapeutic option for sarcomas. Clinical Cancer Research (2010). ,

[48] Hong, L, Schroth, G. P, Matthews, H. R, Yau, P, & Bradbury, E. M. Studies of the DNA binding properties of histone H4 amino terminus. Thermal denaturation stud‐ ies reveal that acetylation markedly reduces the binding constant of the H4 "tail" to

[49] Marks, P. A, & Xu, W. S. Histone deacetylase inhibitors: Potential in cancer therapy.

[50] Khan, O. La Thangue NB. HDAC inhibitors in cancer biology: emerging mechanisms and clinical applications. Immunology and Cell Biology (2012). , 90, 85-94.

[51] Gu, W, & Roeder, R. G. Activation of sequence-specific DNA binding by acetylation

[52] Weichert, W, Röske, A, Gekeler, V, Beckers, T, Stephan, C, Jung, K, Fritzsche, F. R, Niesporek, S, Denkert, C, Dietel, M, & Kristiansen, G. Histone deacetylases 1, 2 and 3 are highly expressed in prostate cancer and HDAC2 expression is associated with shorter PSA relapse time after radical prostatectomy. British Journal of Cancer

[53] Miller, C. P, & Singh, M. M. Rivera-Del Valle N, Manton CA, Chandra J. Therapeutic strategies to enhance the anticancer efficacy of histone deacetylase inhibitors. Journal

[54] Pan, L. N, Lu, J, & Huang, B. HDAC inhibitors: a potential new category of anti-tu‐

mor agents. Cellular & Molecular Immunology (2007). , 4, 337-343.

antitumor activity. Molecular Cancer Therapie (2012). , 600E

Chemistry (2009). , 284, 8023-32.

DNA. Blood (1993). , 268, 305-314.

(2008). , 98, 604-610.

Journal of Cellular Biochemistry (2009). , 107, 600-608.

of Biomedicine and Biotechnology (2011). , 2011, 1-17.

of the p53 C-terminal domain. Cell (1997). , 53.

16, 530-40.


[44] James, J, Ruggeri, B, Armstrong, R. C, Rowbottom, M. W, Jones-bolin, S, Gunawar‐ dane, R. N, Dobrzanski, P, Gardner, M. F, Zhao, H, Cramer, M. D, Hunter, K, Nepo‐ muceno, R. R, Cheng, M, Gitnick, D, Yazdanian, M, Insko, D. E, Ator, M. A, Apuy, J. L, Faraoni, R, Dorsey, B. D, Williams, M, Bhagwat, S. S, & Holladay, M. W. CEP-32496: a novel orally active BRAF(inhibitor with selective cellular and in vivo antitumor activity. Molecular Cancer Therapie (2012). , 600E

[32] U.S. National Institute of Health clinicaltrials.gov. http://clinicaltrials.gov/ct2/search

[33] Wang, H. P, Zhang, L, Wang, Y. X, Tan, F. L, Xia, Y, Ren, G. J, Hu, P, Jiang, J, Wang, M. Z, & Xiao, Y. Phase I trial of icotinib, a novel epidermal growth factor receptor tyrosine kinase inhibitor, in Chinese patients with non-small cell lung cancer. Chi‐

[34] Zhao, Q, Shentu, J, Xu, N, Zhou, J, Yang, G, Yao, Y, Tan, F, Liu, D, Wang, Y, & Zhou, J. Phase I study of icotinib hydrochloride (BPI-2009H), an oral EGFR tyrosine kinase inhibitor, in patients with advanced NSCLC and other solid tumors. Lung Cancer

[35] LoPiccolo JBlumenthal GM, Bernstein WB & Dennis PA. Targeting the PI3K/Akt/ mTOR pathway: effective combinations and clinical considerations. Drug Resistance

[36] Liu, P, & Cheng, H. Roberts TM & Zhao JJ. Targeting the phosphoinositide 3-kinase (PI3K) pathway in cancer. Nature Reviews Drug Discovery (2009). , 8, 627-644.

[37] Mccubrey, J. A, Steelman, L. S, Abrams, S. L, Lee, J. T, Chang, F, Bertrand, F. E, Navo‐ lanic, P. M, Terrian, D. M, Franklin, R. A, Assoro, D, Salisbury, A. B, Mazzarino, J. L, Stivala, M. C, & Libra, F. M. Roles of the RAF/MEK/ERK and PI3K/ PTEN/AKT path‐ ways in malignant transformation and drug resistance. Advances in Enzyme Regula‐

[38] Schatz, J. H. Targeting the PI3K/AKT/mTOR pathway in non-Hodgkin's lymphoma: results, biology, and development strategies. Current Oncology Reports (2011). ,

[39] Hernandez-aya, L. F, & Gonzalez-angulo, A. M. Targeting the phosphatidylinositol 3-kinase signaling pathway in breast cancer. The Oncologist (2011). , 16, 404-414. [40] Jia, S, Liu, Z, Zhang, S, Liu, P, Zhang, L, Lee, S. H, Zhang, J, Signoretti, S, & Loda, M. Roberts TM & Zhao JJ. Essential roles of PI(3)K-in cell growth, metabolism and tu‐

[41] Graupera, M, Guillermet-guibert, J, Foukas, L. C, Phng, L. K, Cain, R. J, Salpekar, A, Pearce, W, Meek, S, Millan, J, Cutillas, P. R, Smith, A. J, Ridley, A. J, & Ruhrberg, C. Gerhardt H & Vanhaesebroeck B. Angiogenesis selectively requires the isoform of

[42] Engelman, J. A, & Targeting, P. I. K signalling in cancer: opportunities, challenges

[43] Anforth, R. M, Blumetti, T. C, Kefford, R. F, Sharma, R, Scolyer, R. A, Kossard, S, Long, G. V, & Fernandez-peñas, P. Cutaneous Manifestations of Dabrafenib (GSK2118436): A Selective Inhibitor of Mutant BRAF in patients with Metastatic Mel‐

PI3K to control endothelial cell migration. Nature (2008). , 110alpha.

and limitations. Nature Reviews Cancer (2009). , 9, 550-562.

anoma. British Journal of Dermatology (2012). , 1365-2133.

(accessed 7 August 2012).

56 Cancer Treatment - Conventional and Innovative Approaches

(2011). , 73(2), 195-202.

Updates (2008). , 11, 32-50.

tion (2006). , 46(1), 249-279.

morigenesis. Nature (2008). , 110beta.

13398-406.

nese Medical Journal (English Edition) (2011).


[55] Xu, W, Ngo, L, Perez, G, Dokmanovic, M, & Marks, P. A. Intrinsic apoptotic and thi‐ oredoxin pathways in human prostate cancer cell response to histone deacetylase in‐ hibitor. Proceedings of the National Academy of Sciences (2006). , 103, 15540-15545.

tide reductase inhibitor, in adults with advanced hematologic malignancies. Leuke‐

Target Cancer Therapy

59

http://dx.doi.org/10.5772/55284

[67] Boumber, Y, Younes, A, & Garcia-manero, G. Mocetinostat (MGCD0103): a review of an isotype-specific histone deacetylase inhibitor. Expert Opinion on Investigational

[68] Tambaro, F. P. Dell'aversana C, Carafa V, Nebbioso A, Radic B, Ferrara F, Altucci L. Histone deacetylase inhibitors: clinical implications for hematological malignancies.

[69] Jain, S, & Zain, J. Romidepsin in the treatment of cutaneous T-cell lymphoma. Journal

[70] Münster, P, Marchion, D, Bicaku, E, Schmitt, M, Lee, J. H, Deconti, R, Simon, G, Fish‐ man, M, Minton, S, Garrett, C, Chiappori, A, Lush, R, Sullivan, D, & Daud, A. Phase I trial of histone deacetylase inhibition by valproic acid followed by the topoisomerase II inhibitor epirubicin in advanced solid tumors: a clinical and translational study.

[71] Fantin, V. R, & Richon, V. M. Mechanisms of resistance to histone deacetylase inhibi‐ tors and their therapeutic implications. Clinical Cancer Research (2007). , 13,

[72] Bots, M, & Johnstone, R. W. Rational combinations using HDAC inhibitors. Clinical

[73] Munshi, A, Kurland, J. F, Nishikawa, T, Tanaka, T, Hobbs, M. L, Tucker, S. L, Ismail, S, Stevens, C, & Meyn, R. E. Histone deacetylase inhibitors radiosensitize human melanoma cells by suppressing DNA repair activity. Clinical Cancer Research

[74] Owonikoko, T. K, Ramalingam, S. S, Kanterewicz, B, Balius, T. E, Belani, C. P, & Hershberger, P. A. Vorinostat increases carboplatin and paclitaxel activity in nonsmall-cell lung cancer cells. Internacional Journal of Cancer (2010). , 126, 743-755.

[75] Lopez, G, Liu, J, Ren, W, Wei, W, Wang, S, Lahat, G, Zhu, Q. S, Bornmann, W. G, Mcconkey, D. J, Pollock, R. E, & Lev, D. C. Combining PCI-24781, a novel histone de‐ acetylase inhibitor, with chemotherapy for the treatment of soft tissue sarcoma. Clini‐

[76] Das, C. M, Aguilera, D, Vasquez, H, Prasad, P, Zhang, M, Wolff, J. E, & Gopalak‐ rishnan, V. Valproic acid induces and topoisomerase-II (alpha/beta) expression and synergistically enhances etoposide cytotoxicity in human glioblastoma cell lines.

[77] Noguchi, H, Yamashita, H, Murakami, T, Hirai, K, Noguchi, Y, Maruta, J, Yokoi, T, & Noguchi, S. Successful treatment of anaplastic thyroid carcinoma with a combination

mia Research (2007). , 31, 1165-1173.

Drugs (2011). , 20, 823-829.

Clinical Epigenetics (2010).

7237-7242.

(2005). , 11, 4912-4922.

of Blood Medicine (2011). , 2, 37-47.

Cancer Research (2009). , 15, 3970-3977.

cal Cancer Research (2009). , 15, 3472-3483.

Journal of Neuro-Oncology (2007). , 21.

Journal of Clinical Oncology (2007). , 15, 1979-1985.


tide reductase inhibitor, in adults with advanced hematologic malignancies. Leuke‐ mia Research (2007). , 31, 1165-1173.

[67] Boumber, Y, Younes, A, & Garcia-manero, G. Mocetinostat (MGCD0103): a review of an isotype-specific histone deacetylase inhibitor. Expert Opinion on Investigational Drugs (2011). , 20, 823-829.

[55] Xu, W, Ngo, L, Perez, G, Dokmanovic, M, & Marks, P. A. Intrinsic apoptotic and thi‐ oredoxin pathways in human prostate cancer cell response to histone deacetylase in‐ hibitor. Proceedings of the National Academy of Sciences (2006). , 103, 15540-15545.

[56] Bertrand, P. Inside HDAC with HDAC inhibitors. The European Journal of Medici‐

[57] Dickinson, M, Johnstone, R. W, & Prince, H. M. Histone deacetylase inhibitors: po‐ tential targets responsible for their anti-cancer effect. Investigational New Drugs

[58] Bradbury, C. A, Khanim, F. L, Hayden, R, Bunce, C. M, White, D. A, Drayson, M. T, Craddock, C, & Turner, B. M. Histone deacetylases in acute myeloid leukaemia show a distinctive pattern of expression that changes selectively in response to deacetylase

[59] Louis, M, Rosato, R. R, Brault, L, Osbild, S, Battaglia, E, Yang, X. H, Grant, S, & Ba‐ grel, D. The histone deacetylase inhibitor sodium butyrate induces breast cancer cell apoptosis through diverse cytotoxic actions including glutathione depletion and oxi‐

[60] Thurn, K. T, Thomas, S, Moore, A, & Munster, P. N. Rational therapeutic combina‐ tions with histone deacetylase inhibitors for the treatment of cancer. Future Oncolo‐

[61] Matalon, S, Palmer, B. E, Nold, M. F, Furlan, A, Kassu, A, Fossati, G, Mascagni, P, & Dinarello, C. A. The histone deacetylase inhibitor ITF2357 decreases surface CXCR4 and CCR5 expression on CD4(+) T-cells and monocytes and is superior to valproic acid for latent HIV-1 expression in vitro. Journal of Acquired Immune Deficiency

[62] Zain, J. M, & Connor, O. O. Targeted treatment and new agents in peripheral T-cell

[63] Kapoor, S. Inhibition of HDAC6-dependent carcinogenesis: emerging, new therapeu‐ tic options besides belinostat. International Journal of Cancer (2009). , 124, 509-520.

[64] Mandl-weber, S, Meinel, F. G, Jankowsky, R, Oduncu, F, Schmidmaier, R, & Bau‐ mann, P. The novel inhibitor of histone deacetylase resminostat (RAS2410) inhibits proliferation and induces apoptosis in multiple myeloma (MM) cells. British Journal

[65] Yang, C, Choy, E, Hornicek, F. J, Wood, K. B, Schwab, J. H, Liu, X, Mankin, H, & Duan, Z. Histone deacetylase inhibitor PCI-24781 enhances chemotherapy-induced apoptosis in multidrug-resistant sarcoma cell lines. Anticancer Research (2011). , 31,

[66] Gojo, I, Tidwell, M. L, Greer, J, Takebe, N, Seiter, K, Pochron, M. F, Johnson, B, Sznol, M, Karp, J. E, & Phase, I. and pharmacokinetic study of Triapine, a potent ribonucleo‐

lymphoma. International Journal of Hematology (2010). , 92, 33-44.

dative stress. International Journal of Oncology (2004). , 25, 1701-1711.

nal Chemistry (2010). , 45, 2095-2116.

58 Cancer Treatment - Conventional and Innovative Approaches

inhibitors. Leukemia (2005). , 19, 1751-1759.

(2010). , 28, 3-20.

gy (2011). , 2, 263-283.

Syndromes (2010). , 54, 1-9.

of Haematology (2010). , 149, 218-528.

1115-1123.


of oral valproic acid, chemotherapy, radiation and surgery. Endocrinology Journal (2009). , 56, 245-249.

[87] Yu, C, Rahmani, M, Conrad, D, Subler, M, Dent, P, & Grant, S. The proteasome inhib‐ itor bortezomib interacts synergistically with histone deacetylase inhibitors to induce apoptosis in Bcr/Abl+ cells sensitive and resistant to STI571. Blood (2003). , 102,

Target Cancer Therapy

61

http://dx.doi.org/10.5772/55284

[88] Zaremba, T, & Curtin, N. J. PARP inhibitor development for systemic cancer target‐

[89] Chambon, P, Weill, J. D, & Mandel, P. Nicotinamide mononucleotide activations of new DNA-dependent polyadenylic acid synthesizing nuclear enzyme. Biochemical

[90] Malanga, M, & Althaus, F. R. The role of poly(ADP-ribose) in the DNA damage sig‐

[91] Schreiber, V, Dantzer, F, Ame, J. C, & De Murcia, G. Poly(ADP-ribose): novel func‐ tions for an old molecule. Nature Reviews Molecular Cell Biology (2006). , 7(7),

[92] Sevrioukova, I. F. Apoptosis-inducing factor: structure, function, andredox regula‐

[93] Durkacz, B. W, Omidiji, O, Gray, D. A, & Shall, S. ADP-ribose)n participates in DNA

[94] Roesner, J. P, Mersmann, J, Bergt, S, Bohnenberg, K, Barthuber, C, Szabo, C, Nöldgeschomburg, G. E, & Zacharowsi, K. Therapeutic injection of PARP inhibitor INO-1001 preserves cardiac function in porcine myocardial ischemia and reperfusion

[95] Petrilli, V, Herceg, Z, Hassa, P. O, & Patel, N. S. Di Paola R, Cortes U, Dugo L, Filipe HM, Thiemermann C, Hottiger MO, Cuzzodrea S, Wang ZQ. Noncleavablep‐ oly(ADP-ribose) polymerase-1 regulates the inflammation response in mice. Journal

[96] Drel, V. R, Pacher, P, Stevens, M. J, & Obrosova, I. G. Aldose reductase inhibition counteracts nitrosative stress and poly(ADP-ribose) polymerase activation in diabetic rat kidney and high-glucose-exposed human mesangial cells. Free Radical Biology &

[97] Suzuki, Y, Masini, E, Mazzocca, C, Cuzzocrea, S, Ciampa, A, Suzuki, H, & Bani, D. Inhibition of poly(ADP-ribose) polymerase prevents allergen-induced asthmalike re‐ action in sensitized Guinea pigs. Journal of Pharmacology and Experimental Thera‐

[98] Cosi, C, Suzuki, H, Skaper, S. D, Milani, D, Facci, L, Menegazzi, M, Vantini, G, Kanai, Y, Degryse, A, Colpaert, F, Koek, W, & Marien, M. R. Poly(ADP-ribose) polymerase (PARP) revisited. A new role for na old enzyme: PARP involvement in neurodegen‐

ings. Anti- Cancer Agents in Medicinal Chemistry (2007). , 7(5), 515-523.

and Biophysical Research Communications (1963). , 11, 39-43.

tion. Antioxid.Redox. Signal (2011). , 14, 2545-2579.

excision repair. Nature (1980). , 283(5747), 593-596.

of Clinical Investigation (2004). , 114, 1072-1081.

Medicine (2006). , 40, 1454-1465.

peutics (2004). , 311, 1241-1248.

without reducing infarct size. Shock (2010). , 33, 507-512.

naling network. Biochemistry and Cell Biology (2005). , 83, 354-364.

3765-3774.

517-528.


[87] Yu, C, Rahmani, M, Conrad, D, Subler, M, Dent, P, & Grant, S. The proteasome inhib‐ itor bortezomib interacts synergistically with histone deacetylase inhibitors to induce apoptosis in Bcr/Abl+ cells sensitive and resistant to STI571. Blood (2003). , 102, 3765-3774.

of oral valproic acid, chemotherapy, radiation and surgery. Endocrinology Journal

[78] Luu, T. H, Morgan, R. J, Leong, L, Lim, D, Mcnamara, M, Portnow, J, Frankel, P, Smith, D. D, & Doroshow, J. H. Wong. A phase II trial of vorinostat (suberoylanilide hydroxamic acid) in metastatic breast cancer: a California Cancer Consortium study.

[79] Biçaku, E, Marchion, D. C, Schmitt, M. L, & Münster, P. N. Selective inhibition of his‐ tone deacetylase 2 silences progesterone receptor-mediated signaling. Cancer Re‐

[80] Pfeiffer, M. J, Mulders, P. F, & Schalken, J. A. An in vitro model for preclinical testing of endocrine therapy combinations for prostate cancer. Prostate (2010). , 70,

[81] Conte, P, Campone, M, & Pronzato, P. Phase I trial of panobinostat (LBH589) in com‐ bination with trastuzumab in pretreated HERpositive metastatic breast cancer (MBC): preliminary safety and tolerability results. Journal Clinical Oncology (2009). ,

[82] Witta, S. E, Dziadziuszko, R, Yoshida, K, Hedman, K, & Varella-garcia, M. Bunn PA Jr, Hirsch FR. ErbB-3 expression is associated with E-cadherin and their coexpression restores response to gefitinib in non-small-cell lung cancer (NSCLC). Annals of On‐

[83] Baradari, V, Höpfner, M, Huether, A, Schuppan, D, & Scherübl, H. Histone deacety‐ lase inhibitor MS-275 alone or combined with bortezomib or sorafenib exhibits strong antiproliferative action in human cholangiocarcinoma cells. World Journal of

[84] Wedel, S, Hudak, L, Seibel, J. M, Juengel, E, Tsaur, I, Wiesner, C, Haferkamp, A, & Blaheta, R. A. Inhibitory effects of the HDAC inhibitor valproic acid on prostate can‐ cer growth are enhanced by simultaneous application of the mTOR inhibitor

[85] Nguyen, T, Dai, Y, Attkisson, E, Kramer, L, Jordan, N, Nguyen, N, Kolluri, N, Mu‐ schen, M, & Grant, S. HDAC inhibitors potentiate the activity of the BCR/ABL kinase inhibitor KW-2449 in imatinib-sensitive or-resistant BCR/ABL+ leukemia cells in vi‐

[86] Rahmani, M, Reese, E, Dai, Y, Bauer, C, Kramer, L. B, Huang, M, Jove, R, Dent, P, & Grant, S. Cotreatment with suberanoylanilide hydroxamic acid and 17-allylamino 17 demethoxygeldanamycin synergistically induces apoptosis in Bcr-Abl+ Cells sensi‐ tive and resistant to STI571 (imatinib mesylate) in association with down-regulation of Bcr-Abl, abrogation of signal transducer and activator of transcription 5 activity, and Bax conformational change. Molecular Pharmacology (2005). , 67, 1166-1176.

tro and in vivo. Clinical Cancer Research (2011). , 17, 3219-3232.

(2009). , 56, 245-249.

60 Cancer Treatment - Conventional and Innovative Approaches

search (2008). , 68, 1513-1519.

cology (2009). , 20, 989-695.

Gastroenterology (2007). , 13, 4458-4466.

RAD001. Life Science (2011). , 88, 418-424.

1524-1532.

2.

Clinical Cancer Research (2008). , 14, 7138-7142.


eration and PARP inhibitors as possible neuroprotectiveagentes. Annals of the New York Academy of Sciences (1997). , 825, 366-379.

[109] Hirschhom, R. In vivo reversion to normal of inherited mutation in humans. Journal

Target Cancer Therapy

63

http://dx.doi.org/10.5772/55284

[110] Ihnem, M. Therapeutic advantage of chemotherapy drugs in combination with PARP inhitor PF-01367338 (AG-014699) in human ovarian cancer cells [abstract]. European

[111] Plummer, R. First and final report of a phase II study of the poly(ADP-ribose) poly‐ merase (PARP) inhibitor, AG014699, in combination with temozolomide (TMZ) in patiens with metastatic malignant melanoma (MM). Journal of Clinical Oncology

[112] Rajan, A. A phase I combination study of olaparib (AZD 2208; KU-0059436) and cis‐ platin plus gemcitabine in adults with solid tumors [Abstract]. Target Anticancer

[113] Kopetz, S. First in human phase I study of BSI-201, a small molecule inhibitor of poly ADP-ribose polymerase (PARP) in subjects with advanced solid tumors [ASCO Ab‐

[114] Donawho, C. K, Luo, Y, Penning, T. D, Bauch, J. L, Bouska, J. J, Bontcheva-diaz, V. D, Cox, B. F, Deweese, T. L, Dillehay, L. E, Ferguson, D. C, Ghoreishi-haack, N. S, Grimm, D. R, Guan, R, Han, E. K, Holley-shanks, R. R, Hristov, B, Idler, K. B, Jarvis, K, Johnson, E. F, Kleinberg, L. R, Klinghofer, V, Lasko, L. M, Liu, X, Marsh, K. C, Mcgonigal, T. P, Meulbroek, J. A, Olson, A. M, Palma, J. P, Rodriguez, L. E, Shi, Y, Stavropoulos, J. A, Tsurutani, A. C, Zhu, G. D, Rosenberg, S. H, Giranda, V. L, & Frost, D. J. ABT-888, an orally active poly(ADPribose) polymerase inhibitor that po‐ tentiates DNA-damaging agents in preclinical tumor models. Clinical Cancer Re‐

[115] Kummar, S, Chen, A. P, Zhang, R, Putvana, R. J, Kinders, L, Rubinstein, L, Parch‐ ment, R. E, Tomazewski, J. E, Doroshow, J. H, & Bethesda, M. D. Pharmacodynamic response in phase I combination study of ABT-888 and topotecan in adults with re‐ fractory solid tumors and lymphomas [ASCO Abstract]. Journal of Clinical Oncology

[116] Bunting, S. F, Callen, E, Wong, N, Chen, H. T, Polato, F, Gunn, A, Bothmer, A, Feld‐ hahn, N, Fernandez-capetillo, O, Cao, L, Xu, X, Deng, C. X, Finkel, T, Nussenzweig, M, Stark, J. M, & Nussenzweig, A. BP1 inhibits homologous recombination in BRCA1-deficient cells by blocking resection of DNA breaks. Cell (2010). , 141(2),

[117] Issaeva, N, Thomas, H. D, Djurenovic, T, Jaspers, J. E, Stoimenov, I, Kyle, S, Pedley, N, Gottipati, P, Zur, R, Sleeth, K, Chatzakos, V, Mulligan, E. A, Lundin, C, Gubano‐ va, E, Kerbergen, A, Harris, A. L, Sharma, R. A, Rottenberg, S, Curtin, N. J, & Helle‐ day, T. Thioguanine selectively kills BRAC2-defective tumors and overcomes PARP

inhibitor resistance. Cancer Research (2010). , 70(15), 6268-6276.

of Medical Genetics (2003). , 40(10), 721-728.

stract 3577]. Journal of Clinical Oncology (2008).

(2006). s): ASCO abst8013.

search (2007). , 13(9), 2728-2737.

(2010). s).

243-254.

Therapies (2010).

Organization for Research and Treatment of Cancer (2010).


[109] Hirschhom, R. In vivo reversion to normal of inherited mutation in humans. Journal of Medical Genetics (2003). , 40(10), 721-728.

eration and PARP inhibitors as possible neuroprotectiveagentes. Annals of the New

[99] Yasar, M, Uysal, B, Kaldirim, U, Oztas, Y, Sadir, S, Ozler, M, Topal, T, Coskun, O, Kilic, A, Cayci, T, Poyrazoglu, Y, Oter, S, Korkmaz, A, & Guven, A. Poly(ADP-ribose) polymerase inhibition modulates experimental acute necrotizing pancreatitis in‐ duced oxidative stress, bacterial translocation and neopterin concentrations in rats.

[100] Kaelin, W. G. The concept of synthetic lethality in the context of anticancer therapy.

[101] Satoh, M. S, Poirier, G. G, & Lindahl, T. Dual function for poly(ADP-ribose) synthesis in response to DNA strand breakage. Biochemistry (1994). , 33(23), 7099-7106. [102] Bryant, H. E, Schultz, N, Thomas, H. D, Parker, K. M, Flower, D, Lopez, E, Kyle, S, Meuth, M, Curtin, N. J, & Helleday, T. Specific killing of BRCA2-deficient tumours

with inhibitors of poly(ADP-ribose) polymerase. Nature (2005). , 434, 913-917. [103] Farmer, H, Mccabe, N, & Lord, C. J. Tutt ANJ, Johnson DA, Richardson TB, Santarosa M, Dillon KJ, Hickson I, Knights C., Martin NMB, Jackson SP, Smith GCM, Ashworth A. Targeting the DNA repair defect in BRCA mutant cells as a therapeutic strategy.

[104] Audeh, M. W, Carmichael, J, Penson, R. T, Friedlander, M, & Powell, B. Bell-McGuinn KM, Scott C, Weitzel JN, Oaknin A, Loman N, Lu K, Schmutzler RK, Matu‐ lonis U, Wickens M, Tutt A. Oral poly(ADPribose) polymerase inhibitor olaparib in patiens with BRCA1 or BRCA2 mutations and recurrent ovarian cancer: a proof-of-

[105] Fong, P. C, Boss, D. S, Yap, T. A, Tutt, A. N, Wu, P, Mergui-roelvink, M, Mortimer, P, Swaisland, H, Lau, A, Connor, O, Ashworth, M. J, Carmichael, A, Kaye, J, Schellens, S. B, & De Bono, J. H. JS. Inhibition of poly(ADP-ribose) polymerase in tumors from BRCA mutation carriers. The New England Journal of Medicine (2009). , 361, 123-134.

[106] Tutt, A. N, Robson, M, Garber, J. E, Domchek, S. M, Audeh, M. W, Weitzel, J. N, Friedlander, M, Arun, B, Loman, N, Schmutzler, R. K, Wardley, A, Mitchell, G, Earl, H, Wickens, M, & Carmichael, J. Oral poly(ADPribose) polymerase inhibitor olaparib in patients with BRCA1 or BRCA2 mutations and advanced breast cancer: a proof-of-

[107] Guha, M. PARP inhibitors stumble in breast cancer. Nature Biotechnology (2011). ,

[108] Shaughnessy, O, Osborne, J, Pippen, C, Yoffe, J. E, Patt, M, Rocha, D, Koo, C, Sher‐ man, I. C, & Bradley, B. M. C. Iniparib plus chemotherapy in metastatic triple-nega‐ tive breast cancer. The New England Journal of Medicine (2011). , 364, 205-214.

York Academy of Sciences (1997). , 825, 366-379.

62 Cancer Treatment - Conventional and Innovative Approaches

Nature Reviews Cancer (2005). , 5, 689-698.

Nature (2005). , 434, 917-921.

concept trial. Lancet (2010). , 376, 245-251.

concept trial. Lancet (2010). , 376, 235-244.

29, 373-374.

Experimental Biology and Medicine (2010). , 235, 1126-1133.


**Chapter 3**

and K+

concentration, a decrease in

across

**Anticancer Properties of Cardiac Glycosides**

Cardiac glycosides comprise a large family of naturally derived compounds, the core struc‐ tures of which contain a steroid nucleus with a five-membered lactone ring (cardenolides) or a six-membered lactone ring (bufadienolides) and sugar moieties [1]. A few widely recognized examples of cardiac glycosides are digoxin, digitoxin, ouabain, and oleandrin. The cardeno‐ lides digitoxin and digoxin, two well-known cardiac glycosides, are inhibitors of the plasma

Epidemiologic evidence suggests that breast cancer patients who were treated with digitalis have a significantly lower mortality rate, and their cancer cells had more benign characteristics than those from patients not treated with digitalis [3,4]. Interestingly, the concentrations of cardiac glycosides used for cancer treatment are extremely close to those found in the plasma of cardiac patients treated with the same drugs, suggesting that the anticancer effects of these drugs are exerted at non-toxic concentrations [5]. Furthermore, studies have suggested that cardiac glycosides target cancer cells selectively [6]. These encouraging findings have gained considerable attention in the field of anticancer research, and subsequent studies on the anticancer properties of these compounds have been conducted. These studies investigated not only digoxin and digitoxin but also other related cardiac glycosides, such as ouabain, oleandrin, proscillaridin A, and bufalin [7-10]. Several mechanisms of action, including the inhibition of cancer cell proliferation, the induction of apoptosis, and chemotherapy sensiti‐ zation, have been reported in a large number of published articles that support the potential use of these compounds for cancer treatment [11-14]. However, further clinical studies are still ongoing to better characterize the pharmacological and safety issues associated with these compounds. This chapter provides an overview of the anticancer activities of cardiac glyco‐

positive inotropic effects help suppress the active counter-transportation of Na+

the cell membrane, leading to an increase in the intracellular Na+


concentration, and a consequent increase in cardiac contraction [2].

© 2013 Pongrakhananon; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

and reproduction in any medium, provided the original work is properly cited.

Additional information is available at the end of the chapter

Varisa Pongrakhananon

http://dx.doi.org/10.5772/55381

**1. Introduction**

membrane Na+

the intracellular K+

/K+

### **Anticancer Properties of Cardiac Glycosides**

### Varisa Pongrakhananon

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/55381

### **1. Introduction**

Cardiac glycosides comprise a large family of naturally derived compounds, the core struc‐ tures of which contain a steroid nucleus with a five-membered lactone ring (cardenolides) or a six-membered lactone ring (bufadienolides) and sugar moieties [1]. A few widely recognized examples of cardiac glycosides are digoxin, digitoxin, ouabain, and oleandrin. The cardeno‐ lides digitoxin and digoxin, two well-known cardiac glycosides, are inhibitors of the plasma membrane Na+ /K+ -ATPase that are clinically used for the treatment of heart failure. Their positive inotropic effects help suppress the active counter-transportation of Na+ and K+ across the cell membrane, leading to an increase in the intracellular Na+ concentration, a decrease in the intracellular K+ concentration, and a consequent increase in cardiac contraction [2]. Epidemiologic evidence suggests that breast cancer patients who were treated with digitalis have a significantly lower mortality rate, and their cancer cells had more benign characteristics than those from patients not treated with digitalis [3,4]. Interestingly, the concentrations of cardiac glycosides used for cancer treatment are extremely close to those found in the plasma of cardiac patients treated with the same drugs, suggesting that the anticancer effects of these drugs are exerted at non-toxic concentrations [5]. Furthermore, studies have suggested that cardiac glycosides target cancer cells selectively [6]. These encouraging findings have gained considerable attention in the field of anticancer research, and subsequent studies on the anticancer properties of these compounds have been conducted. These studies investigated not only digoxin and digitoxin but also other related cardiac glycosides, such as ouabain, oleandrin, proscillaridin A, and bufalin [7-10]. Several mechanisms of action, including the inhibition of cancer cell proliferation, the induction of apoptosis, and chemotherapy sensiti‐ zation, have been reported in a large number of published articles that support the potential use of these compounds for cancer treatment [11-14]. However, further clinical studies are still ongoing to better characterize the pharmacological and safety issues associated with these compounds. This chapter provides an overview of the anticancer activities of cardiac glyco‐

© 2013 Pongrakhananon; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

sides and describes the selectivity of these compounds, which could prove to be promising treatments in cancer therapy.

A digitalis preparation from *Digitalis purpurea* was first used for the treatment of congestive heart failure by William Withering in 1785 [23]. Currently, digoxin is recognized as a primary treatment for patients with heart failure. Its mode of action has been identified as the potent

of the cell using ATP as an energy source. This pump plays a vital role, acting as a secondary transporter of nutrients such as glucose and amino acids and helping to maintain the electro‐

level in response to cardiac glycosides stimulates the Na+

mechanism. As a result, the intracellular Ca2+ concentration is increased, consequently promoting cellular events such as myocardial contractibility, accounting for the positive

molecules or for the formation of a signalosome complex that activates various signaling cascades. Several signaling molecules, such as caveolin, SRC kinase, epidermal growth factor receptor (EGFR), and the inositol 1,4,5-triphosphate (IP3) receptor, have been investigated

alterations in these downstream transduction pathways, which could account for the biological

**Name Structure**

/K+

/K+

cation transporter that actively drives two K+ ions into the cell and drives three Na+


concentration low [24]. The elevation of the

Anticancer Properties of Cardiac Glycosides http://dx.doi.org/10.5772/55381



ions out

67

/Ca2+ exchanger

inhibition of Na+

intracellular Na+

• Digoxin (Cardenolide) • From *Digitalis purpurea* • Family: Scrophulariaceae

• Digitoxin (Cardenolide) • From *Digitalis purpurea* • Family: Scrophulariaceae

/K+


chemical gradient by keeping the intracellular Na+

Accumulating evidence has established that the Na+

[25-27]. The inhibitory effects of cardiac glycosides on Na+

properties of these compounds, including their anticancer activities.

inotropic effects of the cardiac glycosides.

/K+

### **2. The chemistry of cardiac glycosides and their biological activities**

Cardiac glycosides from both plants and animals have been known for over one hundred years [14]. Major plant-derived cardiac glycosides include digitoxin, digoxin, ouabain, oleandrin and proscillaridin, which are extracted from the plant families Scrophulariaceae, Apocynaceae, and Asparagaceae (*Digitalis purpurea*, *Digitalis lanata*, *Strophanthus gratus*, *Nerium oleander* and *Urginea maritima*). These compounds consist of a steroidal nucleus linked with a sugar at position 3 (C3) and a lactone ring at position 17 (C17) (Fig 1) [15]. The various types of sugar moieties and lactones provide a large number of cardiac glycosides that, based on their lactone moieties, can be divided into two sub-groups: cardenolides, which contain a five-membered unsaturated butyrolactone ring, and bufadienolides, which contain a six-membered unsatu‐ rated pyrone ring. The core steroidal portion of each molecule has an A/B and C/D cisconformation, which has significant pharmacological relevance. The attached sugars, such as glucose, galactose, mannose, rhamnose, and digitalose, determine the pharmacodynamic and pharmacokinetic activities of each cardiac glycoside.

**Figure 1.** Structural characteristics of cardiac glycosides

Cardiac glycosides have been found in animals as well as plants; for example, bufadienolide was isolated from the venom of a toad species [16], and endogenous digitalis-like compounds have been found in mammalian tissues [17,18]. Several studies have reported that ouabain and proscillaridin A are found in human plasma, that digoxin and marinobufagenin are present in human urine, and that 19-norbufalin exists in cataractous human lenses [18-22]. Table 1 presents a list of the cardiac glycosides found in plants and animals along with their chemical structures.

A digitalis preparation from *Digitalis purpurea* was first used for the treatment of congestive heart failure by William Withering in 1785 [23]. Currently, digoxin is recognized as a primary treatment for patients with heart failure. Its mode of action has been identified as the potent inhibition of Na+ /K+ -ATPase. Na+ /K+ -ATPase, a ubiquitous transmembrane enzyme, is a p-type cation transporter that actively drives two K+ ions into the cell and drives three Na+ ions out of the cell using ATP as an energy source. This pump plays a vital role, acting as a secondary transporter of nutrients such as glucose and amino acids and helping to maintain the electro‐ chemical gradient by keeping the intracellular Na+ concentration low [24]. The elevation of the intracellular Na+ level in response to cardiac glycosides stimulates the Na+ /Ca2+ exchanger mechanism. As a result, the intracellular Ca2+ concentration is increased, consequently promoting cellular events such as myocardial contractibility, accounting for the positive inotropic effects of the cardiac glycosides.

sides and describes the selectivity of these compounds, which could prove to be promising

Cardiac glycosides from both plants and animals have been known for over one hundred years [14]. Major plant-derived cardiac glycosides include digitoxin, digoxin, ouabain, oleandrin and proscillaridin, which are extracted from the plant families Scrophulariaceae, Apocynaceae, and Asparagaceae (*Digitalis purpurea*, *Digitalis lanata*, *Strophanthus gratus*, *Nerium oleander* and *Urginea maritima*). These compounds consist of a steroidal nucleus linked with a sugar at position 3 (C3) and a lactone ring at position 17 (C17) (Fig 1) [15]. The various types of sugar moieties and lactones provide a large number of cardiac glycosides that, based on their lactone moieties, can be divided into two sub-groups: cardenolides, which contain a five-membered unsaturated butyrolactone ring, and bufadienolides, which contain a six-membered unsatu‐ rated pyrone ring. The core steroidal portion of each molecule has an A/B and C/D cisconformation, which has significant pharmacological relevance. The attached sugars, such as glucose, galactose, mannose, rhamnose, and digitalose, determine the pharmacodynamic and

**2. The chemistry of cardiac glycosides and their biological activities**

treatments in cancer therapy.

66 Cancer Treatment - Conventional and Innovative Approaches

pharmacokinetic activities of each cardiac glycoside.

Bufadienolides Cardenolides

Cardiac glycosides have been found in animals as well as plants; for example, bufadienolide was isolated from the venom of a toad species [16], and endogenous digitalis-like compounds have been found in mammalian tissues [17,18]. Several studies have reported that ouabain and proscillaridin A are found in human plasma, that digoxin and marinobufagenin are present in human urine, and that 19-norbufalin exists in cataractous human lenses [18-22]. Table 1 presents a list of the cardiac glycosides found in plants and animals along with their chemical

**Figure 1.** Structural characteristics of cardiac glycosides

structures.

Accumulating evidence has established that the Na+ /K+ -ATPase acts as a scaffold for signaling molecules or for the formation of a signalosome complex that activates various signaling cascades. Several signaling molecules, such as caveolin, SRC kinase, epidermal growth factor receptor (EGFR), and the inositol 1,4,5-triphosphate (IP3) receptor, have been investigated [25-27]. The inhibitory effects of cardiac glycosides on Na+ /K+ -ATPase activity might lead to alterations in these downstream transduction pathways, which could account for the biological properties of these compounds, including their anticancer activities.


**Name Structure**

Anticancer Properties of Cardiac Glycosides http://dx.doi.org/10.5772/55381 69

• Cinobufagin (Bufadienolide) • From *Bufo bufo gargarizans*

• Family: Bufonidae

• Bufalin (Bufadienolide) • From Bufo gargarizans • Family: Bufonidae

• Marinobufagenin (Bufadienolide)

**Table 1.** The chemical structures of cardiac glycosides

• From Bufo marinus • Family: Bufonidae


**Name Structure**

Ouabain (Cardenolide) From *Nerium oleander* Family: Apocynaceae

68 Cancer Treatment - Conventional and Innovative Approaches

• Oleandrin (Cardenolide) • From *Nerium oleander* • Family: Apocynaceae

• Proscillaridin (Bufadienolide) • From *Urginea maritima* • Family: Liliaceae

• Family: Bufonidae

**Table 1.** The chemical structures of cardiac glycosides

### **3. Clinical analysis of the effects of cardiac glycosides on cancers**

melanoma cells in the G2/M phase of the cell cycle [34]. In lung cancer cells, bufalin upregulates p21 WAF1 and suppresses cyclin D expression in response to the activation of p53 [35]. Because the tumor suppressor p21 WAF1 acts as a potent inhibitor of cell cycle progression [36] and because cyclin D1 is a subunit of cyclin dependent kinase (Cdk)-4 and Cdk-6, which are responsible for cell cycle progression from G1 to S phase [37], these changes prevent cells from

Likewise, digitoxin causes cell cycle arrest in G2/M in a dose-dependent manner, resulting in a large increase in the number of cells in the sub-G0 phase [38]. A synthetic monosaccharide analog of digitoxin, D6-MA, has 5-fold greater potency than digitoxin. The mode of action of D6-MA has been reported to involve the downregulation of key elements required for cell replication, including cyclin B1, cdc2 and survivin. It has been suggested that these events might be downstream signaling events resulting from the modulation of second messengers, such as tyrosine kinase Src, PI3K, phospholipase C and Ras/MAPK pathway components, by

An antiproliferative effect of ouabain against human breast and prostate cancer cells has also

and a degradation-dependent pathway, which in turn elevates the level of the cell cycle

role in determining the rate of cell growth. Additional mechanistic studies have demonstrated that an increase in the intracellular Ca2+ concentration following treatment with digoxin, digitoxin, or ouabain is associated with the antiproliferative effects of these compounds in androgen-dependent and androgen-independent prostate cancer cell lines [40]. Because Ca2+ serves as a mediator in several signaling pathways, the elevation of the Ca2+ concentration may stimulate cellular processes that switch the cells into a growth-retarded state. Several of the

Resistance to apoptosis in response to stress conditions is a basic feature of cancer cells and results from the overactivation of survival pathways or the attenuation of cell death mecha‐ nisms. The primary readout for screens of anticancer agents is thus usually an apoptosisinducing effect. Cardiac glycosides have been established as cytotoxic agents that are active

cardiac glycosides triggers the formation of the signalosome complex, contributing to the

It is well documented that apoptosis generally occurs through two main pathways: the mitochondrial-dependent and death receptor-dependent pathways [46]. Gan and colleagues have reported that oleandrin induces cervical cell apoptosis through the mitochondrial cell death mechanism [47]. This compound significantly stimulates the caspase-dependent pathway by triggering the cleavage of caspase-3/7, -6, and -9 and by upregulating the proa‐ poptotic factor Bim. Similarly, data reported by Elbaz and colleagues support the hypothesis that digitoxin mediates the induction of the mitochondrial apoptotic pathway via caspase-9

/K+

/K+


Anticancer Properties of Cardiac Glycosides http://dx.doi.org/10.5772/55381 71


/K+


entering the next phase of the cycle.

cardiac glycoside-bound Na+

**4.2. Induction of apoptosis**

/K+

been reported [39]. Ouabain mediates the depletion of the Na+

inhibitor p21. It has been suggested that the cellular level of Na+

antiproliferative effects of cardiac glycosides are summarized in Table 2.

against various types of cancers. As mentioned above, the inhibition of Na+

initiation of signaling cascades that favor cell death [25-27].


Epidemiologic evidence for the anticancer effects of digitalis was first reported in 1980 by Stenkvist and colleagues. Their study indicated that breast cancer tissue samples from congestive heart failure patients treated with cardiac glycoside therapy exhibited more benign characteristics than cancer tissue samples from control patients who were not treated with the cardiac glycoside regimen [28]. In addition, 5 years after undergoing mastectomy, the recur‐ rence rate for the cardiac glycoside treated-group was 9.6 times lower than that for the control group [28-29]. Four years later, Glodin and colleagues investigated the mortality in 127 cancer patients who received digitalis therapy. These researchers reported that up to 21 patients in the control group died from cancer, whereas only one member of the digitalis-treated group died [30]. Interestingly, the long-term observations of Stenkvist and colleagues also supported the previous finding that digitalis therapy significantly reduces the mortality rate of breast cancer. Among 32 breast cancer patients treated with digitoxin, only two (6%) died, whereas the control group of 143 patients had 48 cancer-related deaths (34%) [4]. Several types of cancer other than breast cancer have also been examined. Recently, Haux and colleagues published an analytical descriptive study on the antineoplastic effects of cardiac glycosides on leukemia and cancers of the kidney/urinary tract [31]. This study indicated that the doses of cardiac glycosides that are active against cancers are similar to the therapeutic plasma concentrations found in cardiac patients treated with these drugs. These clinical observations have established the benificial outcome of cardiac glycosides for cancer therapy. Although these agents seem to be safe at the doses used for the treatment of cardiac disorders, further supporting evidence is still needed before these compounds can be used clinically.

### **4. Anticancer properties and their mechanisms**

At present, cancer is one of the major causes of death worldwide. Extensive research has been conducted over the last decade in an attempt to identify promising compounds that have anticancer effects. Cardiac glycosides are natural compounds that have been previously documented to be antiarrhythmic agents, and their potential anticancer properties were identified thereafter. Cardiac glycosides have been shown to have anticancer activities during various stages of carcinogenesis. These activities include antiproliferative, pro-apoptotic, and chemotherapy sensitization effects.

### **4.1. Antiproliferative effects**

Aberrant cell growth is recognized as one hallmark of cancer [32]. Excessive cell replication is the basic characteristic of cancer progression that facilitates tumor formation and expansion. Defects in normal growth signals result in the inadequate regulation of cell division, which drives quiescent cells to proliferate [33]. Cardiac glycosides have been demonstrated to have antiproliferative activities via their regulation of the cell cycle. The extract from the skin glands of *Bufo bufo gargarizans*, which contains bufalin, is able to induce arrest in human malignant melanoma cells in the G2/M phase of the cell cycle [34]. In lung cancer cells, bufalin upregulates p21 WAF1 and suppresses cyclin D expression in response to the activation of p53 [35]. Because the tumor suppressor p21 WAF1 acts as a potent inhibitor of cell cycle progression [36] and because cyclin D1 is a subunit of cyclin dependent kinase (Cdk)-4 and Cdk-6, which are responsible for cell cycle progression from G1 to S phase [37], these changes prevent cells from entering the next phase of the cycle.

Likewise, digitoxin causes cell cycle arrest in G2/M in a dose-dependent manner, resulting in a large increase in the number of cells in the sub-G0 phase [38]. A synthetic monosaccharide analog of digitoxin, D6-MA, has 5-fold greater potency than digitoxin. The mode of action of D6-MA has been reported to involve the downregulation of key elements required for cell replication, including cyclin B1, cdc2 and survivin. It has been suggested that these events might be downstream signaling events resulting from the modulation of second messengers, such as tyrosine kinase Src, PI3K, phospholipase C and Ras/MAPK pathway components, by cardiac glycoside-bound Na+ /K+ -ATPase [25-27].

An antiproliferative effect of ouabain against human breast and prostate cancer cells has also been reported [39]. Ouabain mediates the depletion of the Na+ /K+ -ATPase through endocytosis and a degradation-dependent pathway, which in turn elevates the level of the cell cycle inhibitor p21. It has been suggested that the cellular level of Na+ /K+ -ATPase plays an important role in determining the rate of cell growth. Additional mechanistic studies have demonstrated that an increase in the intracellular Ca2+ concentration following treatment with digoxin, digitoxin, or ouabain is associated with the antiproliferative effects of these compounds in androgen-dependent and androgen-independent prostate cancer cell lines [40]. Because Ca2+ serves as a mediator in several signaling pathways, the elevation of the Ca2+ concentration may stimulate cellular processes that switch the cells into a growth-retarded state. Several of the antiproliferative effects of cardiac glycosides are summarized in Table 2.

### **4.2. Induction of apoptosis**

**3. Clinical analysis of the effects of cardiac glycosides on cancers**

70 Cancer Treatment - Conventional and Innovative Approaches

is still needed before these compounds can be used clinically.

**4. Anticancer properties and their mechanisms**

chemotherapy sensitization effects.

**4.1. Antiproliferative effects**

Epidemiologic evidence for the anticancer effects of digitalis was first reported in 1980 by Stenkvist and colleagues. Their study indicated that breast cancer tissue samples from congestive heart failure patients treated with cardiac glycoside therapy exhibited more benign characteristics than cancer tissue samples from control patients who were not treated with the cardiac glycoside regimen [28]. In addition, 5 years after undergoing mastectomy, the recur‐ rence rate for the cardiac glycoside treated-group was 9.6 times lower than that for the control group [28-29]. Four years later, Glodin and colleagues investigated the mortality in 127 cancer patients who received digitalis therapy. These researchers reported that up to 21 patients in the control group died from cancer, whereas only one member of the digitalis-treated group died [30]. Interestingly, the long-term observations of Stenkvist and colleagues also supported the previous finding that digitalis therapy significantly reduces the mortality rate of breast cancer. Among 32 breast cancer patients treated with digitoxin, only two (6%) died, whereas the control group of 143 patients had 48 cancer-related deaths (34%) [4]. Several types of cancer other than breast cancer have also been examined. Recently, Haux and colleagues published an analytical descriptive study on the antineoplastic effects of cardiac glycosides on leukemia and cancers of the kidney/urinary tract [31]. This study indicated that the doses of cardiac glycosides that are active against cancers are similar to the therapeutic plasma concentrations found in cardiac patients treated with these drugs. These clinical observations have established the benificial outcome of cardiac glycosides for cancer therapy. Although these agents seem to be safe at the doses used for the treatment of cardiac disorders, further supporting evidence

At present, cancer is one of the major causes of death worldwide. Extensive research has been conducted over the last decade in an attempt to identify promising compounds that have anticancer effects. Cardiac glycosides are natural compounds that have been previously documented to be antiarrhythmic agents, and their potential anticancer properties were identified thereafter. Cardiac glycosides have been shown to have anticancer activities during various stages of carcinogenesis. These activities include antiproliferative, pro-apoptotic, and

Aberrant cell growth is recognized as one hallmark of cancer [32]. Excessive cell replication is the basic characteristic of cancer progression that facilitates tumor formation and expansion. Defects in normal growth signals result in the inadequate regulation of cell division, which drives quiescent cells to proliferate [33]. Cardiac glycosides have been demonstrated to have antiproliferative activities via their regulation of the cell cycle. The extract from the skin glands of *Bufo bufo gargarizans*, which contains bufalin, is able to induce arrest in human malignant

Resistance to apoptosis in response to stress conditions is a basic feature of cancer cells and results from the overactivation of survival pathways or the attenuation of cell death mecha‐ nisms. The primary readout for screens of anticancer agents is thus usually an apoptosisinducing effect. Cardiac glycosides have been established as cytotoxic agents that are active against various types of cancers. As mentioned above, the inhibition of Na+ /K+ -ATPase by cardiac glycosides triggers the formation of the signalosome complex, contributing to the initiation of signaling cascades that favor cell death [25-27].

It is well documented that apoptosis generally occurs through two main pathways: the mitochondrial-dependent and death receptor-dependent pathways [46]. Gan and colleagues have reported that oleandrin induces cervical cell apoptosis through the mitochondrial cell death mechanism [47]. This compound significantly stimulates the caspase-dependent pathway by triggering the cleavage of caspase-3/7, -6, and -9 and by upregulating the proa‐ poptotic factor Bim. Similarly, data reported by Elbaz and colleagues support the hypothesis that digitoxin mediates the induction of the mitochondrial apoptotic pathway via caspase-9


indicated that a low dose of ouabain was able to upregulate prostate apoptosis response 4,

Other mechanisms of cardiac glycoside-induced apoptosis have also been reported (Fig 2). Mitogen-activated protein kinases (MAPKs) have been reported to be targeted in bufulininduced human leukemia cell apoptosis [54]. JNK and AP-1 are transcription factors that activate the transcription of various genes, including apoptosis-related genes [55,56]. In response to bufalin treatment, the MAPK signaling pathway is triggered, leading to a notable

> Induction of mitochondrial pathway [38,47]

Inhibition of Up g re ulation

Cardiac glycosides

[54,57] [53,58-59]

of death receptor [49-50]

Anticancer Properties of Cardiac Glycosides http://dx.doi.org/10.5772/55381 73

Activation of MAPK pathway [54 57]

which is required to reach the desired level of apoptotic cell death.

NF-kB pathway [43-44,49]

> Induction or reactive oxygen species

**Figure 2.** Molecular mechanisms of cardiac glycoside-induced apoptosis

elevation in the activities of c-Jun N-terminal protein kinase (JNK) and AP-1.

#### **Table 2.** Antiproliferative effects of cardiac glycosides

activation [38]. This study demonstrated not only a cell growth inhibitory effect but also an apoptotic induction effect for digitoxin.

Fas and TNF-related apoptosis-inducing ligand (TRAIL) are important mediators of the death receptor pathway, and the deregulation of their expression is a major cause of chemoresistance and immune escape in cancers [48]. Recently, Sreenivasna and colleagues investigated whether oleandrin triggers the expression of the Fas receptor to potentiate apoptosis in cancer cells without affecting normal primary cells [49]. Additionally, oleandrin has been found to be able to attenuate the NF-kB pathway, which is a key pathway with antiapoptosis and pro-prolif‐ erative effects. Cardiac glycosides including oleandrin, bufalin, digitoxin, and digoxin also initiate apoptosis through Apo2L/TRAIL by elevating the levels of death receptors 4 and 5 in non-small cell lung cancer cells [50]. Interestingly, both Fas and Apo2L/TRAIL induce apoptosis in cancer cells but have little to no effect on normal cells. Furthermore, our recent work has demonstrated that ouabain was able to increse TRAIL-mediated lung cancer cell death through anti-apoptosis Mcl-1 down-regulation [51]. Because of these results, cardiac glycosides are of great interest in the field of cancer research.

A growing number of studies have indicated that the disruption of the oxidative state inside cancer cells, due to either the suppression of the antioxidant system or the introduction of reactive oxygen species, can lead to cell death [52]. In androgen-independent prostate cancer cells, ouabain triggers apoptosis by interfering with mitochondrial function [53]. Because the mitochondria are a major source of reactive oxygen species, the application of ouabain causes a steady increase in the level of these species, which leads to apoptosis. This study also indicated that a low dose of ouabain was able to upregulate prostate apoptosis response 4, which is required to reach the desired level of apoptotic cell death.

Other mechanisms of cardiac glycoside-induced apoptosis have also been reported (Fig 2). Mitogen-activated protein kinases (MAPKs) have been reported to be targeted in bufulininduced human leukemia cell apoptosis [54]. JNK and AP-1 are transcription factors that activate the transcription of various genes, including apoptosis-related genes [55,56]. In response to bufalin treatment, the MAPK signaling pathway is triggered, leading to a notable elevation in the activities of c-Jun N-terminal protein kinase (JNK) and AP-1.

**Figure 2.** Molecular mechanisms of cardiac glycoside-induced apoptosis

activation [38]. This study demonstrated not only a cell growth inhibitory effect but also an

Fas and TNF-related apoptosis-inducing ligand (TRAIL) are important mediators of the death receptor pathway, and the deregulation of their expression is a major cause of chemoresistance and immune escape in cancers [48]. Recently, Sreenivasna and colleagues investigated whether oleandrin triggers the expression of the Fas receptor to potentiate apoptosis in cancer cells without affecting normal primary cells [49]. Additionally, oleandrin has been found to be able to attenuate the NF-kB pathway, which is a key pathway with antiapoptosis and pro-prolif‐ erative effects. Cardiac glycosides including oleandrin, bufalin, digitoxin, and digoxin also initiate apoptosis through Apo2L/TRAIL by elevating the levels of death receptors 4 and 5 in non-small cell lung cancer cells [50]. Interestingly, both Fas and Apo2L/TRAIL induce apoptosis in cancer cells but have little to no effect on normal cells. Furthermore, our recent work has demonstrated that ouabain was able to increse TRAIL-mediated lung cancer cell death through anti-apoptosis Mcl-1 down-regulation [51]. Because of these results, cardiac

A growing number of studies have indicated that the disruption of the oxidative state inside cancer cells, due to either the suppression of the antioxidant system or the introduction of reactive oxygen species, can lead to cell death [52]. In androgen-independent prostate cancer cells, ouabain triggers apoptosis by interfering with mitochondrial function [53]. Because the mitochondria are a major source of reactive oxygen species, the application of ouabain causes a steady increase in the level of these species, which leads to apoptosis. This study also

apoptotic induction effect for digitoxin.

**Table 2.** Antiproliferative effects of cardiac glycosides

glycosides are of great interest in the field of cancer research.

**Cardiac glycoside Mechanism**

cdc2 and survivin [38]

72 Cancer Treatment - Conventional and Innovative Approaches

Digoxin Increase in the intracellular Ca2+ concentration [40]

Ouabain Depletion of Na+/K+-ATPase and upregulation of p21 [39]

concentration [41]

concentration [41]

concentration [41]

Digitoxin Induction of cell cycle arrest in G2/M phase through the downregulation of cyclin B1,

Inhibition of DNA topoisomerases I and II and an increase in the intracellular Ca2+

Inhibition of DNA topoisomerases I and II and increase in the intracellular Ca2+

Induction of cell cycle arrest through the upregulation of HIF-1α [42]

Increase in the intracellular Ca2+ concentration [40]

Increase in the intracellular Ca2+ concentration [40]

p53 and the downregulation of cyclin D [34,35] Inhibition of DNA topoisomerases I and II [45] Proscillaridin A Inhibition of DNA topoisomerases I and II and an increase in the intracellular Ca2+

Oleandrin Attenuation of NF-kB, JNK and AP-1 (nuclear transcription factors) activation [43,44] Bufalin Induction of cell cycle arrest in G2/M phase through the upregulation of p21 WAF1 and

### **4.3. Sensitization to chemotherapy and enhancement of radiotherapy sensitivity**

The susceptibility of a given cancer to chemotherapy often appears to decrease after several rounds of chemotherapy. Resistance to drug-induced cell death is therefore a critical problem in cancer therapy. Combination therapy may be initiated as an alternative approach to overcome this problem. Furthermore, the use of combination therapy increases the cytotoxicity of anticancer agents and reduces their serious side effects on normal cells by reducing the dosage required for each individual agent. Cardiac glycosides have beneficial effects when used as part of combination therapies. Felth and colleagues have investigated the cytotoxicities of cardiac glycosides alone and in combination with various clinically relevant anticancer drugs [60]. Of the glycosides tested, convallatoxin, oleandrin, and proscillaridin A have been shown to be the most potent inducers of colon cancer cell death. Furthermore, co-treatment with cardiac glycosides, including digoxin, digitoxin, oleandrin, and digitonin, and other anticancer drugs, namely 5-fluorouracil, oxaliplatin, cisplatin, and irinotecan, was shown to result in a substantial increase in cancer cell death. However, this study was only a primary screen of the effects of these compounds, and the mechanisms responsible for these effects have not been elucidated.

cells are exposed to ouabain after irradiation. These events are the results of the inhibitory

The ideal anticancer agent would not only be effective but also selective against tumor cells. As emphasized above, cardiac glycosides have beneficial anticancer effects but do not affect normal cells. Oleandrin attenuates the activation of nuclear transcription factor-kB and activator protein-1 and mediates ceramide-induced apoptosis [43]. These effects are apparently specific to human tumor cells. Consistent with the above findings, bufalin selectively kills leukemia cells, whereas normal leukocytes remain largely unharmed [66, 67]. Furthermore, cardiac glycosides have also been shown to exhibit selectivity in sensitizing cancer cells to apoptosis during radiation treatment. Large numbers of tumor cells and transformed cells die in response to radiation following ouabain pretreatment, but normal cells do not [63, 65]. These studies support the hypothesis that cardiac glycosides have selective anticancer effects,

This selective killing effect has received attention in the search for the fundamental differences between cancer cells and normal cells that modulate the survival pathway. One attempt to

dissimilar in rodent and human cancer cells, affecting the sensitivity to apoptosis induced by

subunit and the glycosylated β subunit. It is well known that the α subunit serves as a binding

of heterodimer assembly and insertion into the plasma membrane [69, 70]. Recent data indicate that the α1 and α3 subunits are commonly expressed in human tumor cells, whereas only α1 can be found in rodent tumor cell lines [71,72]. It has also been suggested that the lack of the α3 subunit in rodent cancer cells causes resistance to apoptosis mediated by cardiac glycosides. This finding strengthens the hypothesis that normal cells might have lower α3 subunit expression levels than cancer cells, accounting for the selective anticancer effects of cardiac glycosides. Furthermore, it has been demonstrated that the biological activity of cardiac glycosides results from the binding of these compounds with all α subunits, but the α3 subunit is a favorable target [73]. Ouabain, for example, has a 1000-fold stronger interaction with the

Expanding on the above findings, that the expression of the α3 subunit has been shown to increase concurrent with the decrease in α1 subunit expression in human colorectal cancer and colon adenoma cell lines, whereas no significant alteration of α3 subunit expression is detected in normal kidney and renal cells [75]. These results indicate that the overexpression of the α3 subunit is associated with responsiveness to cardiac glycosides. Because all α subunits are commonly expressed at a basal level in cancers, the α3/α1 ratio might be a marker of cell sensitivity to cardiac glycosides, and this ratio could be determined in tumor biopsy samples taken prior to treatment with cardiac glycosides [76]. A lower α3/α1 ratio may indicate unresponsiveness to cardiac glycosides; conversely, cardiac glycoside treatment may improve

the clinical outcomes of patients who have tumor tissues with higher ratios.

/K+

Anticancer Properties of Cardiac Glycosides http://dx.doi.org/10.5772/55381 75


and ATP, whereas the β subunit plays a role in the regulation


identify such differences demonstrated that the subunit composition of Na+

/K+

, K+

effect of ouabain on the G2/M phase of the cell cycle.

**4.4. The selectivity and sensitivity of cardiac glycosides for cancer cells**

suggesting that these compounds have potential clinical uses.

cardiac glycosides [68]. The Na+

α3 isoform than the α1 isoform [74].

site for cardiac glycosides, Na+

It is significant that the members of the ATP binding cassette family of transporters, including ABCC7 (CFTR), ABCB1 (P-glycoprotein), and ABCC1 (MRP1), play critical roles in pumping a broad range of drugs out of cells and that these transporters are obviously overexpressed in several tumors [61]. Ouabain has been identified in a recent study to be able to regulate both the expression and activity of ABCC1 in an embryonic kidney cell line. The impairment of ABCC1 following ouabain treatment suggests that this compound might be able to prevent the reduction of the therapeutic concentration inside target cells.

Radiotherapy is a traditional approach used to destroy localized and unresectable tumor cells and to prevent these cells from metastasizing. The combination of chemotherapy and radiation limits the aggressiveness of cancers and increases the patient survival rate. The basic concept underlying chemoradiation is that chemotherapeutics are administered to make cancer cells more susceptible to radiation. Unfortunately, most cancers develop chemoresistance, and anticancer agents have serious side effects in normal cells. The administration of potent anticancer agents with less toxicity against normal cells to sensitize the tumor cells to readio‐ therapy is a promising strategy. Cardiac glycosides are substances that exhibit selectivity and significant activity against cancer cell lines; thus, the addition of these compounds to existing chemoradiation regimens has been investigated. Huachansu, which is extracted from the skin glands of *Bufo bufo gargarizans,* exhibits a radiosensitizing effect on human lung cancer cells [62]. This Chinese medicine contains a group of steroidal cardiac glycosides and substantially increases radiation-mediated cell death via a p53-dependent pathway. The underlying mechanism involves the cleavage of caspase-3 and poly-(ADP-ribose) polymerase (PARP) concurrent with the downregulation of the antiapoptotic protein Bcl-2 and the inhibition of DNA repair.

The ability of ouabain to sensitize cancer cells to radiotherapy has also been established. Transformed fibroblasts and tumor cells exposed to gamma radiation undergo apoptosis in the presence of ouabain [63-65]. In addition, the recovery of cells is clearly delayed when the cells are exposed to ouabain after irradiation. These events are the results of the inhibitory effect of ouabain on the G2/M phase of the cell cycle.

### **4.4. The selectivity and sensitivity of cardiac glycosides for cancer cells**

**4.3. Sensitization to chemotherapy and enhancement of radiotherapy sensitivity**

have not been elucidated.

74 Cancer Treatment - Conventional and Innovative Approaches

DNA repair.

The susceptibility of a given cancer to chemotherapy often appears to decrease after several rounds of chemotherapy. Resistance to drug-induced cell death is therefore a critical problem in cancer therapy. Combination therapy may be initiated as an alternative approach to overcome this problem. Furthermore, the use of combination therapy increases the cytotoxicity of anticancer agents and reduces their serious side effects on normal cells by reducing the dosage required for each individual agent. Cardiac glycosides have beneficial effects when used as part of combination therapies. Felth and colleagues have investigated the cytotoxicities of cardiac glycosides alone and in combination with various clinically relevant anticancer drugs [60]. Of the glycosides tested, convallatoxin, oleandrin, and proscillaridin A have been shown to be the most potent inducers of colon cancer cell death. Furthermore, co-treatment with cardiac glycosides, including digoxin, digitoxin, oleandrin, and digitonin, and other anticancer drugs, namely 5-fluorouracil, oxaliplatin, cisplatin, and irinotecan, was shown to result in a substantial increase in cancer cell death. However, this study was only a primary screen of the effects of these compounds, and the mechanisms responsible for these effects

It is significant that the members of the ATP binding cassette family of transporters, including ABCC7 (CFTR), ABCB1 (P-glycoprotein), and ABCC1 (MRP1), play critical roles in pumping a broad range of drugs out of cells and that these transporters are obviously overexpressed in several tumors [61]. Ouabain has been identified in a recent study to be able to regulate both the expression and activity of ABCC1 in an embryonic kidney cell line. The impairment of ABCC1 following ouabain treatment suggests that this compound might be able to prevent

Radiotherapy is a traditional approach used to destroy localized and unresectable tumor cells and to prevent these cells from metastasizing. The combination of chemotherapy and radiation limits the aggressiveness of cancers and increases the patient survival rate. The basic concept underlying chemoradiation is that chemotherapeutics are administered to make cancer cells more susceptible to radiation. Unfortunately, most cancers develop chemoresistance, and anticancer agents have serious side effects in normal cells. The administration of potent anticancer agents with less toxicity against normal cells to sensitize the tumor cells to readio‐ therapy is a promising strategy. Cardiac glycosides are substances that exhibit selectivity and significant activity against cancer cell lines; thus, the addition of these compounds to existing chemoradiation regimens has been investigated. Huachansu, which is extracted from the skin glands of *Bufo bufo gargarizans,* exhibits a radiosensitizing effect on human lung cancer cells [62]. This Chinese medicine contains a group of steroidal cardiac glycosides and substantially increases radiation-mediated cell death via a p53-dependent pathway. The underlying mechanism involves the cleavage of caspase-3 and poly-(ADP-ribose) polymerase (PARP) concurrent with the downregulation of the antiapoptotic protein Bcl-2 and the inhibition of

The ability of ouabain to sensitize cancer cells to radiotherapy has also been established. Transformed fibroblasts and tumor cells exposed to gamma radiation undergo apoptosis in the presence of ouabain [63-65]. In addition, the recovery of cells is clearly delayed when the

the reduction of the therapeutic concentration inside target cells.

The ideal anticancer agent would not only be effective but also selective against tumor cells. As emphasized above, cardiac glycosides have beneficial anticancer effects but do not affect normal cells. Oleandrin attenuates the activation of nuclear transcription factor-kB and activator protein-1 and mediates ceramide-induced apoptosis [43]. These effects are apparently specific to human tumor cells. Consistent with the above findings, bufalin selectively kills leukemia cells, whereas normal leukocytes remain largely unharmed [66, 67]. Furthermore, cardiac glycosides have also been shown to exhibit selectivity in sensitizing cancer cells to apoptosis during radiation treatment. Large numbers of tumor cells and transformed cells die in response to radiation following ouabain pretreatment, but normal cells do not [63, 65]. These studies support the hypothesis that cardiac glycosides have selective anticancer effects, suggesting that these compounds have potential clinical uses.

This selective killing effect has received attention in the search for the fundamental differences between cancer cells and normal cells that modulate the survival pathway. One attempt to identify such differences demonstrated that the subunit composition of Na+ /K+ -ATPase is dissimilar in rodent and human cancer cells, affecting the sensitivity to apoptosis induced by cardiac glycosides [68]. The Na+ /K+ -ATPase consists of two main subunits, the catalytic α subunit and the glycosylated β subunit. It is well known that the α subunit serves as a binding site for cardiac glycosides, Na+ , K+ and ATP, whereas the β subunit plays a role in the regulation of heterodimer assembly and insertion into the plasma membrane [69, 70]. Recent data indicate that the α1 and α3 subunits are commonly expressed in human tumor cells, whereas only α1 can be found in rodent tumor cell lines [71,72]. It has also been suggested that the lack of the α3 subunit in rodent cancer cells causes resistance to apoptosis mediated by cardiac glycosides. This finding strengthens the hypothesis that normal cells might have lower α3 subunit expression levels than cancer cells, accounting for the selective anticancer effects of cardiac glycosides. Furthermore, it has been demonstrated that the biological activity of cardiac glycosides results from the binding of these compounds with all α subunits, but the α3 subunit is a favorable target [73]. Ouabain, for example, has a 1000-fold stronger interaction with the α3 isoform than the α1 isoform [74].

Expanding on the above findings, that the expression of the α3 subunit has been shown to increase concurrent with the decrease in α1 subunit expression in human colorectal cancer and colon adenoma cell lines, whereas no significant alteration of α3 subunit expression is detected in normal kidney and renal cells [75]. These results indicate that the overexpression of the α3 subunit is associated with responsiveness to cardiac glycosides. Because all α subunits are commonly expressed at a basal level in cancers, the α3/α1 ratio might be a marker of cell sensitivity to cardiac glycosides, and this ratio could be determined in tumor biopsy samples taken prior to treatment with cardiac glycosides [76]. A lower α3/α1 ratio may indicate unresponsiveness to cardiac glycosides; conversely, cardiac glycoside treatment may improve the clinical outcomes of patients who have tumor tissues with higher ratios.

It has been established that the α1 isoform of the Na+ /K+ -ATPase plays a critical role in the progression of non-small cell lung cancer. The suppression of α1 subunit expression by RNA interference attenuates the invasiveness of cancer, reducing both migration and proliferation [77]. In addition, an increase the α1 subunit level enhances sensitivity to cardiac glycosides. In more than half of glioblastoma samples, the level of Na+ /K+ -ATPase α1 mRNA was markedly elevated, up to 10 times greater than that in normal samples [78]. Similarly, significant upregulation of the α1 isoform was observed in metastatic melanoma cell lines and melanoma tissue samples [79, 80]. These results indicate that the responsiveness of either cancer cells or normal cells to cardiac glycosides based on the α3/α1 ratio is tissue specific. It is important to determine the differences in the expression levels of the α subunits between cancer cells and normal cells. Furthermore, the characterization of the specificity of each cardiac glycoside for each enzyme subunit is necessary to identify cancers with the appropriate α3/α1 expression pattern for treatment and to reduce the effect on normal cells, thus optimizing the effectiveness of cardiac glycosides as potent anticancer drugs.

**Acknowledgements**

and Dr. Pithi Chanvorachote.

**Author details**

Bangkok, Thailand

**References**

Varisa Pongrakhananon

1403-1417.

493-496.

1043-1053.

Pharmacology 2004;67 727-733.

peutic 2009;8 2319-2328.

cine. 1997;337 129-130.

This work was supported by a Grant for Development of New Faculty Staff, Chulalongkorn University, and the Thailand Research Fund. The author wishes to thank Dr. Yon Rojanasakul

Cell-based Drug and Health Product Development Research Unit, Department of Pharma‐ cology and Physiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University,

targets in anticancer therapy. Expert Opinion on Therapeutic Targets 2008;12

[2] Böhm M. Digoxin in patients with heart failure. The New England Journal of Medi‐

[4] Stenkvist B. Is digitalis a therapy for breast carcinoma? Oncology Report 1999;6

[5] Gupta RS, Chopra A, Stetsko DK. Cellular basis for the species differences in sensi‐ tivity to cardiac glycosides (digitalis). Journal of cellular physiology 1986;127 197-206.

[6] López-Lázaro M. Digitoxin as an anticancer agent with selectivity for cancer cells: possible mechanisms involved. Expert Opinion on Therapeutic Targets 2007;11

[7] Huang YT, Chueh SC, Teng CM, Guh JH. Investigation of ouabain-induced anticanc‐ er effect in human androgen-independent prostate cancer PC-3 cells. Biochemical

[8] Yang P, Menter DG, Cartwright C, Chan D, Dixon S, Suraokar M, Mendoza G, Llansa N, Newman RA. Oleandrin-mediated inhibition of human tumor cell proliferation: importance of Na,K-ATPase alpha subunits as drug targets. Molecular Cancer Thera‐

[3] Stenkvist B. Cardenolides and cancer. Anticancer Drugs 2001;12 635-638.

/K+


Anticancer Properties of Cardiac Glycosides http://dx.doi.org/10.5772/55381 77

[1] Mijatovic T, Ingrassia L, Facchini V, Kiss R. Na+

### **5. Conclusion**

Cancer remains a life-threating disease that is typically characterized by frequently related to dysregulated cell growth and resistance to apoptosis. Within the past decade, cancer research has provided interesting insights with the potential to define the exact causes of cancer and to aid in the development of anticancer agents with enhanced effectiveness against and selectivity for cancer. Several plant-derived compounds were once used as ingredients of treatments for diseases without any established scientific evidence to support the claimed effects. Later, these compounds were found to exhibit relevant biological activities. Numerous studies have screened medicinal plants for compounds with anticancer activity, including cardiac glyco‐ sides. Generally, cardiac glycosides are recognized as antiarrhythmic drugs that function by inhibiting Na+ /K+ -ATPase. These compounds have been reported to be therapeutically beneficial for the treatment of various tumor types because of their antiproliferative effects, ability to induce apoptosis, and ability to sensitize cells to chemo/radiotherapy-induced cell death.

As already emphasized, cardiac glycosides have a narrow therapeutic index, which could cause serious cardiovascular toxicity. Interestingly, it has been observed that the concentration required to treat cancer was lower than of that used to treat cardiac disorders. Furthermore, cardiac glycosides appear to exert a cancer-specific killing activity by targeting the Na<sup>+</sup> /K+ - ATPase α subunit in tumor cells. However, the expression pattern of the enzyme subunits and the target specificity of cardiac glycosides must be optimized. Synthetic cardiac glycosides have been designed to achieve the desired effects; these compounds include UNBS-1450 [81,82] and D6-MA [38 ,83]. Although cardiac glycosides have potential effects on cancer, at present, evidence supporting their usefulness is still needed, and the safety profile of cardiac glycosides as anticancer agents must be determined.

### **Acknowledgements**

It has been established that the α1 isoform of the Na+

76 Cancer Treatment - Conventional and Innovative Approaches

more than half of glioblastoma samples, the level of Na+

of cardiac glycosides as potent anticancer drugs.

**5. Conclusion**

inhibiting Na+

death.

/K+

glycosides as anticancer agents must be determined.

/K+

/K+

progression of non-small cell lung cancer. The suppression of α1 subunit expression by RNA interference attenuates the invasiveness of cancer, reducing both migration and proliferation [77]. In addition, an increase the α1 subunit level enhances sensitivity to cardiac glycosides. In

elevated, up to 10 times greater than that in normal samples [78]. Similarly, significant upregulation of the α1 isoform was observed in metastatic melanoma cell lines and melanoma tissue samples [79, 80]. These results indicate that the responsiveness of either cancer cells or normal cells to cardiac glycosides based on the α3/α1 ratio is tissue specific. It is important to determine the differences in the expression levels of the α subunits between cancer cells and normal cells. Furthermore, the characterization of the specificity of each cardiac glycoside for each enzyme subunit is necessary to identify cancers with the appropriate α3/α1 expression pattern for treatment and to reduce the effect on normal cells, thus optimizing the effectiveness

Cancer remains a life-threating disease that is typically characterized by frequently related to dysregulated cell growth and resistance to apoptosis. Within the past decade, cancer research has provided interesting insights with the potential to define the exact causes of cancer and to aid in the development of anticancer agents with enhanced effectiveness against and selectivity for cancer. Several plant-derived compounds were once used as ingredients of treatments for diseases without any established scientific evidence to support the claimed effects. Later, these compounds were found to exhibit relevant biological activities. Numerous studies have screened medicinal plants for compounds with anticancer activity, including cardiac glyco‐ sides. Generally, cardiac glycosides are recognized as antiarrhythmic drugs that function by

beneficial for the treatment of various tumor types because of their antiproliferative effects, ability to induce apoptosis, and ability to sensitize cells to chemo/radiotherapy-induced cell

As already emphasized, cardiac glycosides have a narrow therapeutic index, which could cause serious cardiovascular toxicity. Interestingly, it has been observed that the concentration required to treat cancer was lower than of that used to treat cardiac disorders. Furthermore, cardiac glycosides appear to exert a cancer-specific killing activity by targeting the Na<sup>+</sup>

ATPase α subunit in tumor cells. However, the expression pattern of the enzyme subunits and the target specificity of cardiac glycosides must be optimized. Synthetic cardiac glycosides have been designed to achieve the desired effects; these compounds include UNBS-1450 [81,82] and D6-MA [38 ,83]. Although cardiac glycosides have potential effects on cancer, at present, evidence supporting their usefulness is still needed, and the safety profile of cardiac




/K+ - This work was supported by a Grant for Development of New Faculty Staff, Chulalongkorn University, and the Thailand Research Fund. The author wishes to thank Dr. Yon Rojanasakul and Dr. Pithi Chanvorachote.

### **Author details**

Varisa Pongrakhananon

Cell-based Drug and Health Product Development Research Unit, Department of Pharma‐ cology and Physiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand

### **References**


[9] Winnicka K, Bielawski K, Bielawska A, Miltyk W. Apoptosis-mediated cytotoxicity of ouabain, digoxin and proscillaridin A in the estrogen independent MDA-MB-231 breast cancer cells. Archives of pharmacal research 2007;30 1216-1224.

[22] Schoner W, Scheiner-Bobis G. Endogenous and exogenous cardiac glycosides: their roles in hypertension, salt metabolism, and cell growth. American Journal of Physiol‐

[23] Aronson JK. (1986) An account of the foxglove and its medical uses 1785-1985. Ox‐

[24] Kaplan JH. Biochemistry of Na,K-ATPase. Annual Review of Biochemistry 2002;71

[26] Haas M, Wang H, Tian J, Xie Z. Src-mediated inter-receptor cross-talk between the

[27] Aperia A. New roles for an old enzyme: Na,K-ATPase emerges as an interesting

[29] Stenkvist B: Evidence of a modifying influence of heart glucosides on the develop‐ ment of breast cancer. Analytical and Quantitative Cytology 1980;2 49-54.

[31] Haux J, Klepp O, Spigset O, Tretli S. Digitoxin medication and cancer; case control

[33] Evan GI, Vousden KH. Proliferation, cell cycle and apoptosis in cancer. Nature

[34] Yang P, Chan D, Vijjeswarapu M, Cartwright C, Cohen L, Meng Z, Liu L, Newman RA. Anti-proliferative activity of Huachansu, a Bufo toad skin extract, against human malignant melanoma cells. Proceeding of American Association Cancer Research

[35] Jiang Y, Zhang Y, Luan J, Duan H, Zhang F, Yagasaki K, Zhang G. Effects of bufalin on the proliferation of human lung cancer cells and its molecular mechanisms of ac‐

[36] Pestell RG, Albanese C, Reutens AT, Segall JE, Lee RJ, Arnold A. The cyclins and cy‐ clin-dependent kinase inhibitors in hormonal regulation of proliferation and differ‐

[37] Baldin V, Lukas J, Marcote MJ, Pagano M, Draetta G. Cyclin D1 is a nuclear protein required for cell cycle progression in G1. Genes & Development 1993;7 812-21.


ATPase-mediated signal transduction: from protein interaction

Anticancer Properties of Cardiac Glycosides http://dx.doi.org/10.5772/55381 79

ogy Cell Physiology 2007;293 C509-36.

/K+

to cellular function. Molecular Intervention 2003;3 157-168.

drug target. Journal of Internal Medicine 2007;261 44-52.

[30] Goldin AG, Safa AR: Digitalis and cancer. Lancet 1984;1 1134.

and internal dose-response studies. BMC Cancer 2001;1 11.

[32] Hanahan D, Weinberg RA. The Hallmarks of cancer. Cell 2000:1 57-70.

[28] Stenkvist B. Cardiac glycosides and breast cancer. Lancet 1979;1 563.

ford University Press.

511-35.

Na+ /K+

[25] Xie Z, Cai T. Na+

18694-702.

2001;6835 342-348.

tion. Cytotechnology 2010;62 573-83.

entiation. Endocrine Review 1999;20 501-534.

2006; 47


[22] Schoner W, Scheiner-Bobis G. Endogenous and exogenous cardiac glycosides: their roles in hypertension, salt metabolism, and cell growth. American Journal of Physiol‐ ogy Cell Physiology 2007;293 C509-36.

[9] Winnicka K, Bielawski K, Bielawska A, Miltyk W. Apoptosis-mediated cytotoxicity of ouabain, digoxin and proscillaridin A in the estrogen independent MDA-MB-231

[10] Jiang Y, Zhang Y, Luan J, Duan H, Zhang F, Yagasaki K, Zhang G. Effects of bufalin on the proliferation of human lung cancer cells and its molecular mechanisms of ac‐

[11] Haux J. Digitoxin is a potential anticancer agent for several types of cancer. Medical

[12] Mijatovic T, Dufrasne F, Kiss R. Cardiotonic steroids-mediated targeting of the Na+

[13] Newman RA, Yang P, Pawlus AD, Block KI. Cardiac glycosides as novel cancer ther‐

[14] Prassas I, Diamandis EP. Novel therapeutic applications of cardiac glycosides. Na‐

[15] Schönfeld W, Weiland J, Lindig C, Masnyk M, Kabat MM, Kurek A, Wicha J, Repke KR. The lead structure in cardiac glycosides is 5a,14a-androstane-3a14-diol. Naunyn-

[16] Steyn PS, van Heerden FR. Bufadienolides of plant and animal origin. Natural Prod‐

[17] Mathews WR, DuCharme DW, Hamlyn JM, Harris DW, Mandel F, Clark MA, Lu‐ dens JH. Mass spectral characterization of an endogenous digitalislike factor from

[18] Hamlyn JM, Blaustein MP, Bova S, DuCharme DW, Harris DW, Mandel F, Mathews WR, Ludens JH. Identification and characterization of a ouabain-like compound from human plasma. Proceedings of the National Academy of Sciences of the United

[19] Schneider R, Antolovic R, Kost H, Sich B, Kirch U, Tepel M, Zidek W, Schoner W. Proscillaridin A immunoreactivity: its purification, transport in blood by a specific binding protein and its correlation with blood pressure. Clinical and Experimental

[20] Goto A, Yamada K, Ishii M, Sugimoto T. Digitalis-like activity in human plasma: re‐ lation to blood pressure and sodium balance. The American Journal of Medicine

[21] Bagrov AY, Fedorova OV, Dmitrieva RI, Howald WN, Hunter AP, Kuznetsova EA,

patients after acute myocardial infarction. Hypertension 1998;31 1097-1103.

, K+


Shpen VM. Characterization of a urinary bufodienolide Na+


/K

breast cancer cells. Archives of pharmacal research 2007;30 1216-1224.

tion. Cytotechnology 2010;62 573-83.

apeutic agents. Molecular Intervention 2008;8 36-49.

Schmiedeberg's Archives of Pharmacology 1985;329 414-426.

ture reviews. Drug discovery 2008;7 926-95.

human plasma. Hypertension 1991;17 930-935.

States of America 1991;88 6259-6263.

Hypertension 1998;20 593-599.

1990;89 420-426.

Hypotheses 1999;53 543-548.

78 Cancer Treatment - Conventional and Innovative Approaches

uct Reports 1998;15 397-413.

+

627-646.


[38] Elbaz HA, Stueckle TA, Wang HY, O'Doherty GA, Lowry DT, Sargent LM, Wang L, Dinu CZ, Rojanasakul Y. Digitoxin and a synthetic monosaccharide analog inhibit cell viability in lung cancer cells. Toxicology and Applied Pharmacology 2012;258 51-60.

cancer cells by up-regulation of death receptors 4 and 5. Cancer Research 2006;66

Anticancer Properties of Cardiac Glycosides http://dx.doi.org/10.5772/55381 81

[51] Chanvorachote P, Pongrakhananon V. Ouabain down-regulates Mcl-1 and sensitizes lung cancer cells to TRAIL-induced apoptosis. American Journal of Physiology-Cell

[52] Simon HU, Haj-Yehia A, Levi-Schaffer F. Role of reactive oxygen species (ROS) in

[53] Huang YT, Chueh SC, Teng CM, Guh JH. Investigation of ouabain-induced anticanc‐ er effect in human androgen-independent prostate cancer PC-3 cells. Biochemical

[54] Watabe M, Ito K, Masuda Y, Nakajo S, Nakaya K. Activation of AP-1 is required for bufalin-induced apoptosis in human leukemia U937cells. Oncogene 1998;16 779-787.

[55] Ameyar M, Wisniewska M, Weitzman JB. A role for AP-1 in apoptosis: the case for

[56] Okamoto K, Fujisawa K, Hasunuma T, Kobata T, Sumida T, Nishioka K. Selective ac‐ tivation of the JNK/AP-1 pathway in Fas-mediated apoptosis of rheumatoid arthritis

[57] Wang Z, Zheng M, Li Z, Li R, Jia L. Xiong X, Southall N, Wang S, Xia M, Austin CP, Zheng W, Xie Z, Sun Y. Cardiac glycosides inhibit p53 synthesis by a mechanism re‐

[58] Liu J, Tian J, Haas M, Shapiro JI, Askari A, Xie Z. Ouabain interaction with cardiac

and Ca2+ concentrations. Journal of Biological Chemistry 2000; 275 27838–27844.

[59] Newman RA, Yang P, Hittelman WN, Lu T, Ho DH, Ni D, Chan D, Vijjeswarapu M, Cartwright C, Dixon S, Felix E, Addington C. Oleandrin-mediated oxidative stress in human melanoma cells. Journal of Experimental Therapeutics & Oncology 2006;5

[60] Felth J, Rickardson L, Rosén J, Wickström M, Fryknäs M, Lindskog M, Bohlin L, Gull‐ bo J. Cytotoxic effects of cardiac glycosides in colon cancer cells, alone and in combi‐ nation with standard chemotherapeutic drugs. Journal of Natural Products 2009;72

[61] Kunta JR, Sinko PJ. Intestinal drug transporters: in vivo function and clinical impor‐

[62] Wang L, Raju U, Milas L, Molkentine D, Zhang Z, Yang P, Cohen L, Meng Z, Liao Z. Huachansu, containing cardiac glycosides, enhances radiosensitivity of human lung


lieved by Src or MAPK inhibition. Cancer Research 2009;69 6556-6564.

Physiology 2012; doi:10.1152/ajpcell.00225.2012.

apoptosis induction. Apoptosis 2000;5 415-418.

Pharmacology 2004;67 727-733.

and against. Biochimie 2003;85 747-52.

synoviocytes. Arthritis & Rheumatism 1997;40 919-926.

tance. Current Drug Metabolism 2004;5 109-24.

cancer cells. Anticancer Research 2011;31 2141-2148.

6867–5874.

Na+ /K+

167-181.

1969-1974.


cancer cells by up-regulation of death receptors 4 and 5. Cancer Research 2006;66 6867–5874.

[51] Chanvorachote P, Pongrakhananon V. Ouabain down-regulates Mcl-1 and sensitizes lung cancer cells to TRAIL-induced apoptosis. American Journal of Physiology-Cell Physiology 2012; doi:10.1152/ajpcell.00225.2012.

[38] Elbaz HA, Stueckle TA, Wang HY, O'Doherty GA, Lowry DT, Sargent LM, Wang L, Dinu CZ, Rojanasakul Y. Digitoxin and a synthetic monosaccharide analog inhibit cell viability in lung cancer cells. Toxicology and Applied Pharmacology 2012;258

[39] Tian J, Li X, Liang M, Liu L, Xie JX, Ye Q, Kometiani P, Tillekeratne M, Jin R, Xie Z. Changes in sodium pump expression dictate the effects of ouabain on cell growth.

[40] Yeh JY, Huang WJ, Kan SF, Wang PS. Inhibitory effects of digitalis on the prolifera‐ tion of androgen dependent and independent prostate cancercells. Journal of Urolo‐

[41] Winnicka K, Bielawski K, Bielawska A, Surazyński A. Antiproliferative activity of derivatives of ouabain, digoxin and proscillaridin A in human MCF-7 and MDA-MB-231 breast cancer cells. Biological and Pharmaceutical Bulletin 2008;31 1131-1140.

[42] Zhang H, Qian DZ, Tan YS, Lee K, Gao P, Ren YR, Rey S, Hammers H, Chang D, Pili R, Dang CV, Liu JO, Semenza GL. Digoxin and other cardiac glycosides inhibit HIF-1alpha synthesis and block tumor growth. Proceedings of the National Academy

[43] Sreenivasan Y, Sarkar A, Manna SK. Oleandrin suppresses activation of nuclear tran‐ scription factor-kB and activator protein-1 and potentiates apoptosis induced by ce‐

[44] Manna SK, Sah NK, Newman RA, Cisneros A, Aggarwal BB. Oleandrin suppresses activation of nuclear transcription factor-kappaB, activator protein-1, and c-Jun NH2

[45] Hashimoto S, Jing Y, Kawazoe N, Masuda Y, Nakajo S, Yoshida T, Kuroiwa Y, Na‐ kaya K. Bufain reduces the level of topoisomerase II in human leukemia cells and af‐

[46] Lavrik IN, Golks A, and Krammer PH. Caspases: pharmacological manipulation of

[47] Gan N, Chen G, Zhang W, Zhou J. Oleanen induces apoptosis of cervical cancer cells by up-regulation of Bim. International Journal of Gynecological Cancer 2012;22 38-42.

[48] Toillon RA, Descamps S, Adriaenssens E, Ricort JM, Bernard D, Boilly B, Le Bourhis X. Normal breast epithelial cells induce apoptosis of breast cancer cells via Fas sig‐

[49] Sreenivasan Y, Raghavendra PB, Manna SK. Oleandrin-mediated expression of Fas potentiates apoptosis in tumor cells. Journal of Clinical Immunology 2006;26 308-322.

[50] Frese S, Frese-Schaper M, Anne-Catherine A, Miescher D, Zumkehr B, Schmid RA. Cardiac glycosides initiate Apo2L/TRAIL induced apoptosis in non-small cell lung

fects the cytotoxicity of anticancer drugs. Leukemia Research 1997;21 875-883.

cell death. The Journal of Clinical Investigation 2005;115 2665-2672.

of Sciences of the United States of America 2008;105 19579-19586.

ramide. Biochemical Pharmacology 2003;66 2223–2239.

terminal kinase. Cancer Research 2000;60 3838-3847.

naling. Experimental Cell Research 2002;275 31-43.

Journal of Biological Chemistry 2009;284 14921-14929.

51-60.

gy 2001;166 1937-42.

80 Cancer Treatment - Conventional and Innovative Approaches


[63] Verheye-Dua FA, Böhm L. Na+ , K+ -ATPase inhibitor, ouabain accentuates irradiation damage in human tumour cell lines. Radiation Oncology Investigations 1998;6 109-119.

[75] Sakai H, Suzuki T, Maeda M, Takahashi Y, Horikawa N, Minamimura T, Tsukada K, Takeguchi N. Up-regulation of Na(+),K(+)-ATPase alpha 3-isoform and down-regula‐ tion of the alpha1-isoform in human colorectal cancer. FEBS Letters 2004;563 151-154.

Anticancer Properties of Cardiac Glycosides http://dx.doi.org/10.5772/55381 83

[76] Yang P, Menter DG, Cartwright C, Chan D, Dixon S, Suraokar M, Mendoza G, Llansa N, Newman RA. Oleandrin-mediated inhibition of human tumor cell proliferation: importance of Na,K-ATPase alpha subunits as drug targets. Molecular Cancer Thera‐

[77] Mijatovic T, Roland I, Van Quaquebek, Nilsson EB, Mathieu A, Van Vynckt F, Darro F, Blanco G, Facchini V, Kiss R. The α1 subunit of the sodium pump could represent a novel target to combat non-small cell lung cancers. Journal of Pathology 2007;212

[78] Lefranc F, Mijatovic T, Kondo Y, Sauvage S, Roland I, Debeir O, Krstic D, Vasic V, Gailly P, Kondo S, Blanco G, Kiss R. Targeting the á 1 subunit of the sodium pump to

[79] Boukerche H, Su ZZ, Kang DC, Fisher PB. Identification and cloning of genes dis‐ playing elevated expression as a consequence of metastatic progression in human

[80] Mathieu V, Pirker C, Vernier M, Mijatovic T, Berger W, Kiss R. New cardenolides, binders of the sodium pump, could represent interesting chemotherapeutical agents for melanoma treatment. American Association for Cancer Research (AACR) Annual

[81] Juncker T, Cerella C, Teiten MH, Morceau F, Schumacher M, Ghelfi J, Gaascht F, Schnekenburger M, Henry E, Dicato M, Diederich M. UNBS1450, a steroid cardiac glycoside inducing apoptotic cell death in humanleukemia cells. Biochemical Phar‐

[82] Juncker T, Schumacher M, Dicato M, Diederich M. UNBS1450 from Calotropis pro‐ cera as a regulator of signaling pathways involved in proliferation and cell death. Bi‐

[83] Elbaz HA, Stueckle TA, Tse W, Rojanasakul Y, Dinu CZ. Digitoxin and its analogs as novel cancer therapeutics. Experimental Hematology & Oncology 2012; 1 4.

melanoma cells by rapid subtraction hybridization. Gene 2004;343 191-201.

combat glioblastoma cells. Neurosurgery 2008;62 211-221.

Meeting, April 12-16, San Diego, USA; 2008.

ochemical Pharmacology 2009;78 1-10.

macology 2011;81 13-23.

peutics 2009;8 2319-2328.

170-179.


[75] Sakai H, Suzuki T, Maeda M, Takahashi Y, Horikawa N, Minamimura T, Tsukada K, Takeguchi N. Up-regulation of Na(+),K(+)-ATPase alpha 3-isoform and down-regula‐ tion of the alpha1-isoform in human colorectal cancer. FEBS Letters 2004;563 151-154.

[63] Verheye-Dua FA, Böhm L. Na+

82 Cancer Treatment - Conventional and Innovative Approaches

Research 1995;19 945-953.

Drugs 2000;11 455-63.

2000;20 51-91.

tics & Oncology. 2008;7 195-205.

cal Chemistry 1991;266 9327-9331.

109-119.

, K+

Strahlentherapie und Onkologie 1996;172 156-161.

regulation. Seminar in Nephrology 2005;25 292-303.

damage in human tumour cell lines. Radiation Oncology Investigations 1998;6

[64] Verheye-Dua FA, Böhm L. Influence of ouabain on cell inactivation by irradiation.

[65] Lawrence T.S. Ouabain sensitizes tumor cells but not normal cells to radiation. Inter‐ national Journal of Radiation Oncology, Biology, Physics 1998;15 953-958.

[66] Numazawa S, Honna Y, Yamamoto T, Yoshida T, Kuroiwa YA. cardiotonic steroid bufalin-like factor in human plasma induces leukemia cell differentiation. Leukemia

[67] Zhang L, Nakaya K, Yoshida T, Kuroiwa Y. Induction by bufalin of differentiation of human leukemia cells HL60, U937 and ML1 toward macrophage/monocyte-like cells and its potent synergistic effect on the differentiation of human leukemia cells in

[68] Pathak S, Multani AS, Narayan S, Kumar V, Newman RA. Anvirzel, an extract of Ne‐ rium oleander, induces cell death in human but not murine cancer cells. Anticancer

[69] Blanco G. Na,K-ATPase subunit heterogeneity as a mechanism for tissue-specifi c ion

[70] Mobasheri A, Avila J, Cózar-Castellano I, Brownleader MD, Trevan M, Francis MJ, Lamb JF, Martín-Vasallo P. Na/K-ATPase isozyme diversity; comparative biochemis‐ try and physiological implications of novel functional interactions. Bioscience Report

[71] Lin Y, Dubinsky WP, Ho DH, Felix E, Newman RA. Determinants of human and mouse melanoma cell sensitivities to oleandrin. Journal of Experimental Therapeu‐

[72] Lucchesi PA, Sweadner KJ. Postnatal changes in Na, K-ATPase isoforms expression in rat cardiac ventricle. conservation of biphasic ouabain affinity. Journal of Biologi‐

isozymes for cardioactive steroids, role of lactone ring, sugar moiety ad KCl concen‐

[74] O'Brien WJ, Lingrel JB, Wallick ET. Ouabain binding kinetics of the rat alpha two and alpha 3 isoforms of the sodium-potassium adenosine triphosphate. Archives of

[73] Noel F, Fagoo M, Godfraind T. A comparison of the affinities of rat (Na+

tration. Biochemical Pharmacology 1990;40 2611-2616.

Biochemistry and Biophysics 1994;310 32-39.

combination with other inducers. Cancer Research 1992;52 4634-4641.


,K+

)-ATPase


**Chapter 4**

**Liposomes as Carriers of Anticancer Drugs**

Diêgo dos Santos Ferreira, Elaine Amaral Leite and

Nanotechnology and nanoscience present a highly positive prospective of bringing benefits to many research areas and applications. Nanosized vehicles have received considerable attention over the past 30 years as pharmaceutical carriers with a wide range of applications, including drug delivery vehicles, adjuvants in vaccinations, signal enhancers/carriers in medical diagnostics and analytical biochemistry, solubilizers for various materials, as well as their role as a support matrix for chemical ingredients and as penetration enhancers in cosmetic products. More recent developments have reported on the field of liposomal drugs, from the viewpoint of clinically approved products, with cancer therapy representing the main area of interest [1-3]. In this context, liposomes can be used to improve current cancer treatment regimens due to their capacity to increase the solubility of poorly water-soluble antitumor drugs. Moreover, these also act to decrease the mononuclear phagocyte system's (MPS) uptake by using long-circulating liposomes which promote a passive directing toward the tumor region and can lead to an active directing toward the tumor site by connecting specific ligands to the liposome surface [4,5]. These strategies minimize drug degradation and inactivation upon administration, as well as increase the drug's bioavailability and the fraction of drug delivered within the pathological area, thus improving efficacy and/or minimizing drug

> © 2013 Lopes et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

distribution, and reproduction in any medium, provided the original work is properly cited.

and reproduction in any medium, provided the original work is properly cited.

Additional information is available at the end of the chapter

Sávia Caldeira de Araújo Lopes, Cristiane dos Santos Giuberti, Talita Guieiro Ribeiro Rocha,

Mônica Cristina Oliveira

http://dx.doi.org/10.5772/55290

**1. Introduction**

toxicity.

### **Liposomes as Carriers of Anticancer Drugs**

Sávia Caldeira de Araújo Lopes, Cristiane dos Santos Giuberti, Talita Guieiro Ribeiro Rocha, Diêgo dos Santos Ferreira, Elaine Amaral Leite and Mônica Cristina Oliveira

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/55290

### **1. Introduction**

Nanotechnology and nanoscience present a highly positive prospective of bringing benefits to many research areas and applications. Nanosized vehicles have received considerable attention over the past 30 years as pharmaceutical carriers with a wide range of applications, including drug delivery vehicles, adjuvants in vaccinations, signal enhancers/carriers in medical diagnostics and analytical biochemistry, solubilizers for various materials, as well as their role as a support matrix for chemical ingredients and as penetration enhancers in cosmetic products. More recent developments have reported on the field of liposomal drugs, from the viewpoint of clinically approved products, with cancer therapy representing the main area of interest [1-3]. In this context, liposomes can be used to improve current cancer treatment regimens due to their capacity to increase the solubility of poorly water-soluble antitumor drugs. Moreover, these also act to decrease the mononuclear phagocyte system's (MPS) uptake by using long-circulating liposomes which promote a passive directing toward the tumor region and can lead to an active directing toward the tumor site by connecting specific ligands to the liposome surface [4,5]. These strategies minimize drug degradation and inactivation upon administration, as well as increase the drug's bioavailability and the fraction of drug delivered within the pathological area, thus improving efficacy and/or minimizing drug toxicity.

© 2013 Lopes et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

### **2. Definition, structure, and classification of liposomes**

Liposomes are spherical vesicles composed of one or more lipid bilayers, involving an aqueous compartment (Figure 1). These are formed spontaneously when the lipids are dispersed in an aqueous medium by stirring, in turn giving rise to a population of vesicles which may reach a size range from dozens of nanometers to dozens of microns in diameter [6]. The lipid molecules possess head groups which are attracted to water molecules and organize them‐ selves in such a way as to point toward the aqueous cavity, whereas the hydrocarbon tails are repelled by the water molecules and point in the opposite direction.

either natural or synthetic origin, given that those of natural origin consist of a mixture of various lipids. In general, cylindrical molecular-shape lipids, such as phosphatidylcholine, phosphatidylserine, phosphatidylglycerol, and sphingomyelin, are chosen for liposome formulations, as they organize into stable bilayers in aqueous solutions. Among these lipids, phosphatidylcholines are the most widely used due to their appropriate stability and their ability to act against changes in pH or salt concentrations in the product or/and biological

O

R2

R3

**Table 1.** Examples of phospholipids used in liposome preparation.

O

O

Phospholipid (R1) Hydrophobic chains (R2,R3) (name) Lipid Name (Abbreviation)

**Phospholipid structural formula**

O

P

O R1

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 87

O

CH3(CH2)7CH=CH(CH2)7C(O)- (oleyl) Dioleylphosphatidylcholine (DOPC)

CH3(CH2)12C(O)- (myristoyl) Dimyristoylphosphatidylcholine (DMPC) CH3(CH2)14C(O)- (palmitoyl) Dipalmitoylphosphatidylcholine (DPPC) CH3(CH2)16C(O)- (stearoyl) Distearoylphosphatidylcholine (DSPC)

CH3(CH2)7CH=CH(CH2)7C(O)- (oleyl) Dioleoylphosphatidylethanolamine (DOPE) CH3(CH2)16C(O)- (stearoyl) Distearoylphosphatidylethanolamine (DSPE)

CH3(CH2)12C(O)- (myristoyl) Dimyristoylphosphatidylglycerol (DMPG) CH3(CH2)14C(O)- (palmitoyl) Dipalmitoylphosphatidylglycerol (DPPG)

CH3(CH2)14C(O)- (palmitoyl) Dipalmitoylphosphatidylserine (DPPS) CH3(CH2)16C(O)- (stearoyl) Distearoylphosphatidylserine (DSPS)

Liposomes are mainly classified in terms of size (small, intermediate, or large), number of bilayers (uni- and multi-lamellar), composition and mechanism of drug delivery. Small unilamellar vesicles (SUV) consist of a single lipid bilayer with an average diameter ranging

environment [10].

Phosphatidylcholine CH2CH2N+(CH3)3

Phosphatidylethanolamine

Phosphatidylglycerol CH2CHOHCH2OH

Phosphatidylserine CH2CHNH3 +COO-

CH2CH2NH3 <sup>+</sup>

The head groups of the inner layer point in the direction of the intravesicular fluid, with the tails pointing away from it. As such, the hydrocarbon tails of one layer point toward the hydrocarbon tails of the outer layer, in turn forming the normal bilipid membrane [3]. Once the liposomes have reached both the aqueous and lipid phases, they can encapsulate drugs with widely varying lipophilicities in the lipid bilayer, in the entrapped aqueous volume, or at the bilayer interface [7,8].

Reprinted from Regulatory Peptides, 138(2-3), Frezard F, Silva-Barcelos NM, Santos, RAS, A novel approach based on nanotechnology to investigate the chronic actions of short-lived peptides in specific sites of the brain, pages 59-65, Copyright (2007), with permission from Elsevier.

**Figure 1.** Basic structure and composition of liposomes. See [9].

Biodegradable and biocompatible phospholipids and sphingolipids are the lipids that are most commonly used to prepare liposomes (Table 1 and Figure 2). These structural lipids can be of either natural or synthetic origin, given that those of natural origin consist of a mixture of various lipids. In general, cylindrical molecular-shape lipids, such as phosphatidylcholine, phosphatidylserine, phosphatidylglycerol, and sphingomyelin, are chosen for liposome formulations, as they organize into stable bilayers in aqueous solutions. Among these lipids, phosphatidylcholines are the most widely used due to their appropriate stability and their ability to act against changes in pH or salt concentrations in the product or/and biological environment [10].

**2. Definition, structure, and classification of liposomes**

86 Cancer Treatment - Conventional and Innovative Approaches

repelled by the water molecules and point in the opposite direction.

at the bilayer interface [7,8].

Copyright (2007), with permission from Elsevier.

**Figure 1.** Basic structure and composition of liposomes. See [9].

Liposomes are spherical vesicles composed of one or more lipid bilayers, involving an aqueous compartment (Figure 1). These are formed spontaneously when the lipids are dispersed in an aqueous medium by stirring, in turn giving rise to a population of vesicles which may reach a size range from dozens of nanometers to dozens of microns in diameter [6]. The lipid molecules possess head groups which are attracted to water molecules and organize them‐ selves in such a way as to point toward the aqueous cavity, whereas the hydrocarbon tails are

The head groups of the inner layer point in the direction of the intravesicular fluid, with the tails pointing away from it. As such, the hydrocarbon tails of one layer point toward the hydrocarbon tails of the outer layer, in turn forming the normal bilipid membrane [3]. Once the liposomes have reached both the aqueous and lipid phases, they can encapsulate drugs with widely varying lipophilicities in the lipid bilayer, in the entrapped aqueous volume, or

Reprinted from Regulatory Peptides, 138(2-3), Frezard F, Silva-Barcelos NM, Santos, RAS, A novel approach based on nanotechnology to investigate the chronic actions of short-lived peptides in specific sites of the brain, pages 59-65,

Biodegradable and biocompatible phospholipids and sphingolipids are the lipids that are most commonly used to prepare liposomes (Table 1 and Figure 2). These structural lipids can be of

**Table 1.** Examples of phospholipids used in liposome preparation.

Liposomes are mainly classified in terms of size (small, intermediate, or large), number of bilayers (uni- and multi-lamellar), composition and mechanism of drug delivery. Small unilamellar vesicles (SUV) consist of a single lipid bilayer with an average diameter ranging

**Figure 2.** Chemical structures of some classes of sphingolipids. The length and saturation grade of the carbon chain can vary in each class of sphingolipid.

from 25 to 100 nm. Large unilamellar vesicles (LUV) also consist of one lipid bilayer and are greater than 100 nm, whereas multilamellar vesicles (MLV) are made up of several concentric lipid bilayers and measure of 1- 5 µm [7,11] (Figure 3). As regards the composition and mechanism of drug delivery, the liposomes can be classified as conventional liposomes, longcirculating liposomes, polymorphic liposomes (pH-sensitive, thermo-sensitive, and cationic liposomes), and decorated liposomes (surface-modified liposomes and immunoliposomes) (Figure 4).

rating purified glycolipids in the membranes of liposomes and testing their stability in mice. The results showed that the incorporation of monosialoganglioside GM1 and sphingomye‐ lin acted synergistically to diminish the rate and extent of uptake of liposomes by macrophag‐ es *in vivo*. However, monosialoganglioside GM1 did present some inconveniences, such as the expensive extraction process and the brain, as a prime source, which was considered unsuitable for use in pharmaceutical products. Klibanov and coworkers [14] were the first to show that the incorporation in the bilayer membrane of polyethylene glycol (PEG) lipid derivatives, significantly prolonged the circulation half-life of liposomes. It could be observed that the introduction of five to ten percent of PEG lipid-derivatives prevents opsonization through the induction of a fixed aqueous layer on the liposome surface, which shields surface charges, increases surface hydrophilicity, enhances repulsive interactions between polymercoated liposomes and blood components, and forms a polymeric layer which is impermea‐ ble for large opsonin molecules even at relatively low polymer concentrations [15-18]. This

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 89

**Figure 3.** Classification of liposomes according to average diameter and number of bilayers.

Conventional liposomes can possess different lipid compositions; however, the most commonly used lipids are phosphatidylcholines and cholesterol (CHOL). A major draw‐ back of conventional liposomes is their rapid uptake by MPS after systemic administration [8]. In the 1980s, the development of long-circulating liposomes boosted interest in the clinical application of liposomes as a drug delivery system for cancer treatment. Prior studies have shown that the presence of a dense glycocalyx with a high sialic acid content, used to produce a hydrophilic layer around the erythrocytes, prevented their destruction by MPS macrophag‐ es [12]. Allen and Chonn [13] applied this same concept to liposome development, incorpo‐

**Figure 3.** Classification of liposomes according to average diameter and number of bilayers.

from 25 to 100 nm. Large unilamellar vesicles (LUV) also consist of one lipid bilayer and are greater than 100 nm, whereas multilamellar vesicles (MLV) are made up of several concentric lipid bilayers and measure of 1- 5 µm [7,11] (Figure 3). As regards the composition and mechanism of drug delivery, the liposomes can be classified as conventional liposomes, longcirculating liposomes, polymorphic liposomes (pH-sensitive, thermo-sensitive, and cationic liposomes), and decorated liposomes (surface-modified liposomes and immunoliposomes)

**Figure 2.** Chemical structures of some classes of sphingolipids. The length and saturation grade of the carbon chain

Conventional liposomes can possess different lipid compositions; however, the most commonly used lipids are phosphatidylcholines and cholesterol (CHOL). A major draw‐ back of conventional liposomes is their rapid uptake by MPS after systemic administration [8]. In the 1980s, the development of long-circulating liposomes boosted interest in the clinical application of liposomes as a drug delivery system for cancer treatment. Prior studies have shown that the presence of a dense glycocalyx with a high sialic acid content, used to produce a hydrophilic layer around the erythrocytes, prevented their destruction by MPS macrophag‐ es [12]. Allen and Chonn [13] applied this same concept to liposome development, incorpo‐

(Figure 4).

can vary in each class of sphingolipid.

88 Cancer Treatment - Conventional and Innovative Approaches

rating purified glycolipids in the membranes of liposomes and testing their stability in mice. The results showed that the incorporation of monosialoganglioside GM1 and sphingomye‐ lin acted synergistically to diminish the rate and extent of uptake of liposomes by macrophag‐ es *in vivo*. However, monosialoganglioside GM1 did present some inconveniences, such as the expensive extraction process and the brain, as a prime source, which was considered unsuitable for use in pharmaceutical products. Klibanov and coworkers [14] were the first to show that the incorporation in the bilayer membrane of polyethylene glycol (PEG) lipid derivatives, significantly prolonged the circulation half-life of liposomes. It could be observed that the introduction of five to ten percent of PEG lipid-derivatives prevents opsonization through the induction of a fixed aqueous layer on the liposome surface, which shields surface charges, increases surface hydrophilicity, enhances repulsive interactions between polymercoated liposomes and blood components, and forms a polymeric layer which is impermea‐ ble for large opsonin molecules even at relatively low polymer concentrations [15-18]. This

problems, mainly due to the fact that these liposomes become reactive when submitted to membrane changes triggered by pH, variations in temperature, or surface charge alterations. A pH-sensitive liposome is generally stable at physiological pH but can undergo destabiliza‐ tion and acquires fusogenic properties under acidic conditions, thus leading to the release of its aqueous contents [19,20]. The development of this kind of liposome was proposed after the observation that some pathological tissues, including tumors or areas of inflammation and infection, as compared to normal tissues, reveal an acidic environment [21]. The endosome formed during the cellular internalization of liposomes also presents an acidic pH. The pH-sensitive liposomes consist mainly of phosphatidylethanolamine (PE) or its deriva‐ tives combined with amphiphilic compounds containing an acid group (e.g. carboxylic group) that acts as a stabilizer of the bilayer at neutral pH (Figure 5). The PE presents a conic geometry, since it contains a less bulky polar group, as compared to its hydrocarbon chain. This fact allows for strong intermolecular interaction between amine and phosphate groups in the polar moiety of PE. The molecules organize in a structure, called the inverted hexagonal phase, in which the polar head of the phospholipid points toward the inner cavity, while the carbon chains point toward the outer areas. The introduction of carboxylated compounds among phospholipid molecules promotes the repulsion of the phosphate groups with the carboxylate groups, which is deprotonated at neutral pH, favoring the formation of the bilayer (lamellar phase). The exposure of pH-sensitive liposomes to acidic pH leads to the protona‐ tion of carboxylate groups, removing the repulsion with phosphates, in turn destabilizing the bilayer and releasing the encapsulated substances [19, 22]. Hong and coworkers [23] showed that pH-sensitive liposomes made up of DOPE/distearoylphosphatidylglycerol (DSPG)/distearoylphosphatidylethanolaminepolyethyleneglycol2000 (DSPE-PEG2000), as compared to non-pH-sensitive liposomes made up of DPPC/CHOL/DSPE-PEG2000 are stable in plasma and are able to release an entrapped marker more rapidly within tumor tissues. Lipid molecules are able to organize at the lamellar phase, depending on the temperature, molecular shape of the lipids, and the conditions in the lipid-water mixture (concentration and ionic strength). Lamellar phases are classified in crystalline lamellar (LC), lamellar gel (Lβ), and lamellar liquid-crystalline (Lα). Lipid phase-transitions occur at certain tempera‐ tures according to the conditions of the medium. The main phase transition occurs at the temperature in which the lipid membrane passes from a tightly ordered gel (Lβ) to a fluid

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 91

lamellar (Lα), where the freedom of movement of individual molecules is high.

a bilayer composition in which the phase-transition temperature is slightly above 37o

Thermo-sensitive liposomes, another kind of polymorphic liposome, are vesicles that present

be seen in DPPC or lipids attached to thermosensitive copolymers (N-isopropylacrylamide and N-acryloylpyrrolidine). The local release of drugs entrapped in these liposomes is triggered by hyperthermia. Cationic liposomes present a positive surface charge, due to the presence of cationic lipids; can fuse with cell or endosome membranes; and are suitable for the delivery of negatively charged macromolecules (DNA, RNA, and oligonucleotides) [10].

In an attempt to improve the specificity of liposomes for injured organs or tissues and to prevent their uptake by the healthy tissues, liposomes with a functionalized surface, called *"decorated"* liposomes, have been developed by binding specific ligands. These ligands are

C, as can

**Figure 4.** Structural composition of different liposomes. Hydrophilic drugs (A) are incorporated in the inner aqueous phase of liposomes; lipophilic drugs (B) are incorporated in the liposome bilayer; amphifilic drugs (C) can be found in the interface lipid bilayer-inner aqueous phase. Conventional liposomes are exclusively made up of lipids. Long-circu‐ lating liposomes present a hydrophilic polymer attached to the liposome surface. The decorated liposomes can be subdivided as surface-modified liposomes (D) or immunoliposomes (E). Ligands can be directly attached to the lipo‐ some surface or to the extremity of a hydrophilic polymer. The cationic liposomes (F) are a type of polymorphic lipo‐ some used in the intracellular delivery of DNA.

discovery was a major breakthrough in liposome field research, supplying a safe synthetic compound that can be easily produced in mass scale.

Regardless of the strategies mentioned above, conventional and long-circulating liposomes may present a slow release of the active substance or may be unable to fuse with the endosome after internalization. As such, polymorphic liposomes have been developed to overcome these problems, mainly due to the fact that these liposomes become reactive when submitted to membrane changes triggered by pH, variations in temperature, or surface charge alterations.

A pH-sensitive liposome is generally stable at physiological pH but can undergo destabiliza‐ tion and acquires fusogenic properties under acidic conditions, thus leading to the release of its aqueous contents [19,20]. The development of this kind of liposome was proposed after the observation that some pathological tissues, including tumors or areas of inflammation and infection, as compared to normal tissues, reveal an acidic environment [21]. The endosome formed during the cellular internalization of liposomes also presents an acidic pH. The pH-sensitive liposomes consist mainly of phosphatidylethanolamine (PE) or its deriva‐ tives combined with amphiphilic compounds containing an acid group (e.g. carboxylic group) that acts as a stabilizer of the bilayer at neutral pH (Figure 5). The PE presents a conic geometry, since it contains a less bulky polar group, as compared to its hydrocarbon chain. This fact allows for strong intermolecular interaction between amine and phosphate groups in the polar moiety of PE. The molecules organize in a structure, called the inverted hexagonal phase, in which the polar head of the phospholipid points toward the inner cavity, while the carbon chains point toward the outer areas. The introduction of carboxylated compounds among phospholipid molecules promotes the repulsion of the phosphate groups with the carboxylate groups, which is deprotonated at neutral pH, favoring the formation of the bilayer (lamellar phase). The exposure of pH-sensitive liposomes to acidic pH leads to the protona‐ tion of carboxylate groups, removing the repulsion with phosphates, in turn destabilizing the bilayer and releasing the encapsulated substances [19, 22]. Hong and coworkers [23] showed that pH-sensitive liposomes made up of DOPE/distearoylphosphatidylglycerol (DSPG)/distearoylphosphatidylethanolaminepolyethyleneglycol2000 (DSPE-PEG2000), as compared to non-pH-sensitive liposomes made up of DPPC/CHOL/DSPE-PEG2000 are stable in plasma and are able to release an entrapped marker more rapidly within tumor tissues.

Lipid molecules are able to organize at the lamellar phase, depending on the temperature, molecular shape of the lipids, and the conditions in the lipid-water mixture (concentration and ionic strength). Lamellar phases are classified in crystalline lamellar (LC), lamellar gel (Lβ), and lamellar liquid-crystalline (Lα). Lipid phase-transitions occur at certain tempera‐ tures according to the conditions of the medium. The main phase transition occurs at the temperature in which the lipid membrane passes from a tightly ordered gel (Lβ) to a fluid lamellar (Lα), where the freedom of movement of individual molecules is high.

Thermo-sensitive liposomes, another kind of polymorphic liposome, are vesicles that present a bilayer composition in which the phase-transition temperature is slightly above 37o C, as can be seen in DPPC or lipids attached to thermosensitive copolymers (N-isopropylacrylamide and N-acryloylpyrrolidine). The local release of drugs entrapped in these liposomes is triggered by hyperthermia. Cationic liposomes present a positive surface charge, due to the presence of cationic lipids; can fuse with cell or endosome membranes; and are suitable for the delivery of negatively charged macromolecules (DNA, RNA, and oligonucleotides) [10].

discovery was a major breakthrough in liposome field research, supplying a safe synthetic

**Figure 4.** Structural composition of different liposomes. Hydrophilic drugs (A) are incorporated in the inner aqueous phase of liposomes; lipophilic drugs (B) are incorporated in the liposome bilayer; amphifilic drugs (C) can be found in the interface lipid bilayer-inner aqueous phase. Conventional liposomes are exclusively made up of lipids. Long-circu‐ lating liposomes present a hydrophilic polymer attached to the liposome surface. The decorated liposomes can be subdivided as surface-modified liposomes (D) or immunoliposomes (E). Ligands can be directly attached to the lipo‐ some surface or to the extremity of a hydrophilic polymer. The cationic liposomes (F) are a type of polymorphic lipo‐

Regardless of the strategies mentioned above, conventional and long-circulating liposomes may present a slow release of the active substance or may be unable to fuse with the endosome after internalization. As such, polymorphic liposomes have been developed to overcome these

compound that can be easily produced in mass scale.

some used in the intracellular delivery of DNA.

90 Cancer Treatment - Conventional and Innovative Approaches

In an attempt to improve the specificity of liposomes for injured organs or tissues and to prevent their uptake by the healthy tissues, liposomes with a functionalized surface, called *"decorated"* liposomes, have been developed by binding specific ligands. These ligands are

**Immunoliposomes**

CD20 Lymphomas and leukemias

HER2 Some types of breast cancer

HER2 Some types of breast cancer

anti-TfR scFv TfR Several types of tumor [30] **Surface modified liposomes with small molecules or peptides**

Transferrin TfR Several types of tumor [32]

mAb = monoclonal antibody; scFv = single chain variable fragment; RGD = Arginine-Glycine-Aspartic acid peptide; EGFR = Epidermal growth factor receptor; CD 19 = B-lymphocyte antigen CD19; CD 20 = B-lymphocyte antigen CD20; HER2 = Human epidermal growth factor receptor 2; MT1-MMP = membrane type-1 matrix metalloproteinase; TfR = Transferrin

Ligand Target Some types of cancer that overexpress the target (cell

Estrone ER Some types of breast cancer

**Table 2.** Some examples of ligands of "*decorated"* liposomes for active tumoral targeting

the target (cell lines)

Brain cancer (U-87)

EGFR Several types of tumor [26]

EGFR Several types of tumor [26]

MT1-MMP Several types of tumor [29]

lines)

Melanoma (A375 and B16)

Ovarian carcinoma

(B Cells) [27]

(B Cells) [27]

(BT-474 or MCF-7) [28]

(BT-474 or MCF-7) [28]

(BT-474 or MCF-7) [33]

(KB) [34]

References

93

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290

[25]

References

[31]

Ligand Target Some types of cancer that overexpress

mAb αCD19 CD19 Lymphomas and leukemias

Surface-bound nucleosomes

mAb 2C5

mAb C225 (Cetuximab)

scFv C10 (derived from mAb anti-human EGFR)

> mAb αCD20 (rituximab)

rhu-mAbHER2-Fab (Fab′ of trastuzumab)

scFv F5 (derived from mAb anti-human HER2)

222-1D8 (Fab' of mAb anti-human MT1- MMP)

RGD Integrins

Folate FR

receptor; ER = estrogen receptor; FR = Folate receptor.

Fab′

**Figure 5.** Main constituents of pH-sensitive liposomes and their structural representation (A) - DOPE and cholesteryl hemisuccinate (CHEMS); DOPE molecules alone will form the inverted hexagonal phase (B, upper). The introduction of CHEMS allows for the formation of the lamellar phase, which corresponds to the formation of liposomes (B, mid). When in contact with acidic pH, the liposomes undergo destabilization and return to the inverted hexagonal phase (B, low).

substances with a high affinity for receptors or other substances overexpressed by injured cells or tissues. These are also either absent or minimally present in healthy tissues [24] and are capable of directing the liposomes to the region of interest in a process called *active targeting*. The ligand can be introduced by covalent binding to the liposome surface or by electrostatic and hydrophobic insertion into the liposomal membrane [10]. Some examples of ligands are listed in Table 2.


mAb = monoclonal antibody; scFv = single chain variable fragment; RGD = Arginine-Glycine-Aspartic acid peptide; EGFR = Epidermal growth factor receptor; CD 19 = B-lymphocyte antigen CD19; CD 20 = B-lymphocyte antigen CD20; HER2 = Human epidermal growth factor receptor 2; MT1-MMP = membrane type-1 matrix metalloproteinase; TfR = Transferrin receptor; ER = estrogen receptor; FR = Folate receptor.

**Table 2.** Some examples of ligands of "*decorated"* liposomes for active tumoral targeting

substances with a high affinity for receptors or other substances overexpressed by injured cells or tissues. These are also either absent or minimally present in healthy tissues [24] and are capable of directing the liposomes to the region of interest in a process called *active targeting*. The ligand can be introduced by covalent binding to the liposome surface or by electrostatic and hydrophobic insertion into the liposomal membrane [10]. Some examples of ligands are

**Figure 5.** Main constituents of pH-sensitive liposomes and their structural representation (A) - DOPE and cholesteryl hemisuccinate (CHEMS); DOPE molecules alone will form the inverted hexagonal phase (B, upper). The introduction of CHEMS allows for the formation of the lamellar phase, which corresponds to the formation of liposomes (B, mid). When in contact with acidic pH, the liposomes undergo destabilization and return to the inverted hexagonal phase (B,

listed in Table 2.

92 Cancer Treatment - Conventional and Innovative Approaches

low).

### **3. Methods of liposome preparation**

As aforementioned, liposomes are spontaneously formed when phospholipids are hydrated. Additional steps are often necessary to modify the size distribution and lamellarity of lipo‐ somes. Liposome preparation involves three major steps: vesicle formation, vesicle size reduction, and purification. Several preparation methods have been established based on the scale of the production and other considerations, such as drug encapsulation efficiency, the drug's physicochemical characteristics, and the administration route (Table 3).

formation of MLV liposomes (Figure 6). This is the simplest method of vesicle formation;

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 95

**Figure 6.** Representation of liposome production by lipid hydration followed by vortex or manual stirring.

vesicle size reduction method (Table 3).

**4. Liposome characterization**

these parameters [6].

All methods based on the replacement of an organic solvent by an aqueous media show that the solvents, whether miscible or immiscible with water, are replaced by an aqueous solution. First, the water-immiscible organic solution containing lipids is injected into the aqueous phase (reverse-phase method), or the stepwise addition of the organic phase (specifically, ethanol) is injected into the aqueous phase (organic solvent injection method), followed by the removal of the solvent. These methods are able to form liposomes with a high encapsulation percentage of both hydrophilic and lipophilic substances. Generally, the incorporation of lipophilic drugs is performed through their codissolution with the lipids [37]. Hydrophilic drugs are dissolved in the aqueous medium, whereas amphiphilic drugs can be dissolved in both mediums. The processes of liposome preparation can result in the formation of large vesicles (MLV) with heterogeneous size distribution; therefore, it is important to calibrate the formulation using a

The behavior of liposomes in storage conditions and biological mediums is determined by specific factors, such as the size and surface charge of vesicles, chemical composition, mem‐ brane permeability, quantity of entrapped solutes, as well as the quality and purity of raw materials. Thus, it is of utmost importance to have as much information as possible regarding

however, it is limited in use due to its low encapsulation ability [36,37].


**Table 3.** Methods of liposomes preparation. For more details see [6, 11, 35].

The most commonly used methods for liposome preparation are lipid hydration and the replacement of organic solvents by an aqueous media (reverse-phase evaporation and organicsolvent injection). The lipid hydration followed by vortex or manual stirring, also known as Bangham's method, consists of dissolving the lipids in a suitable organic solvent, such as chloroform or methanol. This process is then followed by removing the solvent under reduced pressure, by rotary evaporation, until a thin film has been formed. After, the thin film is hydrated in an aqueous medium, above the phase-transition temperature, resulting in the formation of MLV liposomes (Figure 6). This is the simplest method of vesicle formation; however, it is limited in use due to its low encapsulation ability [36,37].

**Figure 6.** Representation of liposome production by lipid hydration followed by vortex or manual stirring.

All methods based on the replacement of an organic solvent by an aqueous media show that the solvents, whether miscible or immiscible with water, are replaced by an aqueous solution. First, the water-immiscible organic solution containing lipids is injected into the aqueous phase (reverse-phase method), or the stepwise addition of the organic phase (specifically, ethanol) is injected into the aqueous phase (organic solvent injection method), followed by the removal of the solvent. These methods are able to form liposomes with a high encapsulation percentage of both hydrophilic and lipophilic substances. Generally, the incorporation of lipophilic drugs is performed through their codissolution with the lipids [37]. Hydrophilic drugs are dissolved in the aqueous medium, whereas amphiphilic drugs can be dissolved in both mediums. The processes of liposome preparation can result in the formation of large vesicles (MLV) with heterogeneous size distribution; therefore, it is important to calibrate the formulation using a vesicle size reduction method (Table 3).

### **4. Liposome characterization**

**3. Methods of liposome preparation**

94 Cancer Treatment - Conventional and Innovative Approaches

**VESICLE SIZE REDUCTION**

**PURIFICATION**

As aforementioned, liposomes are spontaneously formed when phospholipids are hydrated. Additional steps are often necessary to modify the size distribution and lamellarity of lipo‐ somes. Liposome preparation involves three major steps: vesicle formation, vesicle size reduction, and purification. Several preparation methods have been established based on the scale of the production and other considerations, such as drug encapsulation efficiency, the

drug's physicochemical characteristics, and the administration route (Table 3).

**VESICLES FORMATION LIPOSOMES' TYPES**

Lipid hydration followed by vortex or manual stirring MLV Reverse-phase evaporation MLV, LUV Organic solvent injection MLV, LUV, SUV Freeze-thawing MLV, LUV pH gradient LUV, SUV Dehydration-rehydration MLV Detergent dialysis MLV, LUV

Extrusion through polycarbonate membranes LUV, SUV High-pressure homogenization LUV, SUV Microfluidization Mainly SUV Sonication Mainly SUV

Centrifugation - Dialysis - Column chromatography separation - Ultrafiltration -

**Table 3.** Methods of liposomes preparation. For more details see [6, 11, 35].

The most commonly used methods for liposome preparation are lipid hydration and the replacement of organic solvents by an aqueous media (reverse-phase evaporation and organicsolvent injection). The lipid hydration followed by vortex or manual stirring, also known as Bangham's method, consists of dissolving the lipids in a suitable organic solvent, such as chloroform or methanol. This process is then followed by removing the solvent under reduced pressure, by rotary evaporation, until a thin film has been formed. After, the thin film is hydrated in an aqueous medium, above the phase-transition temperature, resulting in the

The behavior of liposomes in storage conditions and biological mediums is determined by specific factors, such as the size and surface charge of vesicles, chemical composition, mem‐ brane permeability, quantity of entrapped solutes, as well as the quality and purity of raw materials. Thus, it is of utmost importance to have as much information as possible regarding these parameters [6].

Bilayer constituents are responsible for the shelf-life; interactions with biological components, such as specific tissues, cells, and proteins; as well as the kinetics of the release of the entrapped drug in liposomes. The size of the liposomes influences their *in vivo* distribution, as this factor can determine the amount of time that the liposomes will remain in the bloodstream before being removed. By contrast, the surface charge of vesicles influences their physical stability due to the possible occurrence of fusion and/or aggregation phenomena [6]. Therefore, detailed chemical, physical, and physicochemical characterizations are important in an attempt to ensure the efficacy and stabilization of the liposome formulation.

**CHARACTERISTICS METHODOLOGY**

Lysophospholipids quantification Liquid chromatography combined with Bartlett method

Lipid oxidation Spectroscopy, thin layer chromatography (TLC), high-performance liquid

Size Static and dynamic light scattering, microscopy techniques (light,

Surface charge Photon correlation spectroscopy associated with the electrophoretic

Lamellarity Nuclear magnetic resonance (31P-NMR), electron microscopy, small angle

Phase-transition temperature Differential scanning calorimetry and nuclear magnetic resonance (31P-

mobility

Lipid phase X-ray diffraction, differential scanning calorimetry

**Table 4.** Major methods of liposomes characterization. Based on [39, 40].

stored for extended periods [42,43]

X-ray scattering

NMR or 1H-NMR)

**5. Strategies to optimize liposome stability: Focus on freeze-drying**

As for any new high-tech product, the transfer from academic research to an industrial enterprise is crucial. Any commercial product involving a liposome formulation must contain well-defined stability characteristics and a shelf-life of more than one year. In this context, it is currently possible to obtain a reproducible preparation of large volumes of stable liposomes, and, in most cases, long-term stability problems have also been successfully solved [7].

The stability of liposomes is of major concern in their development for pharmaceutical applications. However, the potential application of liposomes as therapeutic tools is chal‐ lenged by their inherent physical and chemical instability in aqueous mediums, which can result in an increased bilayer permeability and subsequent drug leakage, vesicle aggregation/ fusion, and precipitation [41]. These instabilities can be stimulated by bilayer defects induced by chemical degradation (e.g. lipid oxidation and hydrolysis); by physical factors, such as heating or freezing; or due to phase transitions that occur when these aqueous dispersions are

The major approach to increase liposome stability is to establish an appropriate formulation, which requires the selection of the appropriate lipid composition and concentration, as well as the addition of other substances to improve its shelf-life. For example, the inclusion of cholesterol and its derivatives can reduce the permeability of the lipid bilayer. As unsaturated lipids commonly suffer peroxidation, the use of antioxidants and metal chelators may be necessary. Furthermore, it is of utmost importance to avoid the presence of oxygen both in the

electrochemical techniques and HPLC

fractionation and analytical centrifugation

chromatography (HPLC), gas-liquid chromatography (GC)

Spectrophotometry, fluorescence spectroscopy, enzyme-based methods,

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 97

electronic and atomic force), size-exclusion chromatography, field-flow

Phospholipids quantification Lipid phosphorus content (Bartlett method)

Determination of the encapsulation

percentage

Chemical analyses include the quantification of phospholipids and lysophospholipids, the evaluation of lipid oxidation, and the determination of the encapsulation percentage. As phospholipids represent the main constituents of the lipid bilayer, their quantification is important in evaluating the efficiency of the preparation method. Two degradation pathways have been described for phospholipids in aqueous liposomal dispersions: oxidative and hydrolytic degradation. The ester groups of the phospholipids can be hydrolyzed in the presence of water, producing lysophospholipids, a high concentration of which commonly leads to an increased permeability of the lipid bilayer and a destabilization of the system [38]. The oxidative pathway mainly involves phospholipids with unsaturated fatty acyl chains and tends to occur through the free radical mechanism. Lipid oxidation changes the bilayer's integrity, commonly resulting in drug leakage, in turn inducing aggregation and/or fusion phenomena. Another important chemical characterization is the encapsulation percentage, which is the ratio between the amount of drug already contained within the liposomes and the amount of drug added to the liposome at the beginning of the preparation. *In vivo* efficacy of the liposomes, as well as their physical and physicochemical properties, depends on the total amount of drug encapsulated within the liposome.

Physical characterization consists of determining the size, surface charge, and lamellarity of the liposomes. As the performance of liposomes *in vivo* and physical stability strongly depend on the vesicle size, liposome size distribution should be determined during the preparation process and storage. On the other hand, the nature and density of the charge on the liposome surface are important parameters that influence the mechanism and extent of liposome-cell interaction. Furthermore, the retention of the superficial charge for long periods during storage contributes to the high physical stability of the formulation.

Concerning the physicochemical characterization, the main evaluated parameters include the lipid phase and the phase-transition temperature. The determination of phase transitions and the fluidity of the bilayer are important in the production and application of liposomes, since the behavior of the liposome membrane determines the permeability, fusion/aggregation, and protein binding, thus influencing the stability of liposomes and their kinetics in biological systems.

The methods most commonly used for liposome characterization, according to the parameters described above, are listed in Table 4.


**Table 4.** Major methods of liposomes characterization. Based on [39, 40].

Bilayer constituents are responsible for the shelf-life; interactions with biological components, such as specific tissues, cells, and proteins; as well as the kinetics of the release of the entrapped drug in liposomes. The size of the liposomes influences their *in vivo* distribution, as this factor can determine the amount of time that the liposomes will remain in the bloodstream before being removed. By contrast, the surface charge of vesicles influences their physical stability due to the possible occurrence of fusion and/or aggregation phenomena [6]. Therefore, detailed chemical, physical, and physicochemical characterizations are important in an attempt to

Chemical analyses include the quantification of phospholipids and lysophospholipids, the evaluation of lipid oxidation, and the determination of the encapsulation percentage. As phospholipids represent the main constituents of the lipid bilayer, their quantification is important in evaluating the efficiency of the preparation method. Two degradation pathways have been described for phospholipids in aqueous liposomal dispersions: oxidative and hydrolytic degradation. The ester groups of the phospholipids can be hydrolyzed in the presence of water, producing lysophospholipids, a high concentration of which commonly leads to an increased permeability of the lipid bilayer and a destabilization of the system [38]. The oxidative pathway mainly involves phospholipids with unsaturated fatty acyl chains and tends to occur through the free radical mechanism. Lipid oxidation changes the bilayer's integrity, commonly resulting in drug leakage, in turn inducing aggregation and/or fusion phenomena. Another important chemical characterization is the encapsulation percentage, which is the ratio between the amount of drug already contained within the liposomes and the amount of drug added to the liposome at the beginning of the preparation. *In vivo* efficacy of the liposomes, as well as their physical and physicochemical properties, depends on the

Physical characterization consists of determining the size, surface charge, and lamellarity of the liposomes. As the performance of liposomes *in vivo* and physical stability strongly depend on the vesicle size, liposome size distribution should be determined during the preparation process and storage. On the other hand, the nature and density of the charge on the liposome surface are important parameters that influence the mechanism and extent of liposome-cell interaction. Furthermore, the retention of the superficial charge for long periods during storage

Concerning the physicochemical characterization, the main evaluated parameters include the lipid phase and the phase-transition temperature. The determination of phase transitions and the fluidity of the bilayer are important in the production and application of liposomes, since the behavior of the liposome membrane determines the permeability, fusion/aggregation, and protein binding, thus influencing the stability of liposomes and their kinetics in biological

The methods most commonly used for liposome characterization, according to the parameters

ensure the efficacy and stabilization of the liposome formulation.

96 Cancer Treatment - Conventional and Innovative Approaches

total amount of drug encapsulated within the liposome.

contributes to the high physical stability of the formulation.

systems.

described above, are listed in Table 4.

### **5. Strategies to optimize liposome stability: Focus on freeze-drying**

As for any new high-tech product, the transfer from academic research to an industrial enterprise is crucial. Any commercial product involving a liposome formulation must contain well-defined stability characteristics and a shelf-life of more than one year. In this context, it is currently possible to obtain a reproducible preparation of large volumes of stable liposomes, and, in most cases, long-term stability problems have also been successfully solved [7].

The stability of liposomes is of major concern in their development for pharmaceutical applications. However, the potential application of liposomes as therapeutic tools is chal‐ lenged by their inherent physical and chemical instability in aqueous mediums, which can result in an increased bilayer permeability and subsequent drug leakage, vesicle aggregation/ fusion, and precipitation [41]. These instabilities can be stimulated by bilayer defects induced by chemical degradation (e.g. lipid oxidation and hydrolysis); by physical factors, such as heating or freezing; or due to phase transitions that occur when these aqueous dispersions are stored for extended periods [42,43]

The major approach to increase liposome stability is to establish an appropriate formulation, which requires the selection of the appropriate lipid composition and concentration, as well as the addition of other substances to improve its shelf-life. For example, the inclusion of cholesterol and its derivatives can reduce the permeability of the lipid bilayer. As unsaturated lipids commonly suffer peroxidation, the use of antioxidants and metal chelators may be necessary. Furthermore, it is of utmost importance to avoid the presence of oxygen both in the form of dissolved oxygen and in the headspace of the container. Liposomes in an aqueous dispersion can also be hydrolyzed to form lysophospholipids and fatty acids. This process is catalyzed by hydroxyl and hydrogen ions and can be diminished by pH control, i.e., by adding a neutral buffer [44].

molecular volume of moderately large sugars will maintain the phospholipids molecules separate. A further reduction of the stress levels occurs when the sugars do not crystallize, but rather vitrify in the membrane space during drying. It has been proposed that the rigidity or mechanical resistance of the glassy solid makes it more difficult for the membranes to reduce

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 99

It should be noted that mechanisms of water replacement and vitrification are not mutually exclusive. The more important issue is the determining factor for Tm depression. According to the former hypothesis, it has been reported that vitrification is often required for the stabili‐ zation of the membrane but is not sufficient on its own [53]. Alternatively, it has also been proposed that specific sugar/lipid interaction may well exist but contributes little to the effect

In addition to stability, discussed above, other criteria must also be fulfilled to provide the acceptance of liposomes as pharmaceuticals. An efficient and adequate process for the preparation of sterile, pryrogen-free liposomes, by parenteral route, should be developed on an industrial scale. Furthermore, the final product must contain high and reproducible levels

To develop pharmaceutical products, preclinical studies of pharmacodynamic, pharmacoki‐ netic, and toxicological properties are required by regulatory agencies as part of procedures that must be followed prior to beginning clinical trials [54]. The Food and Drug Administration (FDA) requires that animal studies be reasonable predictors of the pharmacological activity of the investigated agent. In addition, toxicity studies should also be used to reveal adverse events

Pharmacodynamic studies include the characterization of action mechanisms, resistance, and treatment schedules, as well as the evaluation of the pharmacological activity *in vivo*. Although many drugs do act strongly against cancer, their use is commonly limited due to their toxic effects. Consequently, the definition of a toxicity profile is essential for the development of

Concerning antitumor therapy, the primary role of preclinical toxicology is to identify a safe starting dose for Phase I trials, in addition to a potential for toxicity and its reversibility. The evaluation of toxicity includes pharmacological safety studies; single and repeated dose toxicity studies; as well as genotoxicity/carcinogenicity, reproductive toxicity, and local tolerance studies. Furthermore, wherever possible, pharmacokinetic/toxicokinetic studies should be included to define pharmacological endpoints related to both toxicity and efficacy

Liposomes have been used as carriers of platinum compounds (cisplatin and oxaplatin), anthracyclines (doxorubicin and daunorubicin), paclitaxel, camptothecin derivatives, antime‐

their spatial distance under compressive stress [52].

of preventing an increase in Tm without the vitrification of sugars [48].

**6. Liposomes in cancer therapy: A review of pharmacodynamic,**

of drug entrapment, with minimal amounts of free drugs.

**pharmacokinetic, and toxicological studies**

that could be relevant to humans [55].

for their use in the design of Phase I trials [54].

new drugs.

Beyond formulation optimization, many methods available for the stabilization of liposomes have been investigated, such as freeze-drying and spray-drying. Freeze-drying is the main approach used to extend the shelf-life of liposomes, especially for thermosensitive drugs encapsulated within liposomes [43].

Freeze drying, also known as lyophilization, is a complex drying process employed to convert solutions of labile materials into solids of sufficient stability for distribution and storage. Freeze-drying is an industrial process which consists of removing the water from a frozen sample by sublimation and desorption through a vacuum process. Nevertheless, this process generates a wide range of stress, including fusion and drug loss, during the freezing and drying steps when conducted without the proper stabilizers [42,45]. To promote the stability of the vesicles during freeze-drying, cryoprotectants, such as saccharides and their derivates (e.g. sucrose, trehalose, hydroxypropyl-β-cyclodextrin (HP--CD), are employed [46,47].

It is generally accepted that sugars can depress the main phase transition temperature (Tm) from the lamellar gel (Lβ) to the lamellar liquid-crystalline (Lα) phase during drying. Two main hypotheses were proposed to explain this depression effect of sugars: water replacement and vitrification.

Water replacement is the earliest established and the most widely accepted mechanism of membrane stabilization by sugars. It has been proposed that specific and particular interac‐ tions between phospholipids and sugars are required to produce the protective effect. Water is generally found around the polar head groups, with a slight penetration within the ester region between the glycerol backbone and the fatty acid residues. Accordingly, studies have shown that the interactions occur through the hydrogen bond between hydroxyl groups of the sugars and the phosphate groups on the bilayer surface. In summary, the sugars reduce the interactions between the water and phospholipids, and then the water is replaced [43,48]. It could be observed that trehalose, which has been considered an anomalous sugar in some studies, can also penetrate deeply into the membrane and form hydrogen bonds with the carbonyl groups of the phospholipids [49,50,51]. Therefore, trehalose seems to have a higher affinity for bonding with phospholipids.

The vitrification hypothesis is based on the effect of the hydration's repulsive force, which separates the membrane phospholipids when there is an excess of water. During drying, when the water content, or the hydration repulse, is lowered, the compressive stress will increase. Vitrification states that sugars limit the close approach of phospholipids in the lamellar liquidcrystalline-to-lamellar gel phase transition through their nonspecific effects (no particular sugar-lipid interaction is required), namely, osmotic and volumetric properties as well as vitrification. The increase in the osmotic pressure of the solution, due to the presence of sugars, confines the water removal from the interface of the membranes. A high osmotic pressure leads to a low suction of any water molecules; therefore, less water is removed. Furthermore, the molecular volume of moderately large sugars will maintain the phospholipids molecules separate. A further reduction of the stress levels occurs when the sugars do not crystallize, but rather vitrify in the membrane space during drying. It has been proposed that the rigidity or mechanical resistance of the glassy solid makes it more difficult for the membranes to reduce their spatial distance under compressive stress [52].

form of dissolved oxygen and in the headspace of the container. Liposomes in an aqueous dispersion can also be hydrolyzed to form lysophospholipids and fatty acids. This process is catalyzed by hydroxyl and hydrogen ions and can be diminished by pH control, i.e., by adding

Beyond formulation optimization, many methods available for the stabilization of liposomes have been investigated, such as freeze-drying and spray-drying. Freeze-drying is the main approach used to extend the shelf-life of liposomes, especially for thermosensitive drugs

Freeze drying, also known as lyophilization, is a complex drying process employed to convert solutions of labile materials into solids of sufficient stability for distribution and storage. Freeze-drying is an industrial process which consists of removing the water from a frozen sample by sublimation and desorption through a vacuum process. Nevertheless, this process generates a wide range of stress, including fusion and drug loss, during the freezing and drying steps when conducted without the proper stabilizers [42,45]. To promote the stability of the vesicles during freeze-drying, cryoprotectants, such as saccharides and their derivates (e.g.

It is generally accepted that sugars can depress the main phase transition temperature (Tm) from the lamellar gel (Lβ) to the lamellar liquid-crystalline (Lα) phase during drying. Two main hypotheses were proposed to explain this depression effect of sugars: water replacement and

Water replacement is the earliest established and the most widely accepted mechanism of membrane stabilization by sugars. It has been proposed that specific and particular interac‐ tions between phospholipids and sugars are required to produce the protective effect. Water is generally found around the polar head groups, with a slight penetration within the ester region between the glycerol backbone and the fatty acid residues. Accordingly, studies have shown that the interactions occur through the hydrogen bond between hydroxyl groups of the sugars and the phosphate groups on the bilayer surface. In summary, the sugars reduce the interactions between the water and phospholipids, and then the water is replaced [43,48]. It could be observed that trehalose, which has been considered an anomalous sugar in some studies, can also penetrate deeply into the membrane and form hydrogen bonds with the carbonyl groups of the phospholipids [49,50,51]. Therefore, trehalose seems to have a higher

The vitrification hypothesis is based on the effect of the hydration's repulsive force, which separates the membrane phospholipids when there is an excess of water. During drying, when the water content, or the hydration repulse, is lowered, the compressive stress will increase. Vitrification states that sugars limit the close approach of phospholipids in the lamellar liquidcrystalline-to-lamellar gel phase transition through their nonspecific effects (no particular sugar-lipid interaction is required), namely, osmotic and volumetric properties as well as vitrification. The increase in the osmotic pressure of the solution, due to the presence of sugars, confines the water removal from the interface of the membranes. A high osmotic pressure leads to a low suction of any water molecules; therefore, less water is removed. Furthermore, the

sucrose, trehalose, hydroxypropyl-β-cyclodextrin (HP--CD), are employed [46,47].

a neutral buffer [44].

vitrification.

encapsulated within liposomes [43].

98 Cancer Treatment - Conventional and Innovative Approaches

affinity for bonding with phospholipids.

It should be noted that mechanisms of water replacement and vitrification are not mutually exclusive. The more important issue is the determining factor for Tm depression. According to the former hypothesis, it has been reported that vitrification is often required for the stabili‐ zation of the membrane but is not sufficient on its own [53]. Alternatively, it has also been proposed that specific sugar/lipid interaction may well exist but contributes little to the effect of preventing an increase in Tm without the vitrification of sugars [48].

In addition to stability, discussed above, other criteria must also be fulfilled to provide the acceptance of liposomes as pharmaceuticals. An efficient and adequate process for the preparation of sterile, pryrogen-free liposomes, by parenteral route, should be developed on an industrial scale. Furthermore, the final product must contain high and reproducible levels of drug entrapment, with minimal amounts of free drugs.

### **6. Liposomes in cancer therapy: A review of pharmacodynamic, pharmacokinetic, and toxicological studies**

To develop pharmaceutical products, preclinical studies of pharmacodynamic, pharmacoki‐ netic, and toxicological properties are required by regulatory agencies as part of procedures that must be followed prior to beginning clinical trials [54]. The Food and Drug Administration (FDA) requires that animal studies be reasonable predictors of the pharmacological activity of the investigated agent. In addition, toxicity studies should also be used to reveal adverse events that could be relevant to humans [55].

Pharmacodynamic studies include the characterization of action mechanisms, resistance, and treatment schedules, as well as the evaluation of the pharmacological activity *in vivo*. Although many drugs do act strongly against cancer, their use is commonly limited due to their toxic effects. Consequently, the definition of a toxicity profile is essential for the development of new drugs.

Concerning antitumor therapy, the primary role of preclinical toxicology is to identify a safe starting dose for Phase I trials, in addition to a potential for toxicity and its reversibility. The evaluation of toxicity includes pharmacological safety studies; single and repeated dose toxicity studies; as well as genotoxicity/carcinogenicity, reproductive toxicity, and local tolerance studies. Furthermore, wherever possible, pharmacokinetic/toxicokinetic studies should be included to define pharmacological endpoints related to both toxicity and efficacy for their use in the design of Phase I trials [54].

Liposomes have been used as carriers of platinum compounds (cisplatin and oxaplatin), anthracyclines (doxorubicin and daunorubicin), paclitaxel, camptothecin derivatives, antime‐ tabolites (methotrexate, cytarabine), and Vinca alkaloids (vincristine, vinblastine and vinorel‐ bine), aimed at reducing the toxic side-effects of cytostatic drugs without hampering their efficacy [56]. Their applications are based on the ability of liposomes to modify the tissue distribution of the entrapped drug, which becomes dependent on the physicochemical features of the liposomes and not the encapsulated content [57-59]. In addition, in cancer chemotherapy, the passive targeting of liposomes takes advantage of the inherent size of nanoparticles and the unique properties of tumor vasculature. As tumors grow and begin to outstrip the available supply of oxygen and nutrients, they release molecules that recruit new blood vessels to the tumor in a process called angiogenesis. Unlike the tight blood vessels in normal tissues, angiogenic blood vessels in tumor tissues contain gaps as large as 600 to 800 nm between adjacent endothelial cells. This dysregulated nature of tumor angiogenesis, coupled with poor lymphatic drainage, induces an enhanced permeability and a retention effect (EPR). Therefore, long-circulating liposomes will preferentially extravasate from these abnormal vessels and can selectively accumulate within the tumor interstitium [8,60-62].

lines derived from non-small cell lung cancer, renal cell carcinoma, and in normal hemato‐ poietic cell precursors. Lipoplatin®, when compared to CDDP, produced a stronger cytotoxic effect in both evaluated tumor cells lines and a lower toxicity in normal bone marrow stem cells [75]. Fielder and coworkers [76] investigated whether the cytotoxic effect of Lipoplatin® is dependent on the function integrity of DNA mismatch repair and concluded that this function is a key determining factor accounting for the cytotoxicity of lipoplatin. Antitumor efficacy of Lipoplatin® was assessed in xenografts of human breast, prostate, and pancreatic cancer, where a reduction in tumor size could be observed. Histopathological analyses of the tumors showed apoptosis in the tumor cells in a mechanism similar to that of CDDP [77]. Concerning toxicity, mice and rats treated with CDDP developed renal insufficiency with clear evidence of tubular damage, but those treated with the same dose of Lipoplatin® were completely free of kidney injury [78]. In addition, Lipoplatin® was safely administered to normal dogs at doses of up to 150 mg/m2 without the need for concurrent hydration protocols [79]. As regards clinical trials, Stathopoulos and coworkers [74] investigated the pharmacoki‐

malignant tumors. Measurement of platinum levels in the plasma of patients as a function of time showed that a maximum platinum level is attained at 6-8 h. The half-life of Lipoplatin® was 60-117 h, depending on the dose. Urine excretion reached approximately 40% of the infused dose in 3 days. Grades 1 and 2 gastrointestinal tract and hematological toxicities were detected after the administration of the highest dose. No nephrotoxicity could be observed. Boulikas and coworkers [80] explored the hypothesis that intravenous infusion of Lipopla‐ tin® can result in preferential tumor uptake in clinical trials. The determining of platinum levels in excised tumors and normal tissues showed that Lipoplatin® has the ability to preferentially concentrate on the malignant tissue (10-50 fold) of both primary and metastatic origin, as compared to adjacent normal tissue, following intravenous infusion in patients. Two phase I and I-II studies were carried out to investigate the maximum tolerated dose (MTD) as well as the dose-limiting toxicity (DLT). The first trial was conducted using a combination of Lipo‐ platin® and gemcitabine in patients with pretreated advanced pancreatic cancer, refractory to prior chemotherapy with gemcitabine. The results showed an absence of nephrotoxicity after

and grade 1 nausea/vomiting, fatigue, diarrhea, neurotoxicity, and thrombotic episodes could be observed after the administration of Lipoplatin® at similar doses. Thus, the DLT and MTD to Lipoplatin, established in combination with 1000 mg/m2 of gemcitabine, were 125 and 100

) in patients with pretreated advanced

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 101

. However, grade 2 neutropenia

netics and toxicity of Lipoplatin® (25-125 mg/m2

**Figure 7.** Chemical structure of CDDP

administration of Lipoplatin® at doses of 100 and 125 mg/m2

mg/m2

, respectively.

#### **6.1. Platinum compounds**

Cisplatin (CDDP) (Figure 7) is one of the most effective chemotherapeutic agents used by intravenous route in the treatment of ovary, lung, testicle, head, and neck carcinomas [63-69]. Furthermore, CDDP has been widely used in the treatment of peritoneal carcinomatosis by intraperitoneal route. However, the administration of CDDP by both routes is still hindered by toxicity, mainly nephrotoxicity. Conventional liposomes composed of phosphatidylcho‐ line/phosphatidylserine/CHOL containing CDDP were evaluated in IgM immunocytomabearing LOU/M rats. The results showed a lower incidence and severity of renal lesions after the liposomal formulation injection as compared to the free CDDP formulation. By contrast, the antitumor activity of this liposomal CDDP was similar to that of free CDDP, and the encapsulation of CDDP within this liposome formulation was unable to overcome drug resistance [70]. Newman and coworkers [71] developed a long-circulating formulation composed by hydrogenated soy phosphatidylcholine/DSPE-PEG2000/CHOL (SPI-077) and performed *in vivo* studies using both C26 colon carcinoma and the Lewis lung tumor model. SPI-077 exhibited a 55-fold lower distribution volume and a 60-fold larger plasma area under the concentration–time curve (AUC). An increased tumor platinum uptake and a significantly improved antitumor effect could be observed with the use of SPI-077, as compared to free CDDP [72]. The experience from several clinical trials (phase I/II) with SPI-077® indicated a promising toxicity profile; however, the therapeutic efficacy might be hampered by an unsatisfactory release of CDDP from the liposomes. In a phase I study performed with 27 adult patients, no antitumor efficacy after SPI-077® treatment, along with relatively low levels of platinum-DNA adducts in tumor samples, could be observed [73].

Another long-circulating liposomal formulation containing CDDP made up of soy phospha‐ tidylcholine (SPC)/ DPPG /CHOL/DSPE-PEG2000 is called Lipoplatin®. This formulation was developed to reduce the systemic toxicity of CDDP while simultaneously improving the targeting of the drug to the primary tumor and metastasis by enhancing the circulation time in body fluids and tissues [74]. Cytotoxicity studies of this formulation were performed in cell

**Figure 7.** Chemical structure of CDDP

tabolites (methotrexate, cytarabine), and Vinca alkaloids (vincristine, vinblastine and vinorel‐ bine), aimed at reducing the toxic side-effects of cytostatic drugs without hampering their efficacy [56]. Their applications are based on the ability of liposomes to modify the tissue distribution of the entrapped drug, which becomes dependent on the physicochemical features of the liposomes and not the encapsulated content [57-59]. In addition, in cancer chemotherapy, the passive targeting of liposomes takes advantage of the inherent size of nanoparticles and the unique properties of tumor vasculature. As tumors grow and begin to outstrip the available supply of oxygen and nutrients, they release molecules that recruit new blood vessels to the tumor in a process called angiogenesis. Unlike the tight blood vessels in normal tissues, angiogenic blood vessels in tumor tissues contain gaps as large as 600 to 800 nm between adjacent endothelial cells. This dysregulated nature of tumor angiogenesis, coupled with poor lymphatic drainage, induces an enhanced permeability and a retention effect (EPR). Therefore, long-circulating liposomes will preferentially extravasate from these abnormal vessels and can

Cisplatin (CDDP) (Figure 7) is one of the most effective chemotherapeutic agents used by intravenous route in the treatment of ovary, lung, testicle, head, and neck carcinomas [63-69]. Furthermore, CDDP has been widely used in the treatment of peritoneal carcinomatosis by intraperitoneal route. However, the administration of CDDP by both routes is still hindered by toxicity, mainly nephrotoxicity. Conventional liposomes composed of phosphatidylcho‐ line/phosphatidylserine/CHOL containing CDDP were evaluated in IgM immunocytomabearing LOU/M rats. The results showed a lower incidence and severity of renal lesions after the liposomal formulation injection as compared to the free CDDP formulation. By contrast, the antitumor activity of this liposomal CDDP was similar to that of free CDDP, and the encapsulation of CDDP within this liposome formulation was unable to overcome drug resistance [70]. Newman and coworkers [71] developed a long-circulating formulation composed by hydrogenated soy phosphatidylcholine/DSPE-PEG2000/CHOL (SPI-077) and performed *in vivo* studies using both C26 colon carcinoma and the Lewis lung tumor model. SPI-077 exhibited a 55-fold lower distribution volume and a 60-fold larger plasma area under the concentration–time curve (AUC). An increased tumor platinum uptake and a significantly improved antitumor effect could be observed with the use of SPI-077, as compared to free CDDP [72]. The experience from several clinical trials (phase I/II) with SPI-077® indicated a promising toxicity profile; however, the therapeutic efficacy might be hampered by an unsatisfactory release of CDDP from the liposomes. In a phase I study performed with 27 adult patients, no antitumor efficacy after SPI-077® treatment, along with relatively low levels of

Another long-circulating liposomal formulation containing CDDP made up of soy phospha‐ tidylcholine (SPC)/ DPPG /CHOL/DSPE-PEG2000 is called Lipoplatin®. This formulation was developed to reduce the systemic toxicity of CDDP while simultaneously improving the targeting of the drug to the primary tumor and metastasis by enhancing the circulation time in body fluids and tissues [74]. Cytotoxicity studies of this formulation were performed in cell

selectively accumulate within the tumor interstitium [8,60-62].

platinum-DNA adducts in tumor samples, could be observed [73].

**6.1. Platinum compounds**

100 Cancer Treatment - Conventional and Innovative Approaches

lines derived from non-small cell lung cancer, renal cell carcinoma, and in normal hemato‐ poietic cell precursors. Lipoplatin®, when compared to CDDP, produced a stronger cytotoxic effect in both evaluated tumor cells lines and a lower toxicity in normal bone marrow stem cells [75]. Fielder and coworkers [76] investigated whether the cytotoxic effect of Lipoplatin® is dependent on the function integrity of DNA mismatch repair and concluded that this function is a key determining factor accounting for the cytotoxicity of lipoplatin. Antitumor efficacy of Lipoplatin® was assessed in xenografts of human breast, prostate, and pancreatic cancer, where a reduction in tumor size could be observed. Histopathological analyses of the tumors showed apoptosis in the tumor cells in a mechanism similar to that of CDDP [77]. Concerning toxicity, mice and rats treated with CDDP developed renal insufficiency with clear evidence of tubular damage, but those treated with the same dose of Lipoplatin® were completely free of kidney injury [78]. In addition, Lipoplatin® was safely administered to normal dogs at doses of up to 150 mg/m2 without the need for concurrent hydration protocols [79]. As regards clinical trials, Stathopoulos and coworkers [74] investigated the pharmacoki‐ netics and toxicity of Lipoplatin® (25-125 mg/m2 ) in patients with pretreated advanced malignant tumors. Measurement of platinum levels in the plasma of patients as a function of time showed that a maximum platinum level is attained at 6-8 h. The half-life of Lipoplatin® was 60-117 h, depending on the dose. Urine excretion reached approximately 40% of the infused dose in 3 days. Grades 1 and 2 gastrointestinal tract and hematological toxicities were detected after the administration of the highest dose. No nephrotoxicity could be observed. Boulikas and coworkers [80] explored the hypothesis that intravenous infusion of Lipopla‐ tin® can result in preferential tumor uptake in clinical trials. The determining of platinum levels in excised tumors and normal tissues showed that Lipoplatin® has the ability to preferentially concentrate on the malignant tissue (10-50 fold) of both primary and metastatic origin, as compared to adjacent normal tissue, following intravenous infusion in patients. Two phase I and I-II studies were carried out to investigate the maximum tolerated dose (MTD) as well as the dose-limiting toxicity (DLT). The first trial was conducted using a combination of Lipo‐ platin® and gemcitabine in patients with pretreated advanced pancreatic cancer, refractory to prior chemotherapy with gemcitabine. The results showed an absence of nephrotoxicity after administration of Lipoplatin® at doses of 100 and 125 mg/m2 . However, grade 2 neutropenia and grade 1 nausea/vomiting, fatigue, diarrhea, neurotoxicity, and thrombotic episodes could be observed after the administration of Lipoplatin® at similar doses. Thus, the DLT and MTD to Lipoplatin, established in combination with 1000 mg/m2 of gemcitabine, were 125 and 100 mg/m2 , respectively.

The combination achieved a partial response in 8.33% of the patients, disease stability in 58.3%, and clinical benefit in 33.3% [81]. In the second study, similar DLT and MTD were defined in patients with refractory or resistant non-small cell lung carcinoma [82]. However, as lipoplatin was combined with gemcitabine, the latter can be responsible for the toxicity observed. In this context, the administration of single Lipoplatin® was also tested and nephrotoxicity, gastro‐ intestinal toxicity, and myelotoxicity were investigated as the main adverse reactions. From this study, DLT and MTD values were found for Lipoplatin® at 350 mg/m2 and 300 mg/m2 , respectively. The dose of 350 mg/m2 was not accompanied by nephrotoxicity, only by gastro‐ intestinal side effects and grade 1-2 myelotoxicity. It seems that the dose of Lipoplatin® can reach a level that is double or even higher than that of CDDP without increasing toxicity [83]. A phase II study combining Lipoplatin® and vinorelbine in the first-line treatment of HER2/ neu-negative metastatic breast cancer was also conducted [84]. The results showed complete response in 9.4% of the patients, partial response in 43.8%, stable disease in 37.5%, and progressive disease in 9.4%. In addition, this regimen was well tolerated and no grade 3/4 nephrotoxicity and neurotoxicity could be detected. In another phase II trial, Lipoplatin® (120 mg/m2 given on days 1, 8, 15), administered in association with gemcitabine (1000 mg/m2 given on days 1, 8) in inoperable (stage IIIB/IV) non-small cell lung cancer, showed a better response rate (31.7%) than those treated with CDDP associated with gemcitabine (25.6%). Furthermore, lower nephrotoxicity after Lipoplatin® treatment, as compared to CDDP treatment, could be observed [85]. The first phase III clinical trial reported is a randomized, multicenter safety and efficacy study in patients with advanced squamous cell carcinoma of the head and neck. The pharmacokinetic profile of Lipoplatin® in combination with 5-fluorouracil showed that the liposomal formulation has a greater body clearance and a shorter half-life than does free CDDP, which confirms the clinical observation of decreased toxicity, especially nephrotoxicity [86]. The efficacy results showed 38.8% and 19% objective partial remission after treatment with free CDDP and lipoplatin, respectively. On the other hand, 64% of the patients achieved a stable disease after Lipoplatin® treatment, as compared to 50% of the patients that received CDDP [87]. In a second phase III trial, Lipoplatin® was much more well-tolerated than was CDDP in non-small cell lung cancer. Chemotherapy-naive patients received either 200 mg/m2 of liposomal CDDP and 135 mg/m2 paclitaxel (arm A) or 75 mg/m2 of liposomal CDDP and 135 mg/m2 of paclitaxel (arm B), once every 2 weeks. Arm A patients showed statistically significant lower nephrotoxicity, grade 3 and 4 leucopenia, grade 2 and 3 neuropathy, nausea, vomiting, and fatigue. There was no significant difference in the median and overall survival and in time to tumor progression (TTP) between the two arms; the median survival was 9 and 10 months in arms A and B, respectively, while TTP was 6.5 and 6 months in arms A and B, respectively [88]. Therefore, phase I, II, and III trials have shown that Lipoplatin® presents similar antitumor efficacy to CDDP in pancreatic, head and neck, breast cancers, and non-small cell lung carcinoma, as well as reduced toxicity, mainly nephrotoxicity. Preliminary studies have shown that Lipoplatin® is a candidate to be used in patients with renal failure [89].

bearing mice treated with CDDP-SLX-Lip showed a survival rate of 75% at 14 days, even when a lethal level of CDDP was injected. Loss of body weight was negligible, and no histological abnormality could be found in many of the normal tissues. Accumulation of CDDP-SLX-Lip was approximately 6 times more than that of CDDP-Lip or CDDP. Therefore, a better antitu‐ mor activity could be observed for CDDP-SLX-Lip than for CDDP-Lip, with significantly less

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 103

Although CDDP is one of the most widely used chemotherapeutic agents, the development of tumor cell resistance against CDDP is a limitation in the clinical application of this drug. In this context, Krieger and coworkers [69] performed *in vitro* studies which demonstrated that liposomes have the potential to overcome the chemoresistance of tumor cells. The lipid composition of liposomes contained SPC/CHOL/distearoylphosphatidylethanolaminepolye‐ thyleneglycol (DSPE-PEG) in a 65/30/5 molar ratio, respectively. In these studies, PEGylated CDDP-containing liposomes were prepared, and the targetability of transferrin receptors (TfR) to correlate CDDP cell uptake with cytotoxicity in sensitive and CDDP resistant ovarian cancer cells (A2780), as compared to the free drug, was analyzed. Cytotoxicity proved to be even higher for liposomes, as compared to free CDDP, in the resistant cells after 24, 48, and 72 h,

Júnior and coworkers [90] developed long-circulating and pH-sensitive liposomes containing CDDP (SpHL-CDDP), which were made up of DOPE/CHEMS/DSPE-PEG2000 at a molar ratio of 5.7:3.8:0.5, respectively. In an acid medium, such as tumor sites, CHEMS molecules undergo protonation, followed by the destabilization of liposomes and the release of CDDP. Thus, it is expected that the released CDDP in this specific site can improve the antitumor effect and reduce, or even eliminate, the side effects. Studies were carried out concerning the stability, cytotoxicity, and accumulation of this new formulation in a human small-cell lung carcinoma cell line (GLC4), as well as in its resistant subline. These liposomes were stable in plasma, circumvented the preclinical resistance to treatment with CDDP, and were able to introduce the same level of CDDP within resistant and sensitive cells. Biodistribution studies have demonstrated the ability of SpHL-CDDP, as compared to the injection of free CDDP, to promote a higher concentration and affinity of CDDP in Ehrlich solid tumors, as well as a lower renal perfusion of the anticancer agent after intravenous administration [90]. CDDP has also been widely used in the treatment of peritoneal carcinomatosis by the intraperitoneal (i.p.) route. However, CDDP, a low-molecular-weight compound, is rapidly absorbed by the capillaries in the i.p. serosa and transferred to the bloodstream, inducing the appearance of systemic side-effects, such as nephrotoxicity. Furthermore, i.p. CDDP chemotherapy is limited to patients whose residual tumor nodules are less than 0.5 cm in diameter after surgical debulking [91]. The failure of i.p. therapy is attributed to the poor penetration of CDDP within larger tumor masses. To achieve an optimal drug penetration within the tumor, the use of a high concentration and a longer time of contact with the tumor are required. In this context, Araújo and coworkers [92] evaluated the tissue distribution of SpHL-CDDP after their i.p. administration in Ehrlich ascitic tumor-bearing mice. The CDDP AUC obtained for ascitic fluid and blood after SpHL-CDDP administration was 3.3-fold larger and 1.3-fold lower, respec‐

toxic effects in normal tissues.

and slightly lower in the sensitive cells.

Hirai and coworkers [68] encapsulated CDDP into liposomes and further conjugated the CDDP liposomes (CDDP-Lip) with a tetrasaccharide carbohydrate, Sialyl LewisX (CDDP-SLX-Lip). These liposomes consisted of DPPC/CHOL/ganglioside/dicetylphosphate/dipalmitoyl‐ phosphatidylethanolamine (DPPE) at the molar ratio of 35:40:5:15:5, respectively. A549 tumorbearing mice treated with CDDP-SLX-Lip showed a survival rate of 75% at 14 days, even when a lethal level of CDDP was injected. Loss of body weight was negligible, and no histological abnormality could be found in many of the normal tissues. Accumulation of CDDP-SLX-Lip was approximately 6 times more than that of CDDP-Lip or CDDP. Therefore, a better antitu‐ mor activity could be observed for CDDP-SLX-Lip than for CDDP-Lip, with significantly less toxic effects in normal tissues.

The combination achieved a partial response in 8.33% of the patients, disease stability in 58.3%, and clinical benefit in 33.3% [81]. In the second study, similar DLT and MTD were defined in patients with refractory or resistant non-small cell lung carcinoma [82]. However, as lipoplatin was combined with gemcitabine, the latter can be responsible for the toxicity observed. In this context, the administration of single Lipoplatin® was also tested and nephrotoxicity, gastro‐ intestinal toxicity, and myelotoxicity were investigated as the main adverse reactions. From this study, DLT and MTD values were found for Lipoplatin® at 350 mg/m2 and 300 mg/m2

intestinal side effects and grade 1-2 myelotoxicity. It seems that the dose of Lipoplatin® can reach a level that is double or even higher than that of CDDP without increasing toxicity [83]. A phase II study combining Lipoplatin® and vinorelbine in the first-line treatment of HER2/ neu-negative metastatic breast cancer was also conducted [84]. The results showed complete response in 9.4% of the patients, partial response in 43.8%, stable disease in 37.5%, and progressive disease in 9.4%. In addition, this regimen was well tolerated and no grade 3/4 nephrotoxicity and neurotoxicity could be detected. In another phase II trial, Lipoplatin® (120

 given on days 1, 8, 15), administered in association with gemcitabine (1000 mg/m2 given on days 1, 8) in inoperable (stage IIIB/IV) non-small cell lung cancer, showed a better response rate (31.7%) than those treated with CDDP associated with gemcitabine (25.6%). Furthermore, lower nephrotoxicity after Lipoplatin® treatment, as compared to CDDP treatment, could be observed [85]. The first phase III clinical trial reported is a randomized, multicenter safety and efficacy study in patients with advanced squamous cell carcinoma of the head and neck. The pharmacokinetic profile of Lipoplatin® in combination with 5-fluorouracil showed that the liposomal formulation has a greater body clearance and a shorter half-life than does free CDDP, which confirms the clinical observation of decreased toxicity, especially nephrotoxicity [86]. The efficacy results showed 38.8% and 19% objective partial remission after treatment with free CDDP and lipoplatin, respectively. On the other hand, 64% of the patients achieved a stable disease after Lipoplatin® treatment, as compared to 50% of the patients that received CDDP [87]. In a second phase III trial, Lipoplatin® was much more well-tolerated than was CDDP in non-small cell lung cancer. Chemotherapy-naive patients received either 200 mg/m2 of liposomal CDDP and 135 mg/m2 paclitaxel (arm A) or 75 mg/m2 of liposomal CDDP and 135 mg/m2 of paclitaxel (arm B), once every 2 weeks. Arm A patients showed statistically significant lower nephrotoxicity, grade 3 and 4 leucopenia, grade 2 and 3 neuropathy, nausea, vomiting, and fatigue. There was no significant difference in the median and overall survival and in time to tumor progression (TTP) between the two arms; the median survival was 9 and 10 months in arms A and B, respectively, while TTP was 6.5 and 6 months in arms A and B, respectively [88]. Therefore, phase I, II, and III trials have shown that Lipoplatin® presents similar antitumor efficacy to CDDP in pancreatic, head and neck, breast cancers, and non-small cell lung carcinoma, as well as reduced toxicity, mainly nephrotoxicity. Preliminary studies have shown that Lipoplatin® is a candidate to be used in patients with renal failure [89].

Hirai and coworkers [68] encapsulated CDDP into liposomes and further conjugated the CDDP liposomes (CDDP-Lip) with a tetrasaccharide carbohydrate, Sialyl LewisX (CDDP-SLX-Lip). These liposomes consisted of DPPC/CHOL/ganglioside/dicetylphosphate/dipalmitoyl‐ phosphatidylethanolamine (DPPE) at the molar ratio of 35:40:5:15:5, respectively. A549 tumor-

was not accompanied by nephrotoxicity, only by gastro‐

respectively. The dose of 350 mg/m2

102 Cancer Treatment - Conventional and Innovative Approaches

mg/m2

,

Although CDDP is one of the most widely used chemotherapeutic agents, the development of tumor cell resistance against CDDP is a limitation in the clinical application of this drug. In this context, Krieger and coworkers [69] performed *in vitro* studies which demonstrated that liposomes have the potential to overcome the chemoresistance of tumor cells. The lipid composition of liposomes contained SPC/CHOL/distearoylphosphatidylethanolaminepolye‐ thyleneglycol (DSPE-PEG) in a 65/30/5 molar ratio, respectively. In these studies, PEGylated CDDP-containing liposomes were prepared, and the targetability of transferrin receptors (TfR) to correlate CDDP cell uptake with cytotoxicity in sensitive and CDDP resistant ovarian cancer cells (A2780), as compared to the free drug, was analyzed. Cytotoxicity proved to be even higher for liposomes, as compared to free CDDP, in the resistant cells after 24, 48, and 72 h, and slightly lower in the sensitive cells.

Júnior and coworkers [90] developed long-circulating and pH-sensitive liposomes containing CDDP (SpHL-CDDP), which were made up of DOPE/CHEMS/DSPE-PEG2000 at a molar ratio of 5.7:3.8:0.5, respectively. In an acid medium, such as tumor sites, CHEMS molecules undergo protonation, followed by the destabilization of liposomes and the release of CDDP. Thus, it is expected that the released CDDP in this specific site can improve the antitumor effect and reduce, or even eliminate, the side effects. Studies were carried out concerning the stability, cytotoxicity, and accumulation of this new formulation in a human small-cell lung carcinoma cell line (GLC4), as well as in its resistant subline. These liposomes were stable in plasma, circumvented the preclinical resistance to treatment with CDDP, and were able to introduce the same level of CDDP within resistant and sensitive cells. Biodistribution studies have demonstrated the ability of SpHL-CDDP, as compared to the injection of free CDDP, to promote a higher concentration and affinity of CDDP in Ehrlich solid tumors, as well as a lower renal perfusion of the anticancer agent after intravenous administration [90]. CDDP has also been widely used in the treatment of peritoneal carcinomatosis by the intraperitoneal (i.p.) route. However, CDDP, a low-molecular-weight compound, is rapidly absorbed by the capillaries in the i.p. serosa and transferred to the bloodstream, inducing the appearance of systemic side-effects, such as nephrotoxicity. Furthermore, i.p. CDDP chemotherapy is limited to patients whose residual tumor nodules are less than 0.5 cm in diameter after surgical debulking [91]. The failure of i.p. therapy is attributed to the poor penetration of CDDP within larger tumor masses. To achieve an optimal drug penetration within the tumor, the use of a high concentration and a longer time of contact with the tumor are required. In this context, Araújo and coworkers [92] evaluated the tissue distribution of SpHL-CDDP after their i.p. administration in Ehrlich ascitic tumor-bearing mice. The CDDP AUC obtained for ascitic fluid and blood after SpHL-CDDP administration was 3.3-fold larger and 1.3-fold lower, respec‐ tively, when compared with free CDDP treatment, thus indicating its high retention within the peritoneal cavity.

In addition, MTD values obtained after i.v. and i.p. administration of SpHL-CDDP in healthy mice were approximately three times higher than those obtained using free CDDP. Hemato‐ logical investigations revealed no alterations in red and white blood cell counts upon i.v. and i.p. administration of SpHL-CDDP at a dose corresponding to the MTD in mice. In addition, SpHL-CDDP treatment caused no pronounced alterations in the blood urea and creatinine levels, nor did it induce morphological alterations in the kidneys of the mice [93, 94]. These findings indicate that the use of SpHL-CDDP as a drug delivery system can increase the safety of the drug and improve the therapeutic efficacy of the CDDP-based treatment. Thus, antitu‐ mor activity studies were conducted, and the results showed a significant reduction in the tumor volume, a higher tumor growth inhibition ratio, and the complete remission of the tumor in 18.2% of the Ehrlich solid tumor-bearing mice treated with SpHL-CDDP by intrave‐ nous route, as compared to the free CDDP treatment [94, 95]. In addition, the survival of animals treated with SpH-CDDP was higher than those treated with free CDDP after i.p. administration in initial or disseminated Ehrlich ascitic tumor-bearing mice [96]. These findings strongly indicate the potential of SpHL-CDDP for future clinical studies.

tinal tract toxicity. These preliminary results showed adequate effectiveness in pretreated

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 105

The anthracyclines, represented by doxorubicin, daunorubicin, and their derivatives (Figure 9), are widely used in the treatment of several hematological and solid tumors and are considered to be a first-line therapy for advanced breast cancer [100]. Although conventional anthracyclines have been extensively used for the treatment of a variety of cancers, they can be associated with the development of substantial cardiotoxicity, which is both cumulative and irreversible. Furthermore, cardiotoxicity can be increased nearly four-fold when these drugs are administered in association with other chemotherapeutic drugs [101]. In this case, the preclinical and clinical studies have focused on the development of liposomal formulations, aimed at decreasing the acute and cumulative cardiotoxicity, in addition to attenuating other

Forssen and coworkers [103] reported the ability of liposomes containing daunorubicin (DNR), made up of DSPC/CHOL, to accumulate within the P-1798 murine lymphosarcoma and MA16C mammary adenocarcinona tumor model. The maximum levels of liposome uptake exceeded those achieved by the free drug between 2.5 and 20-fold, which was translated into a 10-fold increase in AUC of tumor exposure to DNR in the P-1798 system. Other investigations also significantly demonstrated increased efficacy and decreased toxicity of liposomes

drug-related events (e.g. bone marrow depression, alopecia, and nausea) [102].

patients [98,99].

**Figure 8.** Chemical structure of oxaliplatin.

**Figure 9.** Chemical structures of principal anthracyclines.

**6.2. Anthracyclines**

Oxaliplatin (Figure 8), an analoge of CDDP, has shown a good *in vitro* and *in vivo* antitumor effect and a better safety profile than cisplatin. However, the use of oxaliplatin is associated with side-effects which include neurotoxicity, hematologic toxicity and gastrointestinal tract toxicity. In addition, there is a significant risk of grade 3/4 neutropenia to the patients, and the occurrence of nausea and vomiting were generally mild to moderate. Nephrotoxicity is mild, allowing for the administration of oxaliplatin without hydration. Often, severe side effects can be observed, such as tubular necrosis. Furthermore, cellular resistance to free oxaliplatin has been observed, preventing the potential efficacy of free oxaliplatin [97]. Lipoxal® is a liposomal formulation of oxaliplatin made up of hydrogenated soy phospahatidylcholine (HSPC)/DPPG/ CHOL/DSPE-PEG. This liposomal formulation containing oxaliplatin has also proven to induce the complete disappearance of human breast cancers in mice after 6 intravenous injections with 4 days intervals at a dose of 16 mg/Kg. On the other hand, the free oxaliplatin at its MTD could only cause shrinkage, not the disappearance of tumors. To estimate the adverse reactions and detect the dose limiting toxicity (DLT), as well as the MTD of Lipoxal®, a Phase I clinical study was conducted. Twenty-seven patients with advanced disease of the gastrointestinal system (stage IV gastrointestinal cancers, including colorectal, gastric, and pancreatic), who had failed previous standard chemotherapy, were treated with escalating doses of Lipoxal® once weekly for 8 weeks. No serious side effects were observed at doses of 100-250 mg/m2 , whereas at doses of 300 and 350 mg/m2 of Lipoxal® monotherapy mild myelotoxicity, nausea and peripheral neuropathy were observed. Gastrointestinal tract toxicity after treatment with Lipoxal® was negligible. Nausea or mild vomiting was observed, but it was eliminated by administering ondansetron. The most common toxicity is peripheral neuropathy at the 300 and 350 mg/m2 dose levels. Lipoxal® is well-tolerated and reduces significantly all other side effects of free oxaliplatin, especially myelotoxicity and gastrointes‐

**Figure 9.** Chemical structures of principal anthracyclines.

tinal tract toxicity. These preliminary results showed adequate effectiveness in pretreated patients [98,99].

**Figure 8.** Chemical structure of oxaliplatin.

#### **6.2. Anthracyclines**

tively, when compared with free CDDP treatment, thus indicating its high retention within

In addition, MTD values obtained after i.v. and i.p. administration of SpHL-CDDP in healthy mice were approximately three times higher than those obtained using free CDDP. Hemato‐ logical investigations revealed no alterations in red and white blood cell counts upon i.v. and i.p. administration of SpHL-CDDP at a dose corresponding to the MTD in mice. In addition, SpHL-CDDP treatment caused no pronounced alterations in the blood urea and creatinine levels, nor did it induce morphological alterations in the kidneys of the mice [93, 94]. These findings indicate that the use of SpHL-CDDP as a drug delivery system can increase the safety of the drug and improve the therapeutic efficacy of the CDDP-based treatment. Thus, antitu‐ mor activity studies were conducted, and the results showed a significant reduction in the tumor volume, a higher tumor growth inhibition ratio, and the complete remission of the tumor in 18.2% of the Ehrlich solid tumor-bearing mice treated with SpHL-CDDP by intrave‐ nous route, as compared to the free CDDP treatment [94, 95]. In addition, the survival of animals treated with SpH-CDDP was higher than those treated with free CDDP after i.p. administration in initial or disseminated Ehrlich ascitic tumor-bearing mice [96]. These

findings strongly indicate the potential of SpHL-CDDP for future clinical studies.

Oxaliplatin (Figure 8), an analoge of CDDP, has shown a good *in vitro* and *in vivo* antitumor effect and a better safety profile than cisplatin. However, the use of oxaliplatin is associated with side-effects which include neurotoxicity, hematologic toxicity and gastrointestinal tract toxicity. In addition, there is a significant risk of grade 3/4 neutropenia to the patients, and the occurrence of nausea and vomiting were generally mild to moderate. Nephrotoxicity is mild, allowing for the administration of oxaliplatin without hydration. Often, severe side effects can be observed, such as tubular necrosis. Furthermore, cellular resistance to free oxaliplatin has been observed, preventing the potential efficacy of free oxaliplatin [97]. Lipoxal® is a liposomal formulation of oxaliplatin made up of hydrogenated soy phospahatidylcholine (HSPC)/DPPG/ CHOL/DSPE-PEG. This liposomal formulation containing oxaliplatin has also proven to induce the complete disappearance of human breast cancers in mice after 6 intravenous injections with 4 days intervals at a dose of 16 mg/Kg. On the other hand, the free oxaliplatin at its MTD could only cause shrinkage, not the disappearance of tumors. To estimate the adverse reactions and detect the dose limiting toxicity (DLT), as well as the MTD of Lipoxal®, a Phase I clinical study was conducted. Twenty-seven patients with advanced disease of the gastrointestinal system (stage IV gastrointestinal cancers, including colorectal, gastric, and pancreatic), who had failed previous standard chemotherapy, were treated with escalating doses of Lipoxal® once weekly for 8 weeks. No serious side effects were observed at doses of

, whereas at doses of 300 and 350 mg/m2 of Lipoxal® monotherapy mild

dose levels. Lipoxal® is well-tolerated and reduces

myelotoxicity, nausea and peripheral neuropathy were observed. Gastrointestinal tract toxicity after treatment with Lipoxal® was negligible. Nausea or mild vomiting was observed, but it was eliminated by administering ondansetron. The most common toxicity is peripheral

significantly all other side effects of free oxaliplatin, especially myelotoxicity and gastrointes‐

the peritoneal cavity.

104 Cancer Treatment - Conventional and Innovative Approaches

100-250 mg/m2

neuropathy at the 300 and 350 mg/m2

The anthracyclines, represented by doxorubicin, daunorubicin, and their derivatives (Figure 9), are widely used in the treatment of several hematological and solid tumors and are considered to be a first-line therapy for advanced breast cancer [100]. Although conventional anthracyclines have been extensively used for the treatment of a variety of cancers, they can be associated with the development of substantial cardiotoxicity, which is both cumulative and irreversible. Furthermore, cardiotoxicity can be increased nearly four-fold when these drugs are administered in association with other chemotherapeutic drugs [101]. In this case, the preclinical and clinical studies have focused on the development of liposomal formulations, aimed at decreasing the acute and cumulative cardiotoxicity, in addition to attenuating other drug-related events (e.g. bone marrow depression, alopecia, and nausea) [102].

Forssen and coworkers [103] reported the ability of liposomes containing daunorubicin (DNR), made up of DSPC/CHOL, to accumulate within the P-1798 murine lymphosarcoma and MA16C mammary adenocarcinona tumor model. The maximum levels of liposome uptake exceeded those achieved by the free drug between 2.5 and 20-fold, which was translated into a 10-fold increase in AUC of tumor exposure to DNR in the P-1798 system. Other investigations also significantly demonstrated increased efficacy and decreased toxicity of liposomes containing daunorubicin (DaunoXome®), as compared to free drug in the treatment of acute leukemia and advanced cutaneous T-cell lymphoma [104, 105]. In phase I/II clinical trials, DaunoXome® administration produced a 35-fold increase in the plasma AUC, higher peak plasma concentrations, a smaller distribution volume, and a lower total body clearance, when compared to free DNR [106]. Safety results from the combined phase I and II studies showed DaunoXome® to be especially well-tolerated with minimal myelosuppression, no evidence of cardiac toxicity, and a decrease in the frequency and severity of chemotherapy-related side effects when compared with free DNR. The MTD of liposomal DNR was set at 90 mg/m2 .

efficacy and a lower toxicity than does the association of free DXR and cyclophosphamide at

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 107

Thetissuedistribution,efficacy,andtoxicityofDXRencapsulatedinalong-circulatingliposomal formulation made up of HSPC/DSPE-PEG2000/CHOL (Doxil®/Caelyx®) were also investigated. Therapeutic efficacy studies performed in different animal models demonstrated that Doxil®/ Caelyx® was significantly more active than free DXR [113, 114]. A tissue distribution study of this formulation indicated a preferential accumulation within various implanted tumors and human tumor xenografts, with an enhancement of drug concentrations, when compared with freedrug,inthe tumors.Inaddition,the cardiac toxicityofDoxil®, as comparedtofreeDXR,was

Doxil®/Caelix® was the first and is still the only long-circulating liposome formulation to be approved in both the USA and Europe to treat Kaposi's sarcoma and recurrent ovarian cancer [116, 117]. In association with Velcade®(Bortezomib), this drug is approved by the FDA for the treatment of multiple myeloma. In Europe, this drug is still approved for the treatment of metastatic breast cancer. When compared to free DXR, Doxil® presents a lower plasma clearance (0.1 vs. 25 L/hour for Doxil® and free DXR, respectively) and a small distribuition volume (4 vs. 200 L). Doxil® presents two distribution phases: an initial phase with a half-life of 1-3 hours and a second phase with a half-life of 30-90 hours. Its half-life is longer than the free DXR (0.2 hours). Due to this, its cardiotoxicity, myelosuppression, alopecia, and nausea are significantly reduced when compared with an equieffective dose of free DXR. It has also been demonstrated that nearly all circulating drugs (>98%) are used in liposome-encapsulated form, indicating that the pharmacokinetics of liposomal DXR is governed by the liposome carrier and that most of the drug is delivered to the tissues in liposome-associated form [115]. Several studies are currently in progress using Doxil®/Caelix® to treat other malignancies, such

Another important drug in cancer therapy is paclitaxel. This is an alkaloid which stabilizes microtubules and inhibits endothelial cell proliferation, motility, and tube formation [121]. Some studies have presented difficulties in the development of liposomes containing paclitaxel due to its hydrophobic nature. Zhang and coworkers [122] developed a liposomal formulation of paclitaxel consisting of 1,2-dioleyl-sn-glycero-3-phosphocholine/ CHOL /cardiolipin (LEP-ETU). Therapeutic efficacy studies performed in a mouse xenograft model of human ovarian (OVCAR-3), human lung (A-549), breast (MX-1), and prostate (PC-3) cancer, as compared to the administration of free drugs, demonstrated greater tumor growth inhibition after the administration of liposomal paclitaxel. In addition, toxicology studies have shown that liposomal paclitaxel is less toxic than free paclitaxel. An improved pegylated liposomal formulation of paclitaxel was developed, demonstrating that cytotoxicity in human breast cancer cell lines (MDA-MB-231 and SK-BR-3) of the tested paclitaxel formulation was equi‐ potent after 72 h of incubation, when compared to Taxol®. The pegylated liposomes, as compared to the conventional liposomes, increased the biological half-life of paclitaxel from 5.05 ± 1.52 h to 17.8 ± 2.35 h in rats. Biodistribution studies in a breast cancer xenograft nude

the same dose. The cardiotoxicity was dramatically reduced (21% vs. 6%).

as breast cancer and recurrent high-grade glioma [118-120].

**6.3. Other chemotherapeutic agents**

significantly reduced [115].

A randomized phase III trial was conducted to compare the safety and efficacy of DaunoX‐ ome® with that of a reference regimen of doxorubicin, bleomycin, and vincristine (ABV) as a primary therapy in advanced AIDS-related Kaposi's sarcoma. DaunoXome® presented an efficacy that was comparable to ABV, presented significantly less alopecia and neuropathy, and showed no evidence of cardiac toxicity [107]. In 1996, DaunoXome® was approved as a first-line therapy for HIV-related Kaposi's sarcoma by the FDA and the EMA. A European Phase IV study, carried out over a one year period after DaunoXome® had been approved for commercialization, demonstrated the treatment's good tolerability (absence of cardiotoxicity) and effectiveness. Furthermore, the concomitant administration of highly active antiretroviral treatment (HAART) also proved to be safe [108].

Another commercial product of conventional liposome (Myocet®), in combination with cyclophosphamide, has been approved in Europe as a first-line treatment of breast cancer. This liposome consists of egg phosphatidilcholine (EPC)/ CHOL and encapsulated doxorubicin (DXR). Preclinical toxicity studies performed on Beagles demonstrated a better toxicity profile of Myocet®, as compared to free DXR [109]. The ability of Myocet® to locate tumors could be observed in ascitic (L1210 ascitic lymphoma) and solid tumor (murine Lewis lung cancer and B16/BL6 melanoma) models, as reported in findings from Harasym and coworkers [110]. In the case of the solid tumor models, the maximum tumor concentrations were two to three-fold higher for liposomal DXR, as compared to free DXR. For the ascitic model, the maximal level in tumor drug exposure was ten-fold higher for liposomal DXR, as compared to free DXR. These findings supported the choice of Myocet® for clinical studies.

Some studies have shown that the replacement of free DXR by Myocet®, combined with cyclophosphamide, does not result in decreased efficacy parameters, but rather in a signifi‐ cantly reduced risk of cardiotoxicity [56]. A phase III comparison of free DXR with Myocet® in patients with metastatic breast cancer, for instance, demonstrated that, at comparable response rates (RR: 26% for both) and progression-free survival times (PFS: 4 months for both), the incidence of cardiac events (29% vs. 13%) and of congestive heart failure (8% vs. 2%) were significantly lower for Myocet® [102].

Cowens and coworkers [111] carried out a phase I study in 38 patients with refractory solid tumors and demonstrated diminished myelosupression and gastrointestinal toxicity after the intravenous injection of Myocet®, as compared to findings for free DXR at the same dose. The MTD for Myocet® was established as 90 mg/m2 . A multicentric study including 297 patients with metastatic breast cancer, carried out by Batist and coworkers [112], demonstrated that the combination of Myocet® (60 mg/m2 ) with cyclophosphamide (600 mg/m2 ) presents a similar efficacy and a lower toxicity than does the association of free DXR and cyclophosphamide at the same dose. The cardiotoxicity was dramatically reduced (21% vs. 6%).

Thetissuedistribution,efficacy,andtoxicityofDXRencapsulatedinalong-circulatingliposomal formulation made up of HSPC/DSPE-PEG2000/CHOL (Doxil®/Caelyx®) were also investigated. Therapeutic efficacy studies performed in different animal models demonstrated that Doxil®/ Caelyx® was significantly more active than free DXR [113, 114]. A tissue distribution study of this formulation indicated a preferential accumulation within various implanted tumors and human tumor xenografts, with an enhancement of drug concentrations, when compared with freedrug,inthe tumors.Inaddition,the cardiac toxicityofDoxil®, as comparedtofreeDXR,was significantly reduced [115].

Doxil®/Caelix® was the first and is still the only long-circulating liposome formulation to be approved in both the USA and Europe to treat Kaposi's sarcoma and recurrent ovarian cancer [116, 117]. In association with Velcade®(Bortezomib), this drug is approved by the FDA for the treatment of multiple myeloma. In Europe, this drug is still approved for the treatment of metastatic breast cancer. When compared to free DXR, Doxil® presents a lower plasma clearance (0.1 vs. 25 L/hour for Doxil® and free DXR, respectively) and a small distribuition volume (4 vs. 200 L). Doxil® presents two distribution phases: an initial phase with a half-life of 1-3 hours and a second phase with a half-life of 30-90 hours. Its half-life is longer than the free DXR (0.2 hours). Due to this, its cardiotoxicity, myelosuppression, alopecia, and nausea are significantly reduced when compared with an equieffective dose of free DXR. It has also been demonstrated that nearly all circulating drugs (>98%) are used in liposome-encapsulated form, indicating that the pharmacokinetics of liposomal DXR is governed by the liposome carrier and that most of the drug is delivered to the tissues in liposome-associated form [115]. Several studies are currently in progress using Doxil®/Caelix® to treat other malignancies, such as breast cancer and recurrent high-grade glioma [118-120].

### **6.3. Other chemotherapeutic agents**

containing daunorubicin (DaunoXome®), as compared to free drug in the treatment of acute leukemia and advanced cutaneous T-cell lymphoma [104, 105]. In phase I/II clinical trials, DaunoXome® administration produced a 35-fold increase in the plasma AUC, higher peak plasma concentrations, a smaller distribution volume, and a lower total body clearance, when compared to free DNR [106]. Safety results from the combined phase I and II studies showed DaunoXome® to be especially well-tolerated with minimal myelosuppression, no evidence of cardiac toxicity, and a decrease in the frequency and severity of chemotherapy-related side effects when compared with free DNR. The MTD of liposomal DNR was set at 90 mg/m2

A randomized phase III trial was conducted to compare the safety and efficacy of DaunoX‐ ome® with that of a reference regimen of doxorubicin, bleomycin, and vincristine (ABV) as a primary therapy in advanced AIDS-related Kaposi's sarcoma. DaunoXome® presented an efficacy that was comparable to ABV, presented significantly less alopecia and neuropathy, and showed no evidence of cardiac toxicity [107]. In 1996, DaunoXome® was approved as a first-line therapy for HIV-related Kaposi's sarcoma by the FDA and the EMA. A European Phase IV study, carried out over a one year period after DaunoXome® had been approved for commercialization, demonstrated the treatment's good tolerability (absence of cardiotoxicity) and effectiveness. Furthermore, the concomitant administration of highly active antiretroviral

Another commercial product of conventional liposome (Myocet®), in combination with cyclophosphamide, has been approved in Europe as a first-line treatment of breast cancer. This liposome consists of egg phosphatidilcholine (EPC)/ CHOL and encapsulated doxorubicin (DXR). Preclinical toxicity studies performed on Beagles demonstrated a better toxicity profile of Myocet®, as compared to free DXR [109]. The ability of Myocet® to locate tumors could be observed in ascitic (L1210 ascitic lymphoma) and solid tumor (murine Lewis lung cancer and B16/BL6 melanoma) models, as reported in findings from Harasym and coworkers [110]. In the case of the solid tumor models, the maximum tumor concentrations were two to three-fold higher for liposomal DXR, as compared to free DXR. For the ascitic model, the maximal level in tumor drug exposure was ten-fold higher for liposomal DXR, as compared to free DXR.

Some studies have shown that the replacement of free DXR by Myocet®, combined with cyclophosphamide, does not result in decreased efficacy parameters, but rather in a signifi‐ cantly reduced risk of cardiotoxicity [56]. A phase III comparison of free DXR with Myocet® in patients with metastatic breast cancer, for instance, demonstrated that, at comparable response rates (RR: 26% for both) and progression-free survival times (PFS: 4 months for both), the incidence of cardiac events (29% vs. 13%) and of congestive heart failure (8% vs. 2%) were

Cowens and coworkers [111] carried out a phase I study in 38 patients with refractory solid tumors and demonstrated diminished myelosupression and gastrointestinal toxicity after the intravenous injection of Myocet®, as compared to findings for free DXR at the same dose. The

with metastatic breast cancer, carried out by Batist and coworkers [112], demonstrated that the

) with cyclophosphamide (600 mg/m2

. A multicentric study including 297 patients

) presents a similar

treatment (HAART) also proved to be safe [108].

106 Cancer Treatment - Conventional and Innovative Approaches

significantly lower for Myocet® [102].

combination of Myocet® (60 mg/m2

MTD for Myocet® was established as 90 mg/m2

These findings supported the choice of Myocet® for clinical studies.

.

Another important drug in cancer therapy is paclitaxel. This is an alkaloid which stabilizes microtubules and inhibits endothelial cell proliferation, motility, and tube formation [121]. Some studies have presented difficulties in the development of liposomes containing paclitaxel due to its hydrophobic nature. Zhang and coworkers [122] developed a liposomal formulation of paclitaxel consisting of 1,2-dioleyl-sn-glycero-3-phosphocholine/ CHOL /cardiolipin (LEP-ETU). Therapeutic efficacy studies performed in a mouse xenograft model of human ovarian (OVCAR-3), human lung (A-549), breast (MX-1), and prostate (PC-3) cancer, as compared to the administration of free drugs, demonstrated greater tumor growth inhibition after the administration of liposomal paclitaxel. In addition, toxicology studies have shown that liposomal paclitaxel is less toxic than free paclitaxel. An improved pegylated liposomal formulation of paclitaxel was developed, demonstrating that cytotoxicity in human breast cancer cell lines (MDA-MB-231 and SK-BR-3) of the tested paclitaxel formulation was equi‐ potent after 72 h of incubation, when compared to Taxol®. The pegylated liposomes, as compared to the conventional liposomes, increased the biological half-life of paclitaxel from 5.05 ± 1.52 h to 17.8 ± 2.35 h in rats. Biodistribution studies in a breast cancer xenograft nude mouse model demonstrated that the uptake of these liposomes significantly increased in tumor tissues after their injection, as compared to Taxol® or the conventional liposomal formulation. Moreover, the pegylated liposome showed a greater tumor growth inhibition effect in *in vivo* studies [123]. In a study by Strieth et al. (2008) [124], paclitaxel was encapsulated in cationic liposomes composed of dioleytrimethylammoniumpropane (DOTAP)/DOPC (EndoTAG-1) as a vascular targeting formulation to treat solid tumors and quantified the therapeutic combi‐ nation with conventional CDDP chemotherapy. This study showed that vascular targeting with EndoTAG-1 increased tumor microvessel leakage, most likely due to vascular damage, and concluded that manipulating the blood-tumor barrier by repeated tumor microvessel targeting using EndoTAG-1 can effectively be combined with tumor cell directed conventional cisplatin chemotherapy.

Marqibo®, a DSPC/CHOL encapsulation of vincristine sulfate has targeted, increased, and sustained the delivery of vincristine to tumor tissues. A phase II study evaluated the efficacy and tolerability of Marqibo® as a single agent in patients with multiple relapsed or refractory aggressive non-Hodgkin lymphoma (NHL). In this study, eligible patients again presented relapsed, refractory, or transformed aggressive NHL and prior treatment with at least 2

for a maximum of 12 cycles or until toxicity or disease progression had been resolved. Marqibo® proved to be an active agent in patients with heavily pretreated aggressive NHL and

Considering that tumor cells are often characterized by a specific expression pattern of membrane associated proteins, such as receptors, membrane transport systems, or adhesion molecules, cancer therapies that exploit targeting ligands to deliver attached cytotoxic drugs selectively to malignant cells are currently receiving significant attention and are being recognized as an effective strategy for increasing the therapeutic indices of anticancer drugs. In an attempt to improve the binding and cellular internalization of liposomes in the tumor area, several ligands were attached to the liposome surface, including monoclonal antibodies, folate, transferrin, vasoactive intestinal peptide (VIP), epidermal growth factor (EGF), hyalur‐

The majority of research in this area is related to cancer targeting, which uses a variety of monoclonal antibodies. To target HER2-overexpressing tumors, it was suggested that anti-HER2 long-circulating liposomes be used. Antibody CC52 against rat colon adenocarcinoma CC531 attached to pegylated liposomes provided a specific accumulation of liposomes in rat model of metastatic CC531. A nucleosome-specific monoclonal antibody (mAb 2C5) capable of recognizing various tumor cells through the tumor cell surface-bound nucleosomes significantly improved Doxil®, by targeting to tumor cells, and increased its cytotoxicity both *in vitro* and *in vivo* in different testing systems, including the intracranial human brain U-87 tumor xenograft in nude mice. The same antibody was also used to effectively target longcirculating liposomes loaded with an agent for tumor photodynamic therapy (PDT) for both multiple cancer cells *in vitro* and experimental tumors *in vivo*, and provided a significantly

Previous studies have demonstrated that DXR-loaded long-circulating liposomes prolong circulation in the blood but create a steric barrier that could cause a reduction in the interaction of liposomes with the target cells [131]. In this light, XueMing Li and coworkers [132] prepared DXR-loaded long-circulating liposomes conjugated with transferrin (Tf) and observed that Tfmodified liposomes could be used to enhance the intracellular delivery of anticancer agents,

Saccharide molecules represent good models for tumor targeting molecules, as many malig‐ nant cells express the lectin, sugar-binding protein. In this context, Song and coworkers [133] investigated the *in vitro* characteristics of liposomes consisting of HSPC/CHOL/DSPE-PEG2000 disaccharide whose surface had been modified with a disaccharide molecule, sucrose, or

such as cytotoxic drugs, antisense nucleic acids, ribozymes, or imaging agents.

to be tolerated at approximately twice the dose intensity of standard vincristine [128].

, every 2 weeks,

109

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290

multiagent chemotherapy regimens. Marqibo® was administered at 2 mg/m2

**6.4. Recent advances in targeted liposomes**

onan, galactosides, and condroitin sulphate [129, 130].

enhanced elimination of tumor cells under PDT conditions [5].

In a study by Strieth and coworkers, paclitaxel was encapsulated in cationic liposomes com‐ posed of dioleytrimethylammoniumpropane (DOTAP)/dioleoylphosphatidylcholine (DOPC) (EndoTAG-1) as a vascular targeting formulation to treat solid tumors and quanti‐ fied the therapeutic combination with conventional cisplatin chemotherapy. This study showed that vascular targeting with EndoTAG-1 increased tumor microvessel leakage, most likely due to vascular damage, and concluded that manipulating the blood-tumor barrier by repeated tumor microvessel targeting using EndoTAG-1 can effectively be combined with tumor cell directed conventional cisplatin chemotherapy [124].

Another formulation approved in Europe for lymphomatous meningitis is DepoCyte®, a sustained-release formulation of cytarabine. A randomized study to evaluate the efficacy and safety of this liposomal formulation, in comparison with free drug, was performed in 28 patients with lymphomatous meningitis. While the reference treatment required the admin‐ istration of free cytarabine biweekly, it could be observed that the administration of Depo‐ cyte® intrathecal maintains cytotoxic concentrations of the drug in the cerebrospinal fluid of most patients for more than 14 days. Response rates (i.e. clearing of cerebrospinal fluid and absence of neurological progression) were significantly higher in Depocyte®. In addition, the less demanding injection schedule is favorable to the patients' quality of life. The major adverse events were headache and arachnoiditis, which were often caused by the underlying disease [125]. Another randomized trial compared DepoCyte® with methotrexate in patients with solid tumor neoplastic meningitis. The results showed that median survival was not different, but a greater median time to neurological progression was obtained with DepoCyte®. The frequency and grade of adverse events were comparable between treatments [126]. More recently, a phase II study of intrathecal liposomal cytarabine was performed at the dose of 50 mg in 30 patients with human immunodeficiency virus–non-Hodgkin lymphoma (HIV-NHL) to evaluate the feasibility and activity of prophylaxis. In this study, liposomal cytarabine was well-tolerated, with a headache of grade I to III being the most frequent side effect in 40% of the patients. With a median follow-up of 10.5 months, only 1 (3%) patient developed a combined systemic and meningeal recurrence. The use of liposomal cytarabine allowed for a significant reduction in the number of lumbar injections, as compared to the standard sched‐ ules (approximately 50%), improving the patients' quality of life and reducing their risk of professional exposure [127]

Marqibo®, a DSPC/CHOL encapsulation of vincristine sulfate has targeted, increased, and sustained the delivery of vincristine to tumor tissues. A phase II study evaluated the efficacy and tolerability of Marqibo® as a single agent in patients with multiple relapsed or refractory aggressive non-Hodgkin lymphoma (NHL). In this study, eligible patients again presented relapsed, refractory, or transformed aggressive NHL and prior treatment with at least 2 multiagent chemotherapy regimens. Marqibo® was administered at 2 mg/m2 , every 2 weeks, for a maximum of 12 cycles or until toxicity or disease progression had been resolved. Marqibo® proved to be an active agent in patients with heavily pretreated aggressive NHL and to be tolerated at approximately twice the dose intensity of standard vincristine [128].

### **6.4. Recent advances in targeted liposomes**

mouse model demonstrated that the uptake of these liposomes significantly increased in tumor tissues after their injection, as compared to Taxol® or the conventional liposomal formulation. Moreover, the pegylated liposome showed a greater tumor growth inhibition effect in *in vivo* studies [123]. In a study by Strieth et al. (2008) [124], paclitaxel was encapsulated in cationic liposomes composed of dioleytrimethylammoniumpropane (DOTAP)/DOPC (EndoTAG-1) as a vascular targeting formulation to treat solid tumors and quantified the therapeutic combi‐ nation with conventional CDDP chemotherapy. This study showed that vascular targeting with EndoTAG-1 increased tumor microvessel leakage, most likely due to vascular damage, and concluded that manipulating the blood-tumor barrier by repeated tumor microvessel targeting using EndoTAG-1 can effectively be combined with tumor cell directed conventional

In a study by Strieth and coworkers, paclitaxel was encapsulated in cationic liposomes com‐ posed of dioleytrimethylammoniumpropane (DOTAP)/dioleoylphosphatidylcholine (DOPC) (EndoTAG-1) as a vascular targeting formulation to treat solid tumors and quanti‐ fied the therapeutic combination with conventional cisplatin chemotherapy. This study showed that vascular targeting with EndoTAG-1 increased tumor microvessel leakage, most likely due to vascular damage, and concluded that manipulating the blood-tumor barrier by repeated tumor microvessel targeting using EndoTAG-1 can effectively be combined with

Another formulation approved in Europe for lymphomatous meningitis is DepoCyte®, a sustained-release formulation of cytarabine. A randomized study to evaluate the efficacy and safety of this liposomal formulation, in comparison with free drug, was performed in 28 patients with lymphomatous meningitis. While the reference treatment required the admin‐ istration of free cytarabine biweekly, it could be observed that the administration of Depo‐ cyte® intrathecal maintains cytotoxic concentrations of the drug in the cerebrospinal fluid of most patients for more than 14 days. Response rates (i.e. clearing of cerebrospinal fluid and absence of neurological progression) were significantly higher in Depocyte®. In addition, the less demanding injection schedule is favorable to the patients' quality of life. The major adverse events were headache and arachnoiditis, which were often caused by the underlying disease [125]. Another randomized trial compared DepoCyte® with methotrexate in patients with solid tumor neoplastic meningitis. The results showed that median survival was not different, but a greater median time to neurological progression was obtained with DepoCyte®. The frequency and grade of adverse events were comparable between treatments [126]. More recently, a phase II study of intrathecal liposomal cytarabine was performed at the dose of 50 mg in 30 patients with human immunodeficiency virus–non-Hodgkin lymphoma (HIV-NHL) to evaluate the feasibility and activity of prophylaxis. In this study, liposomal cytarabine was well-tolerated, with a headache of grade I to III being the most frequent side effect in 40% of the patients. With a median follow-up of 10.5 months, only 1 (3%) patient developed a combined systemic and meningeal recurrence. The use of liposomal cytarabine allowed for a significant reduction in the number of lumbar injections, as compared to the standard sched‐ ules (approximately 50%), improving the patients' quality of life and reducing their risk of

tumor cell directed conventional cisplatin chemotherapy [124].

cisplatin chemotherapy.

108 Cancer Treatment - Conventional and Innovative Approaches

professional exposure [127]

Considering that tumor cells are often characterized by a specific expression pattern of membrane associated proteins, such as receptors, membrane transport systems, or adhesion molecules, cancer therapies that exploit targeting ligands to deliver attached cytotoxic drugs selectively to malignant cells are currently receiving significant attention and are being recognized as an effective strategy for increasing the therapeutic indices of anticancer drugs. In an attempt to improve the binding and cellular internalization of liposomes in the tumor area, several ligands were attached to the liposome surface, including monoclonal antibodies, folate, transferrin, vasoactive intestinal peptide (VIP), epidermal growth factor (EGF), hyalur‐ onan, galactosides, and condroitin sulphate [129, 130].

The majority of research in this area is related to cancer targeting, which uses a variety of monoclonal antibodies. To target HER2-overexpressing tumors, it was suggested that anti-HER2 long-circulating liposomes be used. Antibody CC52 against rat colon adenocarcinoma CC531 attached to pegylated liposomes provided a specific accumulation of liposomes in rat model of metastatic CC531. A nucleosome-specific monoclonal antibody (mAb 2C5) capable of recognizing various tumor cells through the tumor cell surface-bound nucleosomes significantly improved Doxil®, by targeting to tumor cells, and increased its cytotoxicity both *in vitro* and *in vivo* in different testing systems, including the intracranial human brain U-87 tumor xenograft in nude mice. The same antibody was also used to effectively target longcirculating liposomes loaded with an agent for tumor photodynamic therapy (PDT) for both multiple cancer cells *in vitro* and experimental tumors *in vivo*, and provided a significantly enhanced elimination of tumor cells under PDT conditions [5].

Previous studies have demonstrated that DXR-loaded long-circulating liposomes prolong circulation in the blood but create a steric barrier that could cause a reduction in the interaction of liposomes with the target cells [131]. In this light, XueMing Li and coworkers [132] prepared DXR-loaded long-circulating liposomes conjugated with transferrin (Tf) and observed that Tfmodified liposomes could be used to enhance the intracellular delivery of anticancer agents, such as cytotoxic drugs, antisense nucleic acids, ribozymes, or imaging agents.

Saccharide molecules represent good models for tumor targeting molecules, as many malig‐ nant cells express the lectin, sugar-binding protein. In this context, Song and coworkers [133] investigated the *in vitro* characteristics of liposomes consisting of HSPC/CHOL/DSPE-PEG2000 disaccharide whose surface had been modified with a disaccharide molecule, sucrose, or maltose and that were then loaded with DXR. They concluded that disaccharide-modified liposomes may be promising cancer targeting carriers which can enhance intracellular uptake and cytotoxicity of the drug-loaded liposomes by means of lectin-mediated endocytosis.

**Product Entrapped**

LE-SN38® Irinotecan metabolite

OSI-7904L® Thimidylate synthase

CPX-351 Cytarabine and

CPX-1 Irinotecan and

OSI-211®

a

**Drug**

SN38

inhibitor

Daunorubicin

floxuridine

**7. Future perspectives and challenges**

**Lipid composition Company Therapeutic Indication Statusa**

DSPC/CHOL NeoPharm Colorectal and lung cancer P II

HSPC/CHOL OSI Colorectal cancer P II

Pharmaceuticals

Pharmaceuticals

acute lymphoblastic leukemia, and Hodgkin's lymphoma

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290

lung cancer

breast cancer

Acute myeloid leukemia P II

Advanced colorectal cancer P II

P III

111

P III

P I

Marqibo® Vincristine DSPC/CHOL Talonn Therapeutics Non-Hodgkin's lymphoma,

(NX211) Lurtotecan HSPC/CHOL OSI Ovarian cancer and small cell

INX-0076® Topotecan Sphingomyelin/CHOL Inex Ovarian and small lung cancer P II Alocrest® vinorelbine Sphingomyelin/CHOL Inex Non-small cell lung cancer and

Oncolipin® Interleukin 2 DMPC Biomirma USA Inc kidney cancer P II

DSPC/DSPG/CHOL Celator

DSPC/DSPG/CHOL Celator

HSPC, hydrogenated soy phosphatidylcholine; CHOL, cholesterol; DSPE-PEG2000, distearoylphosphatidylethanolamine‐ polyethyleneglycol2000; EPC, egg phosphatidylcholine; DSPC, distearoylphosphatidylcholine; SPC, soy phosphatidylcho‐ line; DOPC, dioleylphosphatidylcholine; DOTAP, dioleytrimethylammoniumpropane; DMPC, dimyristoyl

This chapter focused on liposome-based drug delivery systems, which are the most widely used drug nanoparticles in cancer treatments. Basic concepts were presented concerning liposomes and an overview of the clinically used and tested liposomes for the treatment of cancer. It has been demonstrated, based on prior studies, that liposomes offer safety and

The greater interest in the development of these sophisticated drug delivery systems is to improve the efficacy and decrease the side effects of new and old anti-cancer drugs. In this context, the optimized pharmacokinetic properties of liposomes, resulting in an improved

Other new strategies in the biology and pharmacokinetic behavior of liposomes, such as the anti-angiogenic properties of cationic liposomes, as well as the development of immunolipo‐

A = approved, PI = phase I study, PII = phase II study, PIII = phase III study; bapproved by EMA

**Table 5.** Approved and emerging liposome encapsulated anticancer drugs.

effectiveness as compared to other conventional treatments.

toxicity profile, is still the main argument for the use of liposomal carriers.

phophatidylcholine; DSPG, Distearoylphosphatidylglycerol; MSPC, Myristoylstearoylphosphatidylcholine

One approach that has received considerable attention has been the use of folic acid to deliver drugs selectively to folate receptor-expressing cancer cells [130]. Studies of folate-conjugated liposomes containing DNR or DXR showed an increased cytotoxicity of the encapsulated anticancer drugs in various tumor cells [134, 135]. The i.v. administration of anti-tumorassociated glycoprotein (TAG)-72 Polyethyleneglycol (PEG)-immunoliposomes showed that they were more effectively located in LS174 T human colon cancer cells than conventional liposomes [136]. It is worth noting that the co-immobilization of PEG and ligands on the same surface liposome can in fact lead to poor target recognition due to a steric hindrance by the hydrophilic corona [137]. Thus, it has been suggested that targeting vectors be attached to the distal end of pegylated phospholipids [138].

Several liposomal formulations of anticancer drugs have also been investigated in preclinical tumor models and many liposomal preparations of anticancer drugs have been approved for cancer chemotherapy or are in advanced stages of clinical development. Some of these products are listed in Table 5.



a A = approved, PI = phase I study, PII = phase II study, PIII = phase III study; bapproved by EMA

HSPC, hydrogenated soy phosphatidylcholine; CHOL, cholesterol; DSPE-PEG2000, distearoylphosphatidylethanolamine‐ polyethyleneglycol2000; EPC, egg phosphatidylcholine; DSPC, distearoylphosphatidylcholine; SPC, soy phosphatidylcho‐ line; DOPC, dioleylphosphatidylcholine; DOTAP, dioleytrimethylammoniumpropane; DMPC, dimyristoyl phophatidylcholine; DSPG, Distearoylphosphatidylglycerol; MSPC, Myristoylstearoylphosphatidylcholine

**Table 5.** Approved and emerging liposome encapsulated anticancer drugs.

### **7. Future perspectives and challenges**

maltose and that were then loaded with DXR. They concluded that disaccharide-modified liposomes may be promising cancer targeting carriers which can enhance intracellular uptake and cytotoxicity of the drug-loaded liposomes by means of lectin-mediated endocytosis.

One approach that has received considerable attention has been the use of folic acid to deliver drugs selectively to folate receptor-expressing cancer cells [130]. Studies of folate-conjugated liposomes containing DNR or DXR showed an increased cytotoxicity of the encapsulated anticancer drugs in various tumor cells [134, 135]. The i.v. administration of anti-tumorassociated glycoprotein (TAG)-72 Polyethyleneglycol (PEG)-immunoliposomes showed that they were more effectively located in LS174 T human colon cancer cells than conventional liposomes [136]. It is worth noting that the co-immobilization of PEG and ligands on the same surface liposome can in fact lead to poor target recognition due to a steric hindrance by the hydrophilic corona [137]. Thus, it has been suggested that targeting vectors be attached to the

Several liposomal formulations of anticancer drugs have also been investigated in preclinical tumor models and many liposomal preparations of anticancer drugs have been approved for cancer chemotherapy or are in advanced stages of clinical development. Some of these

Myocet® Doxorubicin EPC/CHOL Cephalon Metastatic breast cancer Ab DaunoXome® Daunorubicin DSPC/CHOL Galen US Kaposi's sarcoma A

SPI-077® Cisplatin HSPC/CHOL/DSPE-PEG2000 Sequus Ovarian cancer P II

**Lipid composition Company Therapeutic Indication Statusa**

DMPC/DMPG Aronex Colorectal, lung, and pancreatic

Janssen-Cilag Kaposi's sarcoma, recurrent

ovarian, multiple myeloma, and metastatic breast cancer

Pacira Lymphomatous meningitis A

Regulon Lung cancer P III

Insys Therapeutics Breast, lung, ovarian cancer P II

cancer

cancer

hepatocelular cancer

A

P II

P II

P II

distal end of pegylated phospholipids [138].

110 Cancer Treatment - Conventional and Innovative Approaches

**Drug**

DepoCyte® Cytarabine DOPC/DPPG/CHOL/

Lipoplatin® Cisplatin DPPG/SPC/CHOL/

diaminocyclohexane platinum

LEP-ETU® Paclitaxel DOPC/CHOL/

Doxorubicin HSPC/CHOL/ DSPE-

PEG2000

TRIOLEIN

DSPE-PEG2000

CARDIOLIPIN

EndoTAG-1® Paclitaxel DOPC/DOTAP MediGene Breast, pancreatic, and hepatic

ThermoDox® Doxorubicin DPPC/MSPC/DSPE-PEG2000 Celsion Bone metastasis, breast, and

products are listed in Table 5.

**Product Entrapped**

Aroplatin® bis-neodecanoate

Doxil® / Caelyx®

> This chapter focused on liposome-based drug delivery systems, which are the most widely used drug nanoparticles in cancer treatments. Basic concepts were presented concerning liposomes and an overview of the clinically used and tested liposomes for the treatment of cancer. It has been demonstrated, based on prior studies, that liposomes offer safety and effectiveness as compared to other conventional treatments.

> The greater interest in the development of these sophisticated drug delivery systems is to improve the efficacy and decrease the side effects of new and old anti-cancer drugs. In this context, the optimized pharmacokinetic properties of liposomes, resulting in an improved toxicity profile, is still the main argument for the use of liposomal carriers.

> Other new strategies in the biology and pharmacokinetic behavior of liposomes, such as the anti-angiogenic properties of cationic liposomes, as well as the development of immunolipo‐

somes or antisense oligonucleotides, also offer a great therapeutic repertoire for these drug delivery systems.

**References**

592-599.

1990.

307-321.

1975;45(1) 11-20.

235-237.

40-48.

[1] Thassu D, Pathak Y, Dellers M., editors. Nanoparticles Drug Delivery System. Drugs

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 113

[2] Malam Y, Loizidou M, Seifalian AM. Liposomes and nanoparticles: nanosized vehi‐ cles for drug delivery in cancer. Trends in Pharmacological Sciences 2009;30(11)

[3] Raffa V, Vittorio O, Riggio C, Cuschieri A. Progress in nanotechnology for health‐

[4] Tran MA, Watts RJ, Robertson GP. Use of liposomes as drug delivery vehicles for treatment of melanoma. Pigment cell melanoma Research 2009;22(4) 388-399.

[5] Torchilin V. Multifunctional and stimuli-sensitive pharmaceutical nanocarriers. Eu‐ ropean Journal of Pharmaceutics and Biopharmaceutics 2009;71(3) 431–444.

[6] New, RRC. Liposomes: a pratical approach. New York: Oxford University Press;

[7] Lasic, DD. Novel application of liposomes. Trends in Biotechnology 1998;16(7)

[8] Huwyler J, Drewe J, Krähenbühl S. Tumor targeting using liposomal antineoplastic

[9] Frezard F, Silva-Barcelos NM, Santos, RAS. A novel approach based on nanotechnol‐ ogy for investigating the chronic actions of short-lived peptides in specific sites of the

[10] Batista, CM, Carvalho, CMB, Magalhães, NSS. Lipossomas e suas aplicações terapêu‐ ticas: Estado da arte. Brazilian Journal of Pharmaceutical Sciences 2007;43(2) 167-179.

[11] Vemuri S, Rhodes CT. Preparation and characterization of liposomes as therapeutic delivery systems: a review. Pharmaceutica Acta Helvetiae 1995;70(2) 95-111.

[12] Durocher JR, Payne RC, Conrad ME. Role of sialic acid in erythrocyte survival. Blood

[13] Allen TM, Chonn A. Large unilamellar liposomes with low uptake into the reticu‐

[14] Klibanov AL, Maruyama K, Torchilin VP, Huang L. Amphipathic polyethylenegly‐ cols effectively prolong the circulation time of liposomes. FEBS Letters 1990;268(1)

[15] Needham D, McIntosh TJ, Lasic DD. Repulsive interactions and mechanical stability of polymer-grafted lipid membranes. Biochimica et Biophysica Acta 1992;1108(1)

drugs. International Journal of Nanomedicine 2008;3(1) 21–29.

brain. Regulatory Peptides 2007;138(2-3) 59–65.

loendothelial system. FEBS Letters 1987;23(1) 42-46.

and Pharmaceuticals Sciences. London: Informa Healthcare; 2007.

care, Minimally Invasive Therapy 2010;19(3) 127–135.

However,despiteallprogressachievedtodate,itisstillimportanttodiscussnotonlythebenefits, but also the problems, which remain as a challenge in liposome-based drug delivery systems. As reviewed by Ruenraroengsak and coworkers [139], there are many issues regarding the instability of particles through flocculation and aggregation, their complex flow, and adhe‐ sion patterns in the capillary network, the heterogeneity of the access of drugs to specific tumor sites, the diffusion of free drugs, and nanoparticles in tumor tissues as well as in single cells.

The ''passive'' form of encapsulated drug delivery today is still mostly based on leakage in the tumor microenvironment, followed by the possibility of the cellular uptake of the free drug at the tumor site. As a result, many research groups are working on more ''active'' therapies that exploit targeting ligands to deliver attached cytotoxic drugs selectively to malignant cells. These ligands specifically recognize and preferentially bind receptors found on the cells of interest, thereby allowing for a more precise delivery method [140].

Although current studies have shown that the use of these targeted nanoparticles as a drug delivery system is a promising strategy to treat human cancers, it is still in its early stage of development. Clinical data using targeted nanoparticles are limited, since most targeted nanoparticles have not yet reached the clinical level. Only a few targeted nanoparticles are currently under clinical investigation. In addition, advanced imaging techniques are essential, especially in small animals, to verify the true extent of tumor and target localization [139].

In sum, liposomes provide many targeting strategies and have shown a promising future as a new generation of cancer therapeutics. Certain critical questions and many obstacles still remain, which present specific limitations to their overall efficacy. However, as soon as more clinical data becomes available, further understanding will certainly lead to a more rational design of optimized liposomes with improved selectivity, efficacy, and safety in cancer treatment [140].

### **Author details**

Sávia Caldeira de Araújo Lopes1 , Cristiane dos Santos Giuberti1,2, Talita Guieiro Ribeiro Rocha1 , Diêgo dos Santos Ferreira1 , Elaine Amaral Leite3 and Mônica Cristina Oliveira1

1 Department of Pharmaceutical Products, School of Pharmacy, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil

2 Department of Pharmaceutical Sciences, Health Sciences Center, Federal University of Es‐ pirito Santo, Vitória, Brazil

3 Department of Pharmacy, School of Biological and Health Sciences, Federal University of Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil

### **References**

somes or antisense oligonucleotides, also offer a great therapeutic repertoire for these drug

However,despiteallprogressachievedtodate,itisstillimportanttodiscussnotonlythebenefits, but also the problems, which remain as a challenge in liposome-based drug delivery systems. As reviewed by Ruenraroengsak and coworkers [139], there are many issues regarding the instability of particles through flocculation and aggregation, their complex flow, and adhe‐ sion patterns in the capillary network, the heterogeneity of the access of drugs to specific tumor sites, the diffusion of free drugs, and nanoparticles in tumor tissues as well as in single cells.

The ''passive'' form of encapsulated drug delivery today is still mostly based on leakage in the tumor microenvironment, followed by the possibility of the cellular uptake of the free drug at the tumor site. As a result, many research groups are working on more ''active'' therapies that exploit targeting ligands to deliver attached cytotoxic drugs selectively to malignant cells. These ligands specifically recognize and preferentially bind receptors found on the cells of

Although current studies have shown that the use of these targeted nanoparticles as a drug delivery system is a promising strategy to treat human cancers, it is still in its early stage of development. Clinical data using targeted nanoparticles are limited, since most targeted nanoparticles have not yet reached the clinical level. Only a few targeted nanoparticles are currently under clinical investigation. In addition, advanced imaging techniques are essential, especially in small animals, to verify the true extent of tumor and target localization [139].

In sum, liposomes provide many targeting strategies and have shown a promising future as a new generation of cancer therapeutics. Certain critical questions and many obstacles still remain, which present specific limitations to their overall efficacy. However, as soon as more clinical data becomes available, further understanding will certainly lead to a more rational design of optimized liposomes with improved selectivity, efficacy, and safety in cancer

1 Department of Pharmaceutical Products, School of Pharmacy, Federal University of Minas

2 Department of Pharmaceutical Sciences, Health Sciences Center, Federal University of Es‐

3 Department of Pharmacy, School of Biological and Health Sciences, Federal University of

, Cristiane dos Santos Giuberti1,2, Talita Guieiro Ribeiro Rocha1

and Mônica Cristina Oliveira1

,

interest, thereby allowing for a more precise delivery method [140].

, Elaine Amaral Leite3

Vales do Jequitinhonha e Mucuri, Diamantina, Minas Gerais, Brazil

delivery systems.

112 Cancer Treatment - Conventional and Innovative Approaches

treatment [140].

**Author details**

Sávia Caldeira de Araújo Lopes1

Gerais, Belo Horizonte, Minas Gerais, Brazil

Diêgo dos Santos Ferreira1

pirito Santo, Vitória, Brazil


[16] Torchilin VP, Omelyanenko VG, Papisov MI, Bogdanov AA Jr, Trubetskoy VS, Her‐ ron JN, Gentry CA. Poly(ethyleneglycol) on the liposome surface: on the mechanism of polymer-coated liposome longevity. Biochimica et Biophysica 1994;1195(1) 11-20.

not increase tumor localization but does increase internalization in animal models.

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 115

[29] Hatakeyama H, Akita H, Ishida E, Hashimoto K, Kobayashi H, Aoki T, Yasuda J, Ob‐ ata K, Kikuchi I, Ishida T, Kiwada H, Harashima H. Tumor targeting of doxorubicin by anti-MT1-MMP antibody-modified PEG liposomes. International Journal of Phar‐

[30] Xu L, Huang CC, Huang W, Tang WH, Rait A, Yin YZ, Cruz I, Xiang LM, Pirollo KF, Chang EH. Systemic tumor-targeted gene delivery by anti-transferrin receptor scFv-

[31] Xiong XB, Huang Y, Lü WL, Zhang X, Zhang H, Zhang Q. Preparation of doxorubi‐ cin-loaded stealth liposomes modified with RGD mimetic and cellular association in

[32] Li X, Ding L, Xu Y, Wang Y, Ping Q. Targeted delivery of doxorubicin using stealth liposomes modified with transferrin. International Journal of Pharmaceutics

[33] Paliwal SR, Paliwal R, Mishra N, Mehta A, Vyas SP. A novel cancer targeting ap‐ proach based on estrone anchored stealth liposome for site-specific breast cancer

[34] Yamada A, Taniguchi Y, Kawano K, Honda T, Hattori Y, Maitani Y. Design of folatelinked liposomal doxorubicin to its antitumor effect in mice. Clinical Cancer Re‐

[35] Lasch J., Weissing V., Brandl M. Preparation of liposomes. In: Torchilin VP., Weissig V. (2 ed) Liposomes: a pratical approach. New York: Oxford Universty Press; 2003,

[36] Bangham AD, Standish MM, Watkins JC. Diffusion of univalent ions the lamellae of

[37] Wagner A, Vorauer-Uhl K. Liposome technology for industrial purposes. Journal of

[38] Zuidam NJ, Gouw HK, Barenholz Y, Crommelin DJ. Physical (in) stability of lipo‐ somes upon chemical hydrolyxis: the role of lysophospholipids and fatty acids. Bio‐

[39] Swarbrick, J., Boylan, J.C. Liposome as Pharmaceutical Dosage Forms. In: Dekker M. Encyclopedia of Pharmaceutical Technology. New York:Oxford Universty Press;

[40] Edwards KA, Baeumner AJ. Analysis of liposomes. Talanta 2006;68(5) 1432–1441.

swollen phospholipids. Journal of Molecular Biology 1965;13(1) 238-252.

immunoliposomes. Mollecular Cancer Therapy 2002,1(5) 337–346.

vitro. Acta Pharmaceutica Sinica 2005;40(12) 1085-1990.

therapy. Current Cancer Drug Targets 2010;10(3) 343-353.

Drug Delivery 2011;2011 (Article ID 591325) 1-9.

chimica et Biophysica Acta 1995;1240(1) 101-110.

Cancer Research 2006;66(13) 6732-6740.

maceutics 2007;342(1-2) 194–200.

2009;373(1-2) 116-123.

search 2008;14(24) 8161-8168.

p3-27.

1994 p1-39


not increase tumor localization but does increase internalization in animal models. Cancer Research 2006;66(13) 6732-6740.

[29] Hatakeyama H, Akita H, Ishida E, Hashimoto K, Kobayashi H, Aoki T, Yasuda J, Ob‐ ata K, Kikuchi I, Ishida T, Kiwada H, Harashima H. Tumor targeting of doxorubicin by anti-MT1-MMP antibody-modified PEG liposomes. International Journal of Phar‐ maceutics 2007;342(1-2) 194–200.

[16] Torchilin VP, Omelyanenko VG, Papisov MI, Bogdanov AA Jr, Trubetskoy VS, Her‐ ron JN, Gentry CA. Poly(ethyleneglycol) on the liposome surface: on the mechanism of polymer-coated liposome longevity. Biochimica et Biophysica 1994;1195(1) 11-20.

[17] Zeisig R, Shimada K, Hirota S, Arndt D. Effect of sterical stabilization on macrophage uptake in vitro and on thickness of the fixed aqueous layer of liposomes made from

[18] Ulrich AS. Biophysical aspects of using liposomes as delivery vehicles. Bioscience Re‐

[19] Simões S, Moreira JN, Fonseca C, Düzgüneş N, de Lima MC. On the formulation of pH-sensitive liposomes with long circulation times. Advanced Drug Delivery Re‐

[20] Carvalho-Júnior AD, Vieira FP, Melo VJM, Lopes MTP, Silveira JN, Ramaldes GA, Garnier-Suillerot A, Pereira-Maia EC, Oliveira MC. Preparation and cytotoxicity of cisplatin loaded liposomes. Brazilian Journal of Medical and Biological Research

[21] Gulino PM, Grantham FH, Smith SH, Haggerty AC. Modification of the acid-basic status of the internal milieu of tumors. Journal of the National Cancer Institute

[22] Bergstrand N, Arfvidsson MC, Kim JM, Thompson DH, Edwards K. Interactions be‐ tween pH-sensitive liposomes and model membranes. Biophysical Chemistry

[23] Hong MS, Lim SJ, Oh YK, Kim CK. pH-sensitive, serum-stable and long-circulating liposomes as a new drug delivery system. Journal of Pharmacy and Pharmacology

[24] Wang M, Thanou M. Targeting nanoparticles to cancer. Pharmacological Research

[25] Sawant RR, Torchilin VP. Challenges in Development of Targeted Liposomal Thera‐

[26] Mamot C, Drummond DC, Noble CO, Kallab V, Guo Z, Hong K, Kirpotin DB, Park JW. Epidermal Growth Factor Receptor–Targeted Immunoliposomes Significantly Enhance the Efficacy of Multiple Anticancer Drugs In vivo. Cancer Research

[27] Sapra P, Allen TM. Improved outcome when B-cell lymphoma is treated with combi‐ nations of immunoliposomal anticancer drugs targeted to both the CD19 and CD20

[28] Kirpotin DB, Drummond DC, Shao Y, Shalaby MR, Hong K, Nielsen UB, Marks JD, Benz CC, Park JW. Antibody targeting of long-circulating lipidic nanoparticles does

alkylphosphocholines. Biochimica et Biophysica Acta 1996;1285(2) 237-45.

ports 2002;22(2) 129-150.

114 Cancer Treatment - Conventional and Innovative Approaches

views 2004;56(7) 947-965.

2007;40(8) 1149-1157.

1967;34(6) 857-869.

2003;104(1) 361-79.

2002;54(1) 51-58.

2010;62(2) 90-99.

2005;65(24) 11631-11638.

peutics. The AAPS Journal 2012;14(2) 303-315.

epitopes. Clinical Cancer Research 2004;10(7) 2530 – 2537.


[41] Plessis JD, Ramachandran C, Weiner N, Muller G. The influence of lipid composition and lamellarity of liposomes on the physical stability of liposomes upon storage. In‐ ternational Journal of Pharmaceutics 1996;127(2) 273-278.

[53] Crowe JH, Hoekstra FA, Nguyen KHN, Crowe LM. Is vitrification involved in de‐ pression of the phase transition temperature in dry phospholipids? Biochimica et Bi‐

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 117

[54] European Medicines Agency - EMA. Note for Guidance on the Pre-Clinical Evalua‐ tion of Anticancer Medicinal Products - CPMP/SWP/997/96. 1998; http:www.emea.europa.eu/pdfs/human/swp/099796en.pdf (accessed 06 May 2009).

[55] Mcelvany, KD. FDA Requirements for Preclinical Studies. Clinical Trials in the Neu‐

[56] Hofheinz RD, Gnad-Vogt SU, Beyer U, Hochhaus A. Liposomal encapsulated anti-

[57] Harrington KJ, Lewanski CR, Stewart JSW. Liposomes as vehicles for targeted thera‐ py of cancer. Part 1: preclinical development. Clinical Oncology (Royal College of Ra‐

[58] Harrington KJ, Lewanski CR, Stewart JSW. Liposomes as vehicles for targeted thera‐ py of cancer. Part 2: clinical development. Clinical Oncology (Royal College of Radi‐

[59] Ferrari, M. Cancer nanotechnology: opportunities and challenges. Nature Reviews

[60] Park, JW. Liposome-based drug delivery in breast cancer treatment. Breast Cancer

[61] Wong HL, Bendayan R, Rauth AM, Li Y, Wu XY. Chemotherapy with anticancer drugs encapsulated in solid lipid nanoparticles. Advanced Drug Delivery Reviews

[62] Wang X, Wang Y, Chen Z, Shin DM. Advances of Cancer Therapy by Nanotechnolo‐

[63] Kondagunta GV, Bacik J, Donadio A, Bajorin D, Marion S, Sheinfeld J, Bosl GJ, Mot‐ zer RJ. Combination of paclitaxel, ifosfamide and cisplatin is an effective second-line therapy for patients with relapsed testicular germ cell tumors. Journal of Clinical On‐

[64] Guillot T, Spielmann M, Kac J, Luboinski B, Tellez-Bernal E, Munck JN, Bachouchi M, Armand JP, Cvitkovic E. Neoadjuvant chemotherapy in multiple synchronous head and neck and esophagus squamous cell carcinomas. Laryngoscope 1992;102(3)

[65] Le Chevalier T, Brisgand D, Douillard JY, Pujol JL, Alberola V, Monnier A, Riviere A, Lianes P, Chomy P, Cigolari S. Randomized study of vinorelbine and cisplatin versus vindesine and cisplatin versus vinorelbine alone in advanced non-small-cell lung

ophysica Acta – Biomembranes 1996;1280(2) 187-196

cancer drugs. Anti-Cancer Drugs 2005;16(7) 691-707

diologists – Great Britain) 2000;12(1) 2–15.

ologists – Great Britain) 2000;12(1) 16–24.

gy. Cancer Research Treatment 2009;41(1) 1-11.

rosciences 2009;25 46–49.

Cancer 2005;5(3) 161-171.

Research 2002; 4(3)95-99

cology 2005;23(27) 6549-6555.

2007;59(6) 491-504.

311–319.


[53] Crowe JH, Hoekstra FA, Nguyen KHN, Crowe LM. Is vitrification involved in de‐ pression of the phase transition temperature in dry phospholipids? Biochimica et Bi‐ ophysica Acta – Biomembranes 1996;1280(2) 187-196

[41] Plessis JD, Ramachandran C, Weiner N, Muller G. The influence of lipid composition and lamellarity of liposomes on the physical stability of liposomes upon storage. In‐

[42] Abdelwahed W, Degobert G, Stainmesse S, Fessi H. Freeze-drying of nanoparticles: Formulation, process and storage considerations. Advanced Drug Delivery Reviews

[43] Chen C, Han D, Cai C. Tang, X. An overview of liposome lyophilization and its fu‐

[44] Zhang JA, Pawelchak J. Effect of pH, ionic strength and oxygen burden on the chemi‐ cal stability of EPC/cholesterol liposomes under accelerated conditions. Part 1: Lipid hydrolysis. European Journal of Pharmaceutics and Biopharmaceutics 2000;50(3)

[45] Abdelwahed W, Degobert G, Fessi H. Investigation of nanocapsules stabilization by

[46] Bendas G, Wilhen F, Nuhm P. Synthetic glycolipids as membrane bound cryoprotec‐ tants in the freeze-drying process of liposomes. European Journal of Pharmaceutical

[47] Mohammed AR, Bramwell VW, Coombes AGA, Perrie Y. Lyophilisation and sterili‐ sation of liposomal vaccines to produce stable and sterile products. Methods

[48] Santivarangkna C, Higl B, Foerst P. Protection mechanisms of sugars during differ‐ ent stages of preparation process of dried lactic acid starter cultures. Food Microbiol‐

[49] Diaz S, Amalfa F, De Lopez B, Disalvo EA. Effect of water polarized at the carbonyl groups of phosphatidylcholines on the dipole potential of lipid bilayers. Langmuir

[50] Luzardo MC, Amalfa F, Nunez AM, Diaz, S, De Lopez ACB, Disalvo EA. Effect of trehalose and sucrose on the hydration and dipole potential of lipid bilayers. Byo‐

[51] Villarreal MA, Diaz SB, Disalvo EA, Montich GG. Molecular dynamics simulation study of the interaction of trehalose with lipids membranes. Langmuir 2004;20(18)

[52] Koster KL, Lei YP, Anderson M, Martin S, Bryant, G. Effects of vitrified and nonvitri‐ fied sugars on phosphatidylcholine fluid-to-gel phase transitions. Byophysical Jour‐

amorphous excipients during freeze-drying and storage 2006;63(2) 87-94.

ternational Journal of Pharmaceutics 1996;127(2) 273-278.

ture potential. Journal of Controlled Release 2010;142(3) 299–311.

2006;58(15) 1688–1713.

116 Cancer Treatment - Conventional and Innovative Approaches

Sciences1996;4(4) 211-222.

2006;40(1) 30–38.

ogy 2008;25(3) 429-441.

1999;15(15) 5179-5182.

nal 2000;78(4) 1932–1946.

7844-7851.

physical Journal 2000;78(5) 2452-2458.

357-364.


cancer: results of a European multicenter trial including 612 patients. Journal of Clin‐ ical Oncology 1994;12(2) 360-367.

[76] Fedier A, Poyet C, Perucchini D, Boulikas T, Fink D. MLH1-deficient tumor cells are resistant to lipoplatin, but retain sensitivity to lipoxal. Anticancer Drugs. 2006;17(3)

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 119

[77] Boulikas T. Low toxicity and anticancer activity of a novel liposomal cisplatin (Lipo‐

[78] Devarajan P, Tarabishi R, Mishra J, Ma K, Kourvetaris A, Vougiouka M, Boulikas T. Low renal toxicity of Lipoplatin compared to cisplatin in animals. Anticancer Re‐

[79] Marr AK, Kurzman ID, Vail DM. Preclinical evaluation of a liposome-encapsulated formulation of cisplatin in clinically normal dogs. American Journal of Veterinary

[80] Boulikas T, Stathopoulos GP, Volakakis N, Vougiouka M. Systemic Lipoplatin infu‐ sion results in preferential tumor uptake in human studies. Anticancer Research

[81] Stathopoulos GP, Boulikas T, Vougiouka M, Rigatos SK, Stathopoulos JG. Liposomal cisplatin combined with gemcitabine in pretreated advanced pancreatic cancer pa‐

[82] Froudarakis ME, Pataka A, Pappas P, Anevlavis S, Argiana E, Nikolaidou M, Koulia‐ tis G, Pozova S, Marselos M, Bouros D. Phase 1 trial of lipoplatin and gemcitabine as a second-line chemotherapy in patients with nonsmall cell lung carcinoma. Cancer

[83] Stathopoulos GP, Rigatos SK, Stathopoulos J. Liposomal cisplatin dose escalation for determining the maximum tolerated dose and dose-limiting toxicity: a phase I study.

[84] Farhat FS, Temraz S, Kattan J, Ibrahim K, Bitar N, Haddad N, Jalloul R, Hatoum HA, Nsouli G, Shamseddine AI. A phase II study of lipoplatin (liposomal cisplatin)/vinor‐ elbine combination in HER-2/neu-negative metastatic breast cancer. Clinical Breast

[85] Mylonakis N, Athanasiou A, Ziras N, Angel J, Rapti A, Lampaki S, Politis N, Karani‐ kas C, Kosmas C. Phase II study of liposomal cisplatin (Lipoplatin) plus gemcitabine versus cisplatin plus gemcitabine as first line treatment in inoperable (stage IIIB/IV)

[86] Jehn CF, Boulikas T, Kourvetaris A, Possinger K, Lüftner D. Pharmacokinetics of lip‐ osomal cisplatin (lipoplatin) in combination with 5-FU in patients with advanced head and neck cancer: first results of a phase III study. Anticancer Research

[87] Jehn CF, Boulikas T, Kourvetaris A, Kofla G, Possinger K, Lüftner D. First safety and response results of a randomized phase III study with liposomal platin in the treat‐

non-small cell lung cancer. Lung Cancer 2010;68(2) 240-247.

tients: a phase I-II study. Oncology Reports 2006;15(5) 1201-1204.

platin) in mouse xenografts. Oncology Report 2004;12(1) 3-12.

315-323.

search, 2004; 24 (4) 2193-2200.

Research 2004;65(11) 1474-1478.

2005;25(4) 3031-3039.

2008;113(10) 2752-2760.

Cancer 2011;11(6) 384-389.

2007;27(1A) 471-475.

Anticancer Research 2010;30(4) 1317-1321.


[76] Fedier A, Poyet C, Perucchini D, Boulikas T, Fink D. MLH1-deficient tumor cells are resistant to lipoplatin, but retain sensitivity to lipoxal. Anticancer Drugs. 2006;17(3) 315-323.

cancer: results of a European multicenter trial including 612 patients. Journal of Clin‐

[66] Shirazi FH, Molepo JM, Stewart DJ, Ng CE, Raaphorst GP, Goel R. Cytotoxicity, ac‐ cumulation, and efflux of cisplatin and its metabolites in human ovarian carcinoma

[67] Muggia FM, Fojo T. Platinums: extending their therapeutic spectrum. Journal of Che‐

[68] Hirai M, Minematsu H, Hiramatsu Y, Kitagawa H, Otani T, Iwashita S, Kudoh T, Chen L, Li Y, Okada M, Salomon DS, Igarashi K, Chikuma M, Seno M. Novel and simple loading procedure of cisplatin into liposomes and targeting tumor endothelial

[69] Krieger M, Eckstein N, Schneider V, Koch M, Royer, HD, Jaehde U, Bendas G. Over‐ coming cisplatin resistance of ovarian cancer cells by targeted liposomes in vitro. In‐

[70] Steerenberg PA, Storm G, de Groot G, Claessen A, Bergers JJ, Franken MA, van Hoe‐ sel QG, Wubs KL, de Jong WH. Liposomes as drug carrier system for cis-diammine‐ dichloroplatinum (II). II. Antitumor activity in vivo, induction of drug resistance, nephrotoxicity and Pt distribution. Cancer Chemotherapy and Pharmacology

[71] Newman MS, Colbern GT, Working PK, Engbers C, Amantea MA. Comparative pharmacokinetics, tissue distribution, and therapeutic effectiveness of cisplatin en‐ capsulated in long-circulating, pegylated liposomes (SPI-077) in tumor-bearing mice.

[72] Vaage J, Donovan D, Wipff E, Abra R, Colbern G, Uster P, Working P. Therapy of a xenografted human colonic carcinoma using cisplatin or doxorubicin encapsulated in long-circulating pegylated stealth liposomes. International Journal of Cancer

[73] Meerum Terwogt JM, Groenewegen G, Pluim D, Maliepaard M, Tibben MM, Huis‐ man A, ten Bokkel Huinink WW, Schot M, Welbank H, Voest EE, Beijnen JH, Schell‐ ens JM. Phase I and pharmacokinetic study of SPI-77, a liposomal encapsulated dosage form of cisplatin. Cancer Chemotherapy and Pharmacology 2002;49(3)

[74] Stathopoulos GP, Boulikas T, Vougiouka M, Deliconstantinos G, Rigatos S, Darli E, Viliotou V and Stathopoulos JG. Pharmacokinetics and adverse reactions of a new liposomal cisplatin (Lipoplatin): phase I study. Oncology Reports 2005;13(4) 589-595.

[75] Arienti C, Tesei A, Ravaioli A, Ratta M, Carloni S, Mangianti S, Ulivi P, Nicoletti S, Amadori D, Zoli W. Activity of lipoplatin in tumor and in normal cells in vitro. Anti‐

cells. Toxicology and Applied Pharmacology 1996;140(2):211-218.

cells. International Journal of Pharmaceutics 2010;391(1-2) 274–283.

ternational Journal of Pharmaceutics 2010;389(1-2) 10-17.

Cancer Chemotherapy and Pharmacology 1999;43(1) 1-7.

ical Oncology 1994;12(2) 360-367.

118 Cancer Treatment - Conventional and Innovative Approaches

motherapy 2004;16 (Suppl 4) 77-82.

1988;21(4) 299-307.

1999;80(1) 134-137.

cancer Drugs. 2008;19(10) 983-990.

201-210.


ment of advanced squamous cell carcinoma of the head and neck (SCCHN). Anti‐ cancer Research 2008;28(6B) 3961-3964.

[97] Stathopoulos GP, Boulikas T, Kourvetaris A, Stathopoulos J. Liposomal oxaliplatin in the treatment of advanced cancer: a phase I study. Anticancer Research. 2006:26(2B)

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 121

[98] Boulikas P. Cancer Treatments. C.I. 424/450; 514/492; 424; 649 US, 3 mar. 2006, 26 feb.

[99] Boulikas T, Pantos A, Bellis E, Christofis P. Designing platinum compounds in can‐

[100] Leonard RCF, Williams S, Tulpule A, Levine AM, Oliveros S. Improving the thera‐ peutic index of anthracycline chemotherapy: Focus on liposomal doxorubicin (Myo‐

[101] Safra T. Cardiac safety of liposomal anthracyclines, The oncologist 2003;8(suppl 2)

[102] Harris L, Batist G, Belt R, Rovira D, Navari R, Azarnia N, Welles L, Winer E. Lipo‐ some-Encapsulated Doxorubicin Compared with Conventional Doxorubicin in a Randomized Multicenter Trial as First-Line Therapy of Metastatic Breast Carcinoma.

[103] Forssen EA, Coulter DM, Proffitt RT. Selective in vivo localisation of daunorubicin small unilamellar vesicles in solid tumours. Cancer Research 1992;52(12) 3255-3261.

[104] Forssen EA, Ross ME. DaunoxomeTM treatment of solid tumors: Preclinical and clin‐

[105] Pea F, Russo D, Michieli M, Baraldo M, Ermacora A, Damiani D, Baccarani M, Furla‐ nut M.Liposomal daunorubicin plasmatic and renal disposition in patients with

acute leukemia. Cancer Chemotherapy and Pharmacology 2000;46(4) 279-286.

[106] Gill PS, Espina BM, Muggia F, Cabriales S, Tulpule A, Esplin JA, Liebman HA, For‐ ssen E, Ross ME, Levine AM. Phase I/II clinical and pharmacokinetic evaluation of

[107] Gill PS, Wernz J, Scadden DT, Cohen P, Mukwaya GM, Von Roenn JH, Jacobs M, Kempin S, Silverberg I, Gonzales G, Rarick MU, Myers AM, Shepherd F, Sawka C, Pike MC, Ross ME. Randomized phase III trial of liposomal daunorubicin versus doxorubicin, bleomycin, and vincristine in AIDS-related Kaposi's sarcoma. Journal of

[108] Rosenthal E, Poizot-Martin I, Saint-Marc T, Spano JP, Cacoub P. Phase IV study of liposomal daunorubicin (DaunoXome) in AIDS-related Kaposi sarcoma. American

[109] Kanter PM, Bullard GA, Pilkiewicz FG, Mayer LD, Cullis PR, Pavelic ZP. Preclinical toxicology study of liposome encapsulated doxorubicin (TLC D-99): comparison with doxorubicin and empty liposomes in mice and dogs. In Vivo 1993;7(1):85-95.

liposomal daunorubicin. Journal of Clinical Oncology 1995;13(4) 996-1003.

ical investigations, Journal of Liposome Research 1994;4(1) 481–512.

cer: structures and mechanisms. Cancer Therapy 2007;5 537-583.

cet®). The Breast 2009;18(4) 218–224.

Clinical Oncology 1996;14(8) 2353-2364.

Journal of Clinical Oncology 2002;25(1) 57-59.

Cancer 2002;94(1) 25-36.

1489-93.

2009.

17-24.


[97] Stathopoulos GP, Boulikas T, Kourvetaris A, Stathopoulos J. Liposomal oxaliplatin in the treatment of advanced cancer: a phase I study. Anticancer Research. 2006:26(2B) 1489-93.

ment of advanced squamous cell carcinoma of the head and neck (SCCHN). Anti‐

[88] Stathopoulos GP, Antoniu D, Dimitroulis J, Michalopoulou P, Bastas A, Marosis K, Stathopoulos J, Provata A, Yiamboudakis P, Veldekis D, Lolis N, Georgatou N, Tou‐ bis M, Pappas Ch, Tsoukalas G. Liposomal cisplatin combined with paclitaxel versus cisplatin and paclitaxel in non-small-cell lung cancer: a randomized phase III multi‐

[89] Stathopoulos GP, Boulikas T. Lipoplatin formulation review article. Journal of Drug

[90] Júnior ADC, Mota LG, Nunan EA, Wainstein AJA, Wainstein APDL, Leal AL, Cardo‐ so VN, Oliveira MC. Tissue distribution evaluation of stealth pH-sensitive liposomal cisplatin versus free cisplatin in Erlich tumor-bearing mice. Life Sciences 2007;80(7)

[91] Chauffert B, Favoulet P, Polycarpe E, Duvillard C, Beltramo JL, Bichat F, Rat P, Genne P, Benoit L. Rationale supporting the use of vasoconstrictors for intraperito‐ neal chemotherapy with platinum derivatives. Surgeon Oncology Clinics of North

[92] Araújo JG, Mota LG, Leite EA, Maroni Lde C, Wainstein AJ, Coelho LG, Savassi-Ro‐ cha PR, Pereira MT, de Carvalho AT, Cardoso VN, De Oliveira MC. Biodistribution and antitumoral effect of long-circulating and pH-sensitive liposomal cisplatin ad‐ ministered in Ehrlich tumor-bearing mice. Experimental Biology and Medicine (May‐

[93] Leite EA, Giuberti CS, Wainstein AJ, Wainstein AP, Coelho LG, Lana AM, Savassi-Rocha PR, De Oliveira MC. Acute toxicity of long-circulating and pH-sensitive lipo‐ somes containing cisplatin in mice after intraperitoneal administration. Life Sciences

[94] Leite EA, Lana AM, Junior AD, Coelho LG, De Oliveira MC. Acute toxicity study of cisplatin loaded long-circulating and pH-sensitive liposomes administered in mice.

[95] Leite EA. Avaliação da Toxicidade Aguda e Atividade Antitumoral de Lipossomas pH-sensíveis de circulação prolongada contendo cisplatina. PhD Thesis. Universi‐

[96] Maroni, LC, Silveira ACO, Leite EA, Melo MM, Ribeiro AFC, Cassali GD, Souza CM, Fagundes EMS, Caldas IR, Araújo MSS, Filho OAM, Oliveira MC, Carvalho AT. An‐ titumor effectiveness and toxicity of cisplatin loaded long-circulating and pH-sensi‐ tive liposomes against Ehrlich ascitic tumor. Experimental Biology and Medicine

Journal of Biomedical Nanotechnology 2012;8(2) 229-239.

cancer Research 2008;28(6B) 3961-3964.

120 Cancer Treatment - Conventional and Innovative Approaches

Delivery 2012;2012 581363.

America 2003;12:835–48.

wood) 2011;236(7) 808-815.

2009;84(19-20) 641-649.

dade Federal de Minas Gerais; 2010.

2012;DOI:10.1258/ebm.2012.011432.

659-664.

center trial. Annals of Oncology 2010;21(11) 2227-2232.


[110] Harasym TO, Cullis PR, Bally MB. Intratumour distribution of doxorubicin following i.v. administration of drug encapsulated in egg phosphatidylcholine/cholesterol lipo‐ somes. Cancer Chemotherapy and Pharmacology 1997;40(4) 309–317.

[122] Zhang JA, Anyarambhatla G, Ma L, Ugwu S, Xuan T, Sardone T, Ahmad I. Develop‐ ment and characterisation of a novel Cremophor EL free liposome based paclitaxel (LEP-ETU) formulation. European Journal of Pharmaceutics and Biopharmaceutics

Liposomes as Carriers of Anticancer Drugs http://dx.doi.org/10.5772/55290 123

[123] Yang T, Cui FD, Choi MK, Cho JW, Chung SJ, Shim CK, Kim DD. Enhanced solubili‐ ty and stability of PEGylated liposomal paclitaxel: In vitro and in vivo evaluation. In‐

[124] Strieth S, Eichhirn ME, Werner A, Sauer B, Teifeil M, Michaelis U, Berghaus A, Delli‐ an M. Paclitaxel encapsulated in cationic liposomes increases tumor microvessel leakiness and improves therapeutic efficacy in combination with cisplatin. Clinical

[125] Glantz MJ, Lafollette S, Jaeckle KA, Shapiro W, Swinnen L, Rozental JR, Phuphanich S, Rogers LR, Gutheil JC, Batchelor T, Lyter D, Chamberlain M, Maria BL, Schiffer C, Bashir R, Thomas D, Cowens W, Howell SB. Randomized trial of a slow-release ver‐ sus a standard formulation of cytarabine for the intrathecal treatment of lymphoma‐

[126] Glantz MJ, Jaeckle KA, Chamberlain MC, Phuphanich S, Recht L, Swinnen LJ, Maria B, Lafollette S, Schumann GB, Cole BF, Howell SB. A randomized controlled trial comparing intrathecal sustained release cytarabine (DepoCyte) to intrathecal metho‐ trexate in patients with neoplastic meningitis from solid tumours. Clinical Cancer Re‐

[127] Spina M, Chimienti E, Martellotta F, Vaccher E, Berretta M, Zanet E, Lleshi A, Canzo‐ nieri V, Bulian P, Tirelli U. Phase 2 study of intrathecal, long-acting liposomal cytara‐ bine in the prophylaxis of lymphomatous meningitis in human immunodeficiency

[128] Rodriguez MA, Pytlik R, Kozak T, Chhanabhai M, Gascoyne R, Lu B, Deitcher SR, Winter JN. Vincristine sulfate liposomes injection (Marqibo) in heavily pretreated pa‐ tients with refractory aggressive non-Hodgkin lymphoma: report of the pivotal

[129] Sapra P, Allen TM. Ligand-targeted liposomal anticancer drugs. Progress in Lipid

[130] Low PS, Kularatne SA. Folate-targeted therapeutic and imaging agents for cancer.

[131] Takeuchi H, Kojima H, Toyoda T, Yamamoto H, Hino T, Kawashima Y. Prolonged circulation time of doxorubicin-loaded liposomes coated with amodified polyvinyl alcohol after intravenous injection in rats. European Journal of Pharmaceutics and Bi‐

virus-related non-Hodgkin lymphoma. Cancer 2010; 116(6) 1495-1501.

tous meningitis. Journal of Clinical Oncology 1999;17(10) 3110–3116.

ternational Journal of Pharmaceutics 2007; 338(1-2) 317–326.

Cancer Research 2008; 14(14) 4603-4611.

search 1999;5(11) 3394–3402.

Research 2003; 42(5) 439–462.

opharmaceutics 1999; 48(2)123–129.

phase 2 study. Cancer 2009; 115(15) 3475-3482.

Current Opinion in Chemical Biology 2009; 13(3) 256–262.

2005;59(1) 177-187.


[122] Zhang JA, Anyarambhatla G, Ma L, Ugwu S, Xuan T, Sardone T, Ahmad I. Develop‐ ment and characterisation of a novel Cremophor EL free liposome based paclitaxel (LEP-ETU) formulation. European Journal of Pharmaceutics and Biopharmaceutics 2005;59(1) 177-187.

[110] Harasym TO, Cullis PR, Bally MB. Intratumour distribution of doxorubicin following i.v. administration of drug encapsulated in egg phosphatidylcholine/cholesterol lipo‐

[111] Cowens JW, Creaven PJ, Greco WR, Brenner DE, Tung Y, Ostro M, Pilkiewicz F, Ginsberg R, Petrelli N. Initial clinical (phase I) trial of TLC D-99 (doxorubicin encap‐

[112] Batist G, Ramakrishnan G, Rao CS, Chandrasekharan A, Gutheil J, Guthrie T, Shah P, Khojasteh A, Nair MK, Hoelzer K, Tkaczuk K, Park YC, Lee LW. Reduced cardiotox‐ icity and preserved antitumor efficacy of liposome-encapsulated doxorubicin and cy‐ clophosphamide compared with conventional doxorubicin and cyclophosphamide in a randomized, multicenter trial of metastatic breast cancer. Journal of Clinical Oncol‐

[113] Vaage J, Donovan D, Mayhew E, Uster P, Woodle M. Therapy of mouse mammary carcinomas with vincristine and doxorubicin encapsulated in sterically stabilized lip‐

[114] Vaage J, Donovan D, Mayhew E, Abra R, Huang A. Therapy of human ovarian carci‐ noma xenografts using doxorubicin encapsulated in sterically stabilized liposomes.

[115] Gabizon A, Shmeeda H, Barenholz Y. Pharmacokinetics of pegylated liposomal dox‐

[116] Krown SE, Northfelt DW, Osoba D, Stewart JS. Use of liposomal anthracyclines in

[117] Rose PG. Pegylated liposomal doxorubicin: optimizing the dosing schedule in ovari‐

[118] Hussein MA, Anderson KC. Role of liposomal anthracyclines in the treatment of multiple myeloma. Seminars in Oncology 2004; 31(6 Supplement 13) 147–160.

[119] Robert NJ, Vogel CL, Henderson IC, Sparano JA, Moore MR, Silverman P, Overmoy‐ er BA, Shapiro CL, Park JW, Colbern GT, Winer EP, Gabizon AA. The role of the lip‐ osomal anthracyclines and other systemic therapies in the management of advanced

[120] Hau P, Fabel K, Baumgart U, Rümmele P, Grauer O, Bock A, Dietmaier C, Dietmaier W, Dietrich J, Dudel C, Hübner F, Jauch T, Drechsel E, Kleiter I, Wismeth C, Zellner A, Brawanski A, Steinbrecher A, Marienhagen J, Bogdahn U. Pegylated liposomal doxorubicin efficacy in patients with recurrent high-grade glioma. Cancer

[121] Zhang Q, Huang XE, Gao LL. A clinical study on the premedication of paclitaxel lip‐ osome in the treatment of solid tumors. Biomedicine & Pharmacotherapy 2009; 63(8)

Kaposi's sarcoma. Seminars in Oncology 2004;31(6 Suppl 13) 36-52.

breast cancer. Seminars in Oncology 2004;31(6 Suppl 13) 106-146.

somes. Cancer Chemotherapy and Pharmacology 1997;40(4) 309–317.

sulated in liposomes). Cancer Research 1993;53(12) 2796-2802.

osomes. International Journal of Cancer 1993;54(6) 959-964.

orubicin. Clinical Pharmacokinetic 2003;42(5) 419-436.

an cancer. Oncologist 2005;10(3) 205-214.

ogy 2001;19(5) 1444-1454.

122 Cancer Treatment - Conventional and Innovative Approaches

Cancer 1993;72(12) 3671-3675.

2004;100(6) 1199–207.

603-607.


[132] Li X, Ding L, Xu Y, Wang Y, Ping Q. Targeted delivery of doxorubicin using stealth liposomes modified with transferring. International Journal of Pharmaceutics 2009; 373(1-2) 116-23.

**Section 2**

**Combinatorial Strategies to Fight Cancer:**

**Surgery, Radiotherpay, Backytherapy,**

**Chemotherapy, and Hyperthermia**


**Combinatorial Strategies to Fight Cancer: Surgery, Radiotherpay, Backytherapy, Chemotherapy, and Hyperthermia**

[132] Li X, Ding L, Xu Y, Wang Y, Ping Q. Targeted delivery of doxorubicin using stealth liposomes modified with transferring. International Journal of Pharmaceutics 2009;

[133] Song CK, Jung SH, Kim DD, Jeong KS, Shin BC, Seong, H. Disaccharide-modified lip‐ osomes and their in vitro intracellular uptake. International Journal of Pharmaceutics

[134] Pan XQ, Lee RJ. In vivo antitumor activity of folate receptor-targeted liposomal dau‐ norubicin in a murine leukemia model. Anticancer Research 2005;25(1A) 343-346.

[135] Shmeeda H, Mak L, Tzemach D, Astrahan P, Tarshish M, Gabizon A. Intracellular uptake and intracavitary targeting of folate-conjugated liposomes in a mouse lym‐ phoma model with up-regulated folate receptors. Molecular Cancer Therapeutics

[136] Kim KS, Lee YK, Kim JS, Koo KH, Hong HJ, Park YS. Targeted gene therapy of LS174 T human colon carcinoma by anti-TAG-72 immunoliposomes. Cancer Gene Therapy

[137] Schnyder A, Huwyler J. Drug transport to brain with targeted liposomes. NeuroRx: The Journal of the American Society for Experimental NeuroTherapeutics 2005;2(1)

[138] Huwyler J, Drewe J, Krähenbühl S. Tumor targeting using liposomal antineoplastic

[139] Ruenraroengsak P, Cook JM, Florence AT. Nanosystem drug targeting: Facing up to

[140] Cukierman E, Khan DR. The benefits and challenges associated with the use of drug delivery systems in cancer therapy. Biochemical Pharmacology 2010; 80(5) 762-70.

drugs. International Journal of Nanomedicine 2008;3(1) 21–29.

complex realities. Journal of Controlled Release 2010; 141(3) 265–276.

373(1-2) 116-23.

2009; 380(1-2) 161–169.

124 Cancer Treatment - Conventional and Innovative Approaches

2006;5(4) 818-824.

2008;15(5) 331-340.

99-107.

**Chapter 5**

**The Role of Surgery in**

http://dx.doi.org/10.5772/55341

effect of long-term viral damage [8-9].

a great impact on any therapeutic decision.

**1. Introduction**

Georgios Tsoulfas and Polyxeni Agorastou

Additional information is available at the end of the chapter

**the Treatment of Hepatocellular Carcinoma**

Hepatocellular carcinoma (HCC) is the sixth most common cancer world-wide with approxi‐ mately 700,000 new cases a year, with increasing numbers in Europe and the United States [1]. The various risk factors are reflected in the worldwide heterogeneous incidence. The majority of cases of HCC develop in eastern Asia and sub-Saharan Africa due to chronic infection with hepatitis B virus (HBV), as well as aflatoxin. In other parts of the world such as Northern America, Europe and Japan, the prevailing risk factor is chronic infection with hepatitis C virus (HCV) and alcohol use [2]. Additional or synergistic factors include non-alcoholic steatohe‐ patitis (NASH), diabetes, obesity and tobacco, with their high prevalence in Northern America

offering a partial explanation for the continuously increasing incidence of HCC [3-6].

HCC develops in cirrhotic livers in 80% of cases, as cirrhosis is one of the strongest risk factors given its role as a preneoplastic condition [7]. The mechanism itself is not fully known, although it may be secondary to the disorderly architectural changes seen in the hepatic parenchyma of the cirrhotic liver providing a signal for malignant transformation. Addition‐ ally, there could be a role for DNA damage caused by viral integration, as incidence of HCC increases with viral load and duration of infection, thus raising the possibility of a cumulative

There has been major progress in understanding the nature of the disease, as well as the available therapies. Although the full range of treatment options has increased over time, especially with the advent of new surgical and molecular technologies, the mainstay of treatment remains surgery, as the only truly therapeutic option. This chapter will discuss the evaluation of the patient with HCC, the two main surgical treatments, liver resection and orthotopic liver transplantation (OLT), as well as future prospects which include the molecular classification of HCC and the efforts for targeted molecular therapies, which in turn will have

and reproduction in any medium, provided the original work is properly cited.

© 2013 Tsoulfas and Agorastou; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

### **Chapter 5**

### **The Role of Surgery in the Treatment of Hepatocellular Carcinoma**

Georgios Tsoulfas and Polyxeni Agorastou

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/55341

### **1. Introduction**

Hepatocellular carcinoma (HCC) is the sixth most common cancer world-wide with approxi‐ mately 700,000 new cases a year, with increasing numbers in Europe and the United States [1]. The various risk factors are reflected in the worldwide heterogeneous incidence. The majority of cases of HCC develop in eastern Asia and sub-Saharan Africa due to chronic infection with hepatitis B virus (HBV), as well as aflatoxin. In other parts of the world such as Northern America, Europe and Japan, the prevailing risk factor is chronic infection with hepatitis C virus (HCV) and alcohol use [2]. Additional or synergistic factors include non-alcoholic steatohe‐ patitis (NASH), diabetes, obesity and tobacco, with their high prevalence in Northern America offering a partial explanation for the continuously increasing incidence of HCC [3-6].

HCC develops in cirrhotic livers in 80% of cases, as cirrhosis is one of the strongest risk factors given its role as a preneoplastic condition [7]. The mechanism itself is not fully known, although it may be secondary to the disorderly architectural changes seen in the hepatic parenchyma of the cirrhotic liver providing a signal for malignant transformation. Addition‐ ally, there could be a role for DNA damage caused by viral integration, as incidence of HCC increases with viral load and duration of infection, thus raising the possibility of a cumulative effect of long-term viral damage [8-9].

There has been major progress in understanding the nature of the disease, as well as the available therapies. Although the full range of treatment options has increased over time, especially with the advent of new surgical and molecular technologies, the mainstay of treatment remains surgery, as the only truly therapeutic option. This chapter will discuss the evaluation of the patient with HCC, the two main surgical treatments, liver resection and orthotopic liver transplantation (OLT), as well as future prospects which include the molecular classification of HCC and the efforts for targeted molecular therapies, which in turn will have a great impact on any therapeutic decision.

© 2013 Tsoulfas and Agorastou; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

### **2. Evaluation of patients with hepatocellular carcinoma**

In order for surgical treatment for HCC to be successful, patients need to be chosen very carefully. It is essential that the evaluation, selection and treatment are performed by multi‐ disciplinary teams that include hepatologists, surgeons, oncologists, radiologists, pathologists and anesthesiologists. The reason is that we have to remember that we are dealing with more than one problem in the same setting. Specifically, the patient's HCC needs to be addressed, but it has to be done in the setting of the possible cirrhosis. The degree that the patient's liver function is affected can have a direct impact on several other organ systems (cardiopulmonary, renal) and thus directly influence any therapeutic decisions. It is interesting that, in contrast to several other cancers, there are not many randomized controlled trials to compare the treatments seen as curative for HCC, something which underscores the need for these patients to be followed in protocols whenever possible, so that evidence-based decisions can be made. Integrated Staging score, which combines the Child-Turcotte-Pugh (CTP) classification with

The Role of Surgery in the Treatment of Hepatocellular Carcinoma

http://dx.doi.org/10.5772/55341

129

The most widely accepted system appears to be the Barcelona Clinic Liver Cancer (BCLC) system, which was introduced in 1999 as an attempt to improve on the Okuda system, so as to include the functional aspect of the disease. It was developed based on a combination of data from a variety of studies looking into different types of treatment for different stages of the disease [14-16]. The BCLC takes into account the total cancer load, the stage of the cirrhosis and the patient's functional status, in an effort to determine the type of treatment necessary and the expected survival (Figure 1). It is the staging system most widely (but not universally) accepted, as it has been externally validated and it offers a pathway between staging and the different treatment modalities with an estimation of life expectancy [17]. It provides suggested treatments for the different stages of the disease, including early stage HCC where the aim is a cure, as opposed to advanced HCC where palliative treatments are proposed. In addition to providing proper patient care, universally-accepted staging for HCC is critical in allowing the comparison between results from different studies in order to draw the appropriate conclu‐ sions. A system such as the BCLC, which is a clinical system with predictive abilities, can offer a solid platform for the initial staging. Other systems, such as the simplified TNM, which includes pathological findings such as microvascular invasion, can be of more value in those

the simplified TNM system by the Liver Cancer Study Group of Japan (LCSGJ) [13].

patients undergoing resection or OLT.

**Figure 1.**

The first question that has to answered is whether the patient is an operative candidate, meaning whether the patient is in a position to undergo a major surgery from the standpoint of his overall health. It is essential that this evaluation is performed by physicians who are intimately aware of the challenges of liver resection or transplantation. For example, the anesthesiologist has to be aware that this will be an operation with potential significant blood loss and periods of hypotension, all of which will stress the cardiovascular system. This should help determine the kind of preoperative testing that is needed, although there is to-date no universally agreed upon preoperative protocol for patients undergoing liver resection. The importance of this can be seen even more clearly if we consider that given the improvements in surveillance and surgical technique and the general ageing of the population, older patients belonging to a higher risk group are being increasingly evaluated for liver surgery. Once the question of the patient as an operative candidate has been answered satisfactorily, the next one is whether the HCC is resectable. The answer to this question depends on identifying the stage of the disease, as well as the hepatic reserve of the patient.

#### **2.1. Staging of patients with hepatocellular carcinoma**

Regarding the stage, there is a lack of a common language as there is no consensus on a universal staging system. There are different ones, each one taking slightly different aspects of the disease into consideration. Some depend on clinical and radiological findings prior to the treatment, whereas others are based on the histopathological findings. Ideally, clinicallyapplicable staging for HCC should assess the tumor stage, the underlying liver function and the patient's biological status. Some of the staging systems, such as The American Joint Committee on Cancer/Union Internationale Contre le Cancer Tumor-Node-Metastasis staging system (AJCC/UICC TNM) stratifying patients into prognostic groups, are best suited to only patients undergoing resection or transplantation, without taking into consideration the underlying liver disease [10]. In an effort to consider tumor features and hepatic function, the Okuda system and the Cancer of the Liver Italian Program (CLIP) classifications were proposed [11-12]. Both of them have the ability to identify end stage disease but are not as accurate with early stage disease. A step towards solving this problem has been the Japan Integrated Staging score, which combines the Child-Turcotte-Pugh (CTP) classification with the simplified TNM system by the Liver Cancer Study Group of Japan (LCSGJ) [13].

The most widely accepted system appears to be the Barcelona Clinic Liver Cancer (BCLC) system, which was introduced in 1999 as an attempt to improve on the Okuda system, so as to include the functional aspect of the disease. It was developed based on a combination of data from a variety of studies looking into different types of treatment for different stages of the disease [14-16]. The BCLC takes into account the total cancer load, the stage of the cirrhosis and the patient's functional status, in an effort to determine the type of treatment necessary and the expected survival (Figure 1). It is the staging system most widely (but not universally) accepted, as it has been externally validated and it offers a pathway between staging and the different treatment modalities with an estimation of life expectancy [17]. It provides suggested treatments for the different stages of the disease, including early stage HCC where the aim is a cure, as opposed to advanced HCC where palliative treatments are proposed. In addition to providing proper patient care, universally-accepted staging for HCC is critical in allowing the comparison between results from different studies in order to draw the appropriate conclu‐ sions. A system such as the BCLC, which is a clinical system with predictive abilities, can offer a solid platform for the initial staging. Other systems, such as the simplified TNM, which includes pathological findings such as microvascular invasion, can be of more value in those patients undergoing resection or OLT.

**Figure 1.**

**2. Evaluation of patients with hepatocellular carcinoma**

128 Cancer Treatment - Conventional and Innovative Approaches

stage of the disease, as well as the hepatic reserve of the patient.

**2.1. Staging of patients with hepatocellular carcinoma**

In order for surgical treatment for HCC to be successful, patients need to be chosen very carefully. It is essential that the evaluation, selection and treatment are performed by multi‐ disciplinary teams that include hepatologists, surgeons, oncologists, radiologists, pathologists and anesthesiologists. The reason is that we have to remember that we are dealing with more than one problem in the same setting. Specifically, the patient's HCC needs to be addressed, but it has to be done in the setting of the possible cirrhosis. The degree that the patient's liver function is affected can have a direct impact on several other organ systems (cardiopulmonary, renal) and thus directly influence any therapeutic decisions. It is interesting that, in contrast to several other cancers, there are not many randomized controlled trials to compare the treatments seen as curative for HCC, something which underscores the need for these patients to be followed in protocols whenever possible, so that evidence-based decisions can be made.

The first question that has to answered is whether the patient is an operative candidate, meaning whether the patient is in a position to undergo a major surgery from the standpoint of his overall health. It is essential that this evaluation is performed by physicians who are intimately aware of the challenges of liver resection or transplantation. For example, the anesthesiologist has to be aware that this will be an operation with potential significant blood loss and periods of hypotension, all of which will stress the cardiovascular system. This should help determine the kind of preoperative testing that is needed, although there is to-date no universally agreed upon preoperative protocol for patients undergoing liver resection. The importance of this can be seen even more clearly if we consider that given the improvements in surveillance and surgical technique and the general ageing of the population, older patients belonging to a higher risk group are being increasingly evaluated for liver surgery. Once the question of the patient as an operative candidate has been answered satisfactorily, the next one is whether the HCC is resectable. The answer to this question depends on identifying the

Regarding the stage, there is a lack of a common language as there is no consensus on a universal staging system. There are different ones, each one taking slightly different aspects of the disease into consideration. Some depend on clinical and radiological findings prior to the treatment, whereas others are based on the histopathological findings. Ideally, clinicallyapplicable staging for HCC should assess the tumor stage, the underlying liver function and the patient's biological status. Some of the staging systems, such as The American Joint Committee on Cancer/Union Internationale Contre le Cancer Tumor-Node-Metastasis staging system (AJCC/UICC TNM) stratifying patients into prognostic groups, are best suited to only patients undergoing resection or transplantation, without taking into consideration the underlying liver disease [10]. In an effort to consider tumor features and hepatic function, the Okuda system and the Cancer of the Liver Italian Program (CLIP) classifications were proposed [11-12]. Both of them have the ability to identify end stage disease but are not as accurate with early stage disease. A step towards solving this problem has been the Japan

### **2.2. Evaluation of hepatic reserve of patients with hepatocellular carcinoma**

As far as evaluating the hepatic reserve of the patient is concerned, that is a determination of both quantity and quality. This is a major change from the past when there were multiple exclusion criteria, as the only ones that have been consistently validated over time are the postoperative remnant liver volume and hepatic function [18-20]. It has been shown that if 3 or more hepatic segments are left behind after a resection, or an adequate hepatic remnant, which is 25% for a normal liver and 40% for a cirrhotic one, then postoperative liver dysfunction can be avoided [21-22]. This means that it is essential to be able to accurately estimate the liver remnant and the future remaining liver volume preoperatively, especially in the case of extended resections. The most reliable way to do this has been CT volumetry, which with the advent of the Digital Imaging and Communications in Medicine (DICOM) standard has enabled volumetry to be performed even by the surgeon on a personal computer. Quality can be assessed either directly (liver biopsy) or indirectly, through assessment of the synthetic function of the liver (INR, platelets, albumin) or other marks of portal hypertension and cirrhosis, such as esophagogastroduodenoscopy (EGD) looking for varices. The underlying chronic liver disease, including its duration and whether the patient has received any treat‐ ment, are also important pieces of information.

a high-risk one [28]. The best candidates for liver resection, and those who could achieve 5-year survivals of up to 70%, are those patients with single lesion, asymptomatic HCC, and most importantly with preserved liver function [29-31]. The definition of preserved liver function includes the absence of clinically significant portal hypertension (hepatic vein wedge pressure difference less than 10mmHg, absence of varices or splenomegaly, and

portal hypertension, 5-year survival after resection goes down to 50%, whereas in those with combined portal hypertension and increased bilirubin levels it can be as low as 25% [33]. In order to predict the risk of postoperative hepatic insufficiency other groups have used the Model for End-stage Liver Disease (MELD) score, which is based on the values of the patient's creatinine, bilirubin and prothrombin time. Several studies have shown that when the MELD score is 9 or less, then hepatic resection can be safe with almost mini‐

The preference for patients with a single lesion has to do with the fact that in most cases multifocal HCC is associated with decreased survival and increased recurrence, potentially as an indication of already existing intrahepatic metastases. Although not prohibitive for resection, the presence of multiple lesions should alert the surgeon to the possibility of using treatments such as radiofrequency ablation and chemoembolization in combination with resection to obtain optimal results. Similar to multifocality, an increased tumor size is not necessarily prohibitive, but can serve as an indication of possible vascular invasion, which can in turn negatively affect the prognosis. When all of this is considered, the percentage of patients that can undergo hepatic resection under ideal conditions is less than 10%. However, even in this group of patients with cirrhosis, it is possible to achieve moderate long-term results [36-38].

When considering liver resection for HCC apart from the main question of the presence or absence of cirrhosis, there are other key issues to be addressed, such as ways to increase resectability, the differences between anatomic and non-anatomic resection and the use of

In an effort to treat large HCC with hepatic resection or in those patients with inade‐ quate liver remnant, there are certain preoperative manoeuvres that can help increase resectability in these challenging patients. Preoperative portal vein embolization (PVE) was introduced in 1986 by Kinoshita to prevent postoperative hepatic insufficiency, whereas Makuuchi had first introduced the concept to clinical practice in 1982 for the treatment of hepatic cholangiocarcinoma [39-40]. The main principle is to occlude the portal venous flow to the side of the tumor, and cause ipsilateral atrophy and, more importantly, contralater‐ al hypertrophy of the part of the liver that will be the future remnant after the resection. This can lead to an increase in the future remnant by about 20-40% within 4-6 weeks, thus potentially increasing the pool of candidates for resection [41-43]. Although there are no absolute contraindications, especially as experience with the procedure continues to grow,

mal chances of postoperative patient destabilization [33-35].

) and normal bilirubin values [32]. In patients with significant

The Role of Surgery in the Treatment of Hepatocellular Carcinoma

http://dx.doi.org/10.5772/55341

131

platelets over 100,000/mm3

**3.1. Considerations in liver resection**

laparoscopic surgery among others.

*3.1.1. The role of portal vein embolization*

By fully evaluating the patient with HCC, one can proceed more safely into determining whether the patient is a candidate for surgical treatment and which one: resection versus transplantation. Frequently, it may be necessary for the patient to be evaluated for both, as a patient undergoing a liver resection could show signs of hepatic failure postoperatively, leading to a discussion of whether transplantation is an option. It is wise for these decisions to be made beforehand, rather than during emotionally-charged times.

### **3. Hepatectomy**

The first question one has to consider when discussing the issue of hepatic resection for HCC is the presence or not of cirrhosis. In non-cirrhotic patients, hepatic resection represents the preferred treatment, as the lack of cirrhosis means that the patient can tolerate even an extended resection, and the non-cirrhotic liver will allow future re-resection, although it has a lower chance of de novo recurrence. Unfortunately, these patients without cirrhosis represent only 5% of cases in the West [23]. Even so, in these patients without cirrhosis, surgical resection for HCC can lead to 3-year survival of 46-76% and 5-year survivals of 30-50%, depending on the selection criteria and on whether fibrolamellar HCC cases are included in the study [24-26]. A high recurrence rate at 5 years of around 60% remains, even after potentially curative resections, possibly owing to intrahepatic metastases rather than existing disease, as the effect of the underlying chronic liver disease and the cirrhosis is not present [27].

In patients with cirrhosis, using proper selection criteria to avoid postoperative hepatic failure is critical. That set of criteria was originally based on the Child-Pugh classifica‐ tion, which however was not shown to have a consistent predictive value, as patients may show signs of hepatic dysfunction even at a stage of Child-Pugh A, thus making a resection

a high-risk one [28]. The best candidates for liver resection, and those who could achieve 5-year survivals of up to 70%, are those patients with single lesion, asymptomatic HCC, and most importantly with preserved liver function [29-31]. The definition of preserved liver function includes the absence of clinically significant portal hypertension (hepatic vein wedge pressure difference less than 10mmHg, absence of varices or splenomegaly, and platelets over 100,000/mm3 ) and normal bilirubin values [32]. In patients with significant portal hypertension, 5-year survival after resection goes down to 50%, whereas in those with combined portal hypertension and increased bilirubin levels it can be as low as 25% [33]. In order to predict the risk of postoperative hepatic insufficiency other groups have used the Model for End-stage Liver Disease (MELD) score, which is based on the values of the patient's creatinine, bilirubin and prothrombin time. Several studies have shown that when the MELD score is 9 or less, then hepatic resection can be safe with almost mini‐ mal chances of postoperative patient destabilization [33-35].

The preference for patients with a single lesion has to do with the fact that in most cases multifocal HCC is associated with decreased survival and increased recurrence, potentially as an indication of already existing intrahepatic metastases. Although not prohibitive for resection, the presence of multiple lesions should alert the surgeon to the possibility of using treatments such as radiofrequency ablation and chemoembolization in combination with resection to obtain optimal results. Similar to multifocality, an increased tumor size is not necessarily prohibitive, but can serve as an indication of possible vascular invasion, which can in turn negatively affect the prognosis. When all of this is considered, the percentage of patients that can undergo hepatic resection under ideal conditions is less than 10%. However, even in this group of patients with cirrhosis, it is possible to achieve moderate long-term results [36-38].

### **3.1. Considerations in liver resection**

**2.2. Evaluation of hepatic reserve of patients with hepatocellular carcinoma**

ment, are also important pieces of information.

130 Cancer Treatment - Conventional and Innovative Approaches

**3. Hepatectomy**

As far as evaluating the hepatic reserve of the patient is concerned, that is a determination of both quantity and quality. This is a major change from the past when there were multiple exclusion criteria, as the only ones that have been consistently validated over time are the postoperative remnant liver volume and hepatic function [18-20]. It has been shown that if 3 or more hepatic segments are left behind after a resection, or an adequate hepatic remnant, which is 25% for a normal liver and 40% for a cirrhotic one, then postoperative liver dysfunction can be avoided [21-22]. This means that it is essential to be able to accurately estimate the liver remnant and the future remaining liver volume preoperatively, especially in the case of extended resections. The most reliable way to do this has been CT volumetry, which with the advent of the Digital Imaging and Communications in Medicine (DICOM) standard has enabled volumetry to be performed even by the surgeon on a personal computer. Quality can be assessed either directly (liver biopsy) or indirectly, through assessment of the synthetic function of the liver (INR, platelets, albumin) or other marks of portal hypertension and cirrhosis, such as esophagogastroduodenoscopy (EGD) looking for varices. The underlying chronic liver disease, including its duration and whether the patient has received any treat‐

By fully evaluating the patient with HCC, one can proceed more safely into determining whether the patient is a candidate for surgical treatment and which one: resection versus transplantation. Frequently, it may be necessary for the patient to be evaluated for both, as a patient undergoing a liver resection could show signs of hepatic failure postoperatively, leading to a discussion of whether transplantation is an option. It is wise for these decisions

The first question one has to consider when discussing the issue of hepatic resection for HCC is the presence or not of cirrhosis. In non-cirrhotic patients, hepatic resection represents the preferred treatment, as the lack of cirrhosis means that the patient can tolerate even an extended resection, and the non-cirrhotic liver will allow future re-resection, although it has a lower chance of de novo recurrence. Unfortunately, these patients without cirrhosis represent only 5% of cases in the West [23]. Even so, in these patients without cirrhosis, surgical resection for HCC can lead to 3-year survival of 46-76% and 5-year survivals of 30-50%, depending on the selection criteria and on whether fibrolamellar HCC cases are included in the study [24-26]. A high recurrence rate at 5 years of around 60% remains, even after potentially curative resections, possibly owing to intrahepatic metastases rather than existing disease, as the effect

In patients with cirrhosis, using proper selection criteria to avoid postoperative hepatic failure is critical. That set of criteria was originally based on the Child-Pugh classifica‐ tion, which however was not shown to have a consistent predictive value, as patients may show signs of hepatic dysfunction even at a stage of Child-Pugh A, thus making a resection

to be made beforehand, rather than during emotionally-charged times.

of the underlying chronic liver disease and the cirrhosis is not present [27].

When considering liver resection for HCC apart from the main question of the presence or absence of cirrhosis, there are other key issues to be addressed, such as ways to increase resectability, the differences between anatomic and non-anatomic resection and the use of laparoscopic surgery among others.

#### *3.1.1. The role of portal vein embolization*

In an effort to treat large HCC with hepatic resection or in those patients with inade‐ quate liver remnant, there are certain preoperative manoeuvres that can help increase resectability in these challenging patients. Preoperative portal vein embolization (PVE) was introduced in 1986 by Kinoshita to prevent postoperative hepatic insufficiency, whereas Makuuchi had first introduced the concept to clinical practice in 1982 for the treatment of hepatic cholangiocarcinoma [39-40]. The main principle is to occlude the portal venous flow to the side of the tumor, and cause ipsilateral atrophy and, more importantly, contralater‐ al hypertrophy of the part of the liver that will be the future remnant after the resection. This can lead to an increase in the future remnant by about 20-40% within 4-6 weeks, thus potentially increasing the pool of candidates for resection [41-43]. Although there are no absolute contraindications, especially as experience with the procedure continues to grow,

there are some relative ones, including uncorrectable coagulopathy, tumor invasion of the portal vein, biliary dilatation and renal failure. Bilobar disease used to be a contraindica‐ tion, however in light of the increased use of the two-stage hepatectomy, PVE can play a significant role in these patients [42,44]. Although there are two methods to access the portal vein for PVE, the transileocolic and the percutaneous transhepatic one, with both being equally effective, the percutaneous procedure has the distinct advantage of avoid‐ ing a minilaparotomy and general anesthesia. Regarding the choice of embolic agents, there is a great variety with similar results. However, since it is not an exact science how much embolic material or what size particles are needed to cause a specific amount of hypertro‐ phy and regeneration, we need to understand that this procedure is very much operatordependent. Certain principles need to be closely adhered to, such as embolizing till stasis is achieved, and also avoiding reflux of the embolic material into the veins that will supply the future liver remnant.

remains of what the proper margin for the nonanatomic resection is. Specifically, there is an ongoing debate as to whether a margin of 1cm or more is necessary to obtain disease-free survival, or whether less than 1cm is sufficient [49-51]. A prospective, randomized trial comparing narrow (1cm) to wide (2cm) resection margins identified a significant 5-year survival benefit (75% versus 49%) for the wide margin group, especially in patients with small HCC of 2cm or less [52]. Even so, a report by the Japan Society of Hepatology in 2010 states that "it is acceptable to resect a tumor with a minimum width so as to avoid exposing the tumor

The Role of Surgery in the Treatment of Hepatocellular Carcinoma

http://dx.doi.org/10.5772/55341

133

Although the first laparoscopic liver resection (LLR) was performed in 1992 by Gagner, it has been somewhat of an uphill struggle because of several reasons [54]. Potential difficulties of LLR include a significant learning curve, the perceived difficulty in control‐ ling hepatic bleeding should it occur, the lack of tactile sense which could affect the margins obtained and thus the oncological result of the procedure, the fear of port site metastases and that of gas embolism. To all of these we should add the lack of random‐ ized trials with LLR. Improvements in hepatic surgery, as well as in laparoscopic sur‐ gery, advances in the laparoscopic instruments used, and patient interest in minimally invasive procedures, have all led to a significant increase in the number and type of LLRs. There has also been increased use of LLRs for hepatic malignancies, as currently more than half of all LLRs are for primary or metastatic hepatic malignancies, including anatomic lobectomies and liver resections in cirrhotic patients [55-58]. The key factor is surgeon experience and the learning curve, as in one paper it was shown that the learning curve for minor laparoscopic hepatectomy could be overcome with 60 cases [59]. The surgeon needs to be a liver surgeon with knowledge of hepatic anatomy, as well as someone with experience in advanced laparoscopic surgery, so that issues such as control of vascular or biliary structures can be dealt with laparoscopically. Additionally, experience with laparoscopic ultrasound is mandatory, as it counterbalances the lack of tactile sense. Common sense dictates that at least the earliest laparoscopic procedures performed by a surgical team should include smaller, peripheral lesions away from major vascular structures or the hilum that can be approached with a laparoscopic wedge or segmental

In the case of HCC, several series have shown a good long-term outcome without jeopardizing patient safety [60-62]. Some of the findings in these studies included decreased blood loss and transfusion requirements for LLR, as well as a shorter length of stay. Although the latter may come as no surprise given the minimally invasive nature of the procedure, the former could be potentially attributed to new and improved coagulation and transection devices used in LLR. Another advantage of LLR is the possible decreased risk of hepatic function destabiliza‐ tion, if we consider that most of these patients have cirrhosis. It is believed that the lack of the big abdominal incisions, can cause less of an effect on the portal pressure, thus decreasing the risk of postoperative hepatic decompensation [63-64]. The result of the decreased biological and surgical stress for the patient could also be part of the reason why it was shown that prior

during hepatectomy for HCC" [53].

*3.1.3. Laparoscopic liver resection*

procedure.

There are some remaining concerns regarding PVE, such as whether PVE may stimulate the growth of hepatic tumor (of more interest in the case of hepatic metastases from colorectal or other cancers), or whether it is a safe procedure in patients with high-grade varices. The difficulty in answering these questions is the fact that we lack an understanding of the mechanism involved in the contralateral hypertrophy caused by the PVE. It is probably a combination of hepatic and extrahepatic factors, including cytokines (such as IL-6), growth factors (such as hepatocyte growth factor) and nutrient factors (insulin and glucagon), although the details are not yet clear [45]. Either way, PVE provides the surgical team with an important tool that if properly applied can lead to increased resectability of HCC.

#### *3.1.2. Anatomic versus non-anatomic hepatic resection*

Hepatic resection for malignant tumors can be anatomic or nonanatomic. The anatomic approach involves a resection of liver segments based on the segmental anatomy, whereas the nonanatomical approach involves a resection of the tumor with negative margins. The main argument in favour of the anatomic resection was made by Makuuchi and the Japanese school of thought, where based on the fact that HCC tends to metastasize via the portal venous system, it is believed that removing the tumor along the lines of hepatic segments, which would include the portal flow to the tumor, is the more oncologically sound approach [46-47]. Using a nationwide Japanese database of 72,744 patients to compare the outcome of anatomic versus nonanatomic resection for HCC, it was shown that there was no difference in overall survival, although with anatomic resection there was an improved disease-free survival [48]. The beneficial effect of anatomic resection was most prominent for HCC lesions 2 to 5 cm, some‐ thing which was explained by the fact that in smaller tumors there is very little chance of vascular invasion, whereas in bigger ones the high probability of vascular invasion and satellite lesions negates any advantage of an anatomic resection. Despite this, the extent of the hepa‐ tectomy should be primarily dictated by the extent of the existing chronic liver disease and the future liver remnant.

This type of argument has given impetus to the use of nonanatomic resection for HCC, as in the vast majority of cases the HCC occurs in the background of cirrhosis. Even so, the question remains of what the proper margin for the nonanatomic resection is. Specifically, there is an ongoing debate as to whether a margin of 1cm or more is necessary to obtain disease-free survival, or whether less than 1cm is sufficient [49-51]. A prospective, randomized trial comparing narrow (1cm) to wide (2cm) resection margins identified a significant 5-year survival benefit (75% versus 49%) for the wide margin group, especially in patients with small HCC of 2cm or less [52]. Even so, a report by the Japan Society of Hepatology in 2010 states that "it is acceptable to resect a tumor with a minimum width so as to avoid exposing the tumor during hepatectomy for HCC" [53].

#### *3.1.3. Laparoscopic liver resection*

there are some relative ones, including uncorrectable coagulopathy, tumor invasion of the portal vein, biliary dilatation and renal failure. Bilobar disease used to be a contraindica‐ tion, however in light of the increased use of the two-stage hepatectomy, PVE can play a significant role in these patients [42,44]. Although there are two methods to access the portal vein for PVE, the transileocolic and the percutaneous transhepatic one, with both being equally effective, the percutaneous procedure has the distinct advantage of avoid‐ ing a minilaparotomy and general anesthesia. Regarding the choice of embolic agents, there is a great variety with similar results. However, since it is not an exact science how much embolic material or what size particles are needed to cause a specific amount of hypertro‐ phy and regeneration, we need to understand that this procedure is very much operatordependent. Certain principles need to be closely adhered to, such as embolizing till stasis is achieved, and also avoiding reflux of the embolic material into the veins that will supply

There are some remaining concerns regarding PVE, such as whether PVE may stimulate the growth of hepatic tumor (of more interest in the case of hepatic metastases from colorectal or other cancers), or whether it is a safe procedure in patients with high-grade varices. The difficulty in answering these questions is the fact that we lack an understanding of the mechanism involved in the contralateral hypertrophy caused by the PVE. It is probably a combination of hepatic and extrahepatic factors, including cytokines (such as IL-6), growth factors (such as hepatocyte growth factor) and nutrient factors (insulin and glucagon), although the details are not yet clear [45]. Either way, PVE provides the surgical team with an

Hepatic resection for malignant tumors can be anatomic or nonanatomic. The anatomic approach involves a resection of liver segments based on the segmental anatomy, whereas the nonanatomical approach involves a resection of the tumor with negative margins. The main argument in favour of the anatomic resection was made by Makuuchi and the Japanese school of thought, where based on the fact that HCC tends to metastasize via the portal venous system, it is believed that removing the tumor along the lines of hepatic segments, which would include the portal flow to the tumor, is the more oncologically sound approach [46-47]. Using a nationwide Japanese database of 72,744 patients to compare the outcome of anatomic versus nonanatomic resection for HCC, it was shown that there was no difference in overall survival, although with anatomic resection there was an improved disease-free survival [48]. The beneficial effect of anatomic resection was most prominent for HCC lesions 2 to 5 cm, some‐ thing which was explained by the fact that in smaller tumors there is very little chance of vascular invasion, whereas in bigger ones the high probability of vascular invasion and satellite lesions negates any advantage of an anatomic resection. Despite this, the extent of the hepa‐ tectomy should be primarily dictated by the extent of the existing chronic liver disease and the

This type of argument has given impetus to the use of nonanatomic resection for HCC, as in the vast majority of cases the HCC occurs in the background of cirrhosis. Even so, the question

important tool that if properly applied can lead to increased resectability of HCC.

*3.1.2. Anatomic versus non-anatomic hepatic resection*

the future liver remnant.

132 Cancer Treatment - Conventional and Innovative Approaches

future liver remnant.

Although the first laparoscopic liver resection (LLR) was performed in 1992 by Gagner, it has been somewhat of an uphill struggle because of several reasons [54]. Potential difficulties of LLR include a significant learning curve, the perceived difficulty in control‐ ling hepatic bleeding should it occur, the lack of tactile sense which could affect the margins obtained and thus the oncological result of the procedure, the fear of port site metastases and that of gas embolism. To all of these we should add the lack of random‐ ized trials with LLR. Improvements in hepatic surgery, as well as in laparoscopic sur‐ gery, advances in the laparoscopic instruments used, and patient interest in minimally invasive procedures, have all led to a significant increase in the number and type of LLRs. There has also been increased use of LLRs for hepatic malignancies, as currently more than half of all LLRs are for primary or metastatic hepatic malignancies, including anatomic lobectomies and liver resections in cirrhotic patients [55-58]. The key factor is surgeon experience and the learning curve, as in one paper it was shown that the learning curve for minor laparoscopic hepatectomy could be overcome with 60 cases [59]. The surgeon needs to be a liver surgeon with knowledge of hepatic anatomy, as well as someone with experience in advanced laparoscopic surgery, so that issues such as control of vascular or biliary structures can be dealt with laparoscopically. Additionally, experience with laparoscopic ultrasound is mandatory, as it counterbalances the lack of tactile sense. Common sense dictates that at least the earliest laparoscopic procedures performed by a surgical team should include smaller, peripheral lesions away from major vascular structures or the hilum that can be approached with a laparoscopic wedge or segmental procedure.

In the case of HCC, several series have shown a good long-term outcome without jeopardizing patient safety [60-62]. Some of the findings in these studies included decreased blood loss and transfusion requirements for LLR, as well as a shorter length of stay. Although the latter may come as no surprise given the minimally invasive nature of the procedure, the former could be potentially attributed to new and improved coagulation and transection devices used in LLR. Another advantage of LLR is the possible decreased risk of hepatic function destabiliza‐ tion, if we consider that most of these patients have cirrhosis. It is believed that the lack of the big abdominal incisions, can cause less of an effect on the portal pressure, thus decreasing the risk of postoperative hepatic decompensation [63-64]. The result of the decreased biological and surgical stress for the patient could also be part of the reason why it was shown that prior LLR for HCC facilitated salvage liver transplantation with improved results compared to prior open liver resection [65].

to OLT and downstaging prior to OLT, and c) the role of living donor liver transplantation

The Role of Surgery in the Treatment of Hepatocellular Carcinoma

http://dx.doi.org/10.5772/55341

135

As mentioned above the most consistent prognostic factors regarding OLT for HCC are derived from the characteristics originating from the Milan criteria having to do with the size and number of the lesions, in addition to no macrovascular involvement and no extrahepatic metastatic disease to lymph nodes, lungs, bones, or other abdominal organs. These criteria can lead to 5-year survival of around 70% and recurrence-free survival of 70-80% [70-71]. In properly selected patients, it is possible to achieve even long-term results that are more than satisfactory with 9-year survival of 52% [72]. Getting to this point however has been challenging, as there is a continuous need to reevaluate the listing and

Originally, HCC was considered a contraindication for OLT given the dismal patient survival rates that were the result of patients being transplanted at a very late stage of their cancer, as the technique was still considered experimental. The combined work of Bismuth in 1993 and the subsequent Milan criteria by Mazzaferro showed that if patients were carefully chosen, so that the lesions were within a certain number and size, then it was possible to achieve these excellent results with OLT for HCC [70, 73]. Recently, however, several groups have argued that the Milan criteria are too restrictive and that more patients with HCC could benefit from OLT. The strongest argument along these lines is based on the University of California San Francisco (UCSF) criteria (single HCC lesion up to 6.5cm diameter or up to three lesions, none larger than 4.5cm, with a cumulative diameter of 8cm) [74]. Another retrospective study with the largest number of patients outside the Milan criteria has shown encouraging outcomes by using the "up-to-seven" rule [75]. This approach uses the sum of the combination of size and number covariates equal to seven or less. Although it appears as a strong proposal to expand the existing criteria, it does have the disadvantage of being based on post-transplant pathology. All of this has led many to discuss the "metroticket" theory, which is based on the belief that the further you go (the more you expand the existing criteria), the higher is the price you will be forced to pay (decreased survival and increased recurrence) [76]. In the United States, where the MELD score is used for listing, patients within the Milan criteria receive 22 MELD exception points for transplantation priority [77]. Despite an additional 10% increase in MELD every 3 months, patients may end up waiting 6 months to a year,

The fact that, despite receiving extra priority points on the waiting list, patients with HCC may still have to wait significantly and risk falling outside the Milan criteria, makes the issue of bridging therapy all the more important. Bridging therapy is mainly aimed towards patients that are already within Milan criteria and thus eligible for OLT, and for whom the goal is to avoid tumor progression while on the waiting list. Although it is hard to clarify the usefulness

(LDLT) for OLT.

**4.1. Results and criteria for OLT for HCC**

priority criteria for OLT for HCC.

depending on the region that they are [77].

**4.2. Bridging therapy to OLT for HCC**

### *3.1.4. HCC recurrence after resection*

HCC recurrence after hepatic resection is a significant concern with reported rates between 60-70% at 5 years [66-68]. The challenge lies in deciding what the best treatment for these patients is. The options include a second resection versus radiofrequency ablation versus salvage liver transplantation. Evaluating radiofrequency ablation has not been easy as there are significant variations in the inclusion criteria used in the various studies. Regarding OLT, an analysis of the UNOS database by Pelletier et al. reported a 61% 5-year intention to treat survival of patients with tumors within Milan criteria [69]. However, there have been studies advocating the use of a second resection in properly selected patients. In the largest study in the Western world a 5-year 67% overall survival was reported from a second resection after HCC recurrence, with the two main risk factors being gross vascular invasion and time to recurrence from primary resection less than a year [70]. It should be noted though that when these strict criteria were used, only 15% of patients with recurrence were candidates for a second resection.

#### *3.1.5. Liver resection as a bridge to OLT*

The issue of HCC recurrence raises an important question. When discussing the different surgical treatments of HCC, it is imperative to stress the fact that liver resection and OLT are not necessarily competitive surgical options, but can very frequently be seen as complimen‐ tary. Specifically, the cirrhotic patient who undergoes a hepatectomy for a HCC, no matter how stable the liver function is, certainly runs the risk of peri- or post-operative liver failure, thus necessitating an urgent evaluation and referral for OLT. The implication here is that patients with HCC and cirrhosis should be evaluated for both liver resection and OLT and preferably be treated at a center where both options are available.

### **4. Orthotopic liver transplantation for HCC**

Patients suffering from cirrhosis and HCC that are not candidates for resection, either because of the degree of liver disease or the location or anatomy of the tumor, are best treated by OLT. The main advantage is that OLT provides a solution for both the cirrhosis and the HCC. The problem arises from the fact that there is a limited organ supply, and for that reason there have been criteria established for patients to enter the waiting list. The most frequently used ones are the Milan criteria (single lesion less or equal to 5 cm in size or three or no more than three lesions, none of which are over 3cm in size), which can lead to 5-year survival of 70% [9]. There has been an effort to expand these criteria, as it has been shown that moderate expansion in terms of number and/or size of the lesions can lead to comparable survival.

This chapter will analyze the following issues having to do with OLT and HCC: a) results for OLT for HCC and criteria used to prioritize these patients, b) the practice of bridging therapies to OLT and downstaging prior to OLT, and c) the role of living donor liver transplantation (LDLT) for OLT.

### **4.1. Results and criteria for OLT for HCC**

LLR for HCC facilitated salvage liver transplantation with improved results compared to prior

HCC recurrence after hepatic resection is a significant concern with reported rates between 60-70% at 5 years [66-68]. The challenge lies in deciding what the best treatment for these patients is. The options include a second resection versus radiofrequency ablation versus salvage liver transplantation. Evaluating radiofrequency ablation has not been easy as there are significant variations in the inclusion criteria used in the various studies. Regarding OLT, an analysis of the UNOS database by Pelletier et al. reported a 61% 5-year intention to treat survival of patients with tumors within Milan criteria [69]. However, there have been studies advocating the use of a second resection in properly selected patients. In the largest study in the Western world a 5-year 67% overall survival was reported from a second resection after HCC recurrence, with the two main risk factors being gross vascular invasion and time to recurrence from primary resection less than a year [70]. It should be noted though that when these strict criteria were used, only 15% of patients with recurrence were candidates for a

The issue of HCC recurrence raises an important question. When discussing the different surgical treatments of HCC, it is imperative to stress the fact that liver resection and OLT are not necessarily competitive surgical options, but can very frequently be seen as complimen‐ tary. Specifically, the cirrhotic patient who undergoes a hepatectomy for a HCC, no matter how stable the liver function is, certainly runs the risk of peri- or post-operative liver failure, thus necessitating an urgent evaluation and referral for OLT. The implication here is that patients with HCC and cirrhosis should be evaluated for both liver resection and OLT and

Patients suffering from cirrhosis and HCC that are not candidates for resection, either because of the degree of liver disease or the location or anatomy of the tumor, are best treated by OLT. The main advantage is that OLT provides a solution for both the cirrhosis and the HCC. The problem arises from the fact that there is a limited organ supply, and for that reason there have been criteria established for patients to enter the waiting list. The most frequently used ones are the Milan criteria (single lesion less or equal to 5 cm in size or three or no more than three lesions, none of which are over 3cm in size), which can lead to 5-year survival of 70% [9]. There has been an effort to expand these criteria, as it has been shown that moderate expansion in

This chapter will analyze the following issues having to do with OLT and HCC: a) results for OLT for HCC and criteria used to prioritize these patients, b) the practice of bridging therapies

preferably be treated at a center where both options are available.

terms of number and/or size of the lesions can lead to comparable survival.

**4. Orthotopic liver transplantation for HCC**

open liver resection [65].

second resection.

*3.1.4. HCC recurrence after resection*

134 Cancer Treatment - Conventional and Innovative Approaches

*3.1.5. Liver resection as a bridge to OLT*

As mentioned above the most consistent prognostic factors regarding OLT for HCC are derived from the characteristics originating from the Milan criteria having to do with the size and number of the lesions, in addition to no macrovascular involvement and no extrahepatic metastatic disease to lymph nodes, lungs, bones, or other abdominal organs. These criteria can lead to 5-year survival of around 70% and recurrence-free survival of 70-80% [70-71]. In properly selected patients, it is possible to achieve even long-term results that are more than satisfactory with 9-year survival of 52% [72]. Getting to this point however has been challenging, as there is a continuous need to reevaluate the listing and priority criteria for OLT for HCC.

Originally, HCC was considered a contraindication for OLT given the dismal patient survival rates that were the result of patients being transplanted at a very late stage of their cancer, as the technique was still considered experimental. The combined work of Bismuth in 1993 and the subsequent Milan criteria by Mazzaferro showed that if patients were carefully chosen, so that the lesions were within a certain number and size, then it was possible to achieve these excellent results with OLT for HCC [70, 73]. Recently, however, several groups have argued that the Milan criteria are too restrictive and that more patients with HCC could benefit from OLT. The strongest argument along these lines is based on the University of California San Francisco (UCSF) criteria (single HCC lesion up to 6.5cm diameter or up to three lesions, none larger than 4.5cm, with a cumulative diameter of 8cm) [74]. Another retrospective study with the largest number of patients outside the Milan criteria has shown encouraging outcomes by using the "up-to-seven" rule [75]. This approach uses the sum of the combination of size and number covariates equal to seven or less. Although it appears as a strong proposal to expand the existing criteria, it does have the disadvantage of being based on post-transplant pathology. All of this has led many to discuss the "metroticket" theory, which is based on the belief that the further you go (the more you expand the existing criteria), the higher is the price you will be forced to pay (decreased survival and increased recurrence) [76]. In the United States, where the MELD score is used for listing, patients within the Milan criteria receive 22 MELD exception points for transplantation priority [77]. Despite an additional 10% increase in MELD every 3 months, patients may end up waiting 6 months to a year, depending on the region that they are [77].

#### **4.2. Bridging therapy to OLT for HCC**

The fact that, despite receiving extra priority points on the waiting list, patients with HCC may still have to wait significantly and risk falling outside the Milan criteria, makes the issue of bridging therapy all the more important. Bridging therapy is mainly aimed towards patients that are already within Milan criteria and thus eligible for OLT, and for whom the goal is to avoid tumor progression while on the waiting list. Although it is hard to clarify the usefulness of bridging therapy for patients with HCC, mainly because of the retrospective nature of most studies on the topic, it has been shown that the drop-out rate while on the waiting list increases as waiting time progresses, especially in the case of HCC [78]. Based on the estimates that have formed the basis of the UNOS MELD score exception policy, it is suggested to use bridging therapies for T2 patients, even if the estimated waiting time is less than 3 months [79].

for patients undergoing LDLT, since they have their own living donor, the question remains of what should happen if these recipients suffer hepatic dysfunction or nonfunction of the liver graft. That is, should they be listed in the deceased donor waiting list, something which would not have been possible before, given the size or number of their lesions. The answer at this point appears in most cases to be "no" and thus these are all considerations that should be carefully addressed by the surgical and medical teams before proceeding with a LDLT for HCC. Finally, as it has been seen in one of the bigger, multicenter trials in the US, the Adultto-Adult Living Donor Liver Transplantation Cohort Study (A2ALL), although the survival results between recipients of deceased donor and living donor transplantation are similar, there appears to be a higher chance of recurrence after the LDLT of 29% versus 0%, despite the much shorter waiting time (160 days for LDLT versus 469 days for deceased donor OLT) [88]. However, this could also be because of the shorter waiting time, as some would argue that by being able to proceed to transplantation quickly, one loses the "opportunity" to evaluate the

The Role of Surgery in the Treatment of Hepatocellular Carcinoma

http://dx.doi.org/10.5772/55341

137

Given the significant developments and progress in surgical technique, the biggest challenge in the treatment of HCC is identifying the biological behavior of a given tumor, so that a patient-tailored, or rather a tumor-targeted, treatment can be applied. To do this, it is necessary to identify those factors, other than tumor size and number, that determine tumor aggressive‐ ness. Several studies have identified a variety of parameters, such as the response to chemo‐ embolization, the presence of microvascular invasion, the degree of differentiation and the combination of total tumor volume (TTV) together with AFP as surrogate markers for the tumor's biological behavior [89-93]. Regarding the latter, in an overview of the Scientific Registry of Transplant Recipients data from March 2002 to January 2008, it was shown that AFP>400 ng/ml or TTV>115 cm3 led to a three-year survival of less than 50% [94]. Essentially, this represents a novel approach, where the issue is not necessary the number or size of the

The most promising area in terms of defining the nature and behavior of HCC is that of molecular biology, with the use of genetic markers. Currently, identification of targets such as vascular endothelial growth factor (VEGF) and platelet-derived growth factor receptor (PDGFR) has led to medications being used in clinical practice for advanced HCC, such as sorafenib and imatinib [95-98]. More importantly, the identification of microRNAs (miRNAs), which are a non-protein coding family of genes regulating gene expression, has opened a new window to the future. Specifically, they have been shown to function as oncogenes and tumor suppressor genes, making this a very useful screening tool for potential resection or liver transplantation candidates [99-100]. Several miRNA targets have been identified, with prominent among them miR-122a and miR-21, with the former being down-regulated and the latter up-regulated in HCC [101-102]. Advances in understanding the multistep process that is hepatic carcinogenesis, as well as beginning to identify the different signaling cascades involved, has provided researchers and clinicians with the opportunity to proceed with

biological behavior of the HCC.

HCC lesions per se, but rather the total tumor load.

**5. Future challenges**

Regarding the question of which therapy is best for bridging, the most promising therapy appears to be radiofrequency ablation, as several studies have shown decreased drop-out in radiofrequency ablation pretreated patients with a single HCC nodule [80-81]. Additionally, there may be a role for transarterial chemoembolization (TACE) for patients with lesions larger than 3cm or with a multinodular pattern, although this has not been verified in prospective studies. Another possibility, which is currently under investigation, is the use of transarterial radioembolization with Uttrium-90 microspheres, with promising results to this point [82-83].

### **4.3. Downstaging therapy for HCC prior to OLT**

Downstaging refers to the effort made in patients that find themselves outside the Milan or UCSF criteria for transplantability, to decrease their tumor burden to the extent that they fall within these criteria again. This way, these patients become candidates for OLT. Additionally, it is thought that the response to downstaging and the maintenance of this response represent a surrogate marker of the aggressiveness of the tumor, which in itself could help guide any decisions regarding the transplantability of a patient [84]. As to which the best method for downstaging is, TACE appears to have the advantage for single treatment, especially for multifocal tumors [84]. Even so, the combination of TACE, radiofrequency ablation and resection seems to be an even more effective method of downstaging compared to TACE alone (70% success versus 40%) [83, 85].

#### **4.4. The role of living donor liver transplantation in the management of HCC**

For many, LDLT represents a possible solution to the organ shortage problem and the long waiting list; for others it presents an opportunity for an aggressive approach in dealing with HCC patients whose tumors are outside the accepted criteria (such as the Milan and UCSF ones), if a suitable living donor exists. Currently in the US, LDLT represents about 5% of all liver transplantations. Despite the fact that the experience with LDLT is still being accumu‐ lated, there appears to be significant optimism. In one of the bigger studies from Japan with 316 patients undergoing LDLT for HCC, one- and three-year survivals were 78% and 69% respectively, whereas recurrence-free one- and three-year survivals were 73% and 65% [86]. Although these results may not seem as impressive at first, it should be noted that 54% of these patients were outside the Milan criteria, thus representing a higher risk group. Some studies have shown improved survival for patients undergoing LDLT compared to those undergoing OLT from deceased donors, with 1-year survival of 86% for LDLT versus 71% for deceased donor recipients [87]. Despite these encouraging results, there remains a lot of concern. The main reason is the consideration that the health of the living donor is placed at risk, as living donors are in the unique situation of undergoing a major surgical procedure without any health benefit to themselves. Additionally, regarding the argument of expanding HCC criteria for patients undergoing LDLT, since they have their own living donor, the question remains of what should happen if these recipients suffer hepatic dysfunction or nonfunction of the liver graft. That is, should they be listed in the deceased donor waiting list, something which would not have been possible before, given the size or number of their lesions. The answer at this point appears in most cases to be "no" and thus these are all considerations that should be carefully addressed by the surgical and medical teams before proceeding with a LDLT for HCC. Finally, as it has been seen in one of the bigger, multicenter trials in the US, the Adultto-Adult Living Donor Liver Transplantation Cohort Study (A2ALL), although the survival results between recipients of deceased donor and living donor transplantation are similar, there appears to be a higher chance of recurrence after the LDLT of 29% versus 0%, despite the much shorter waiting time (160 days for LDLT versus 469 days for deceased donor OLT) [88]. However, this could also be because of the shorter waiting time, as some would argue that by being able to proceed to transplantation quickly, one loses the "opportunity" to evaluate the biological behavior of the HCC.

### **5. Future challenges**

of bridging therapy for patients with HCC, mainly because of the retrospective nature of most studies on the topic, it has been shown that the drop-out rate while on the waiting list increases as waiting time progresses, especially in the case of HCC [78]. Based on the estimates that have formed the basis of the UNOS MELD score exception policy, it is suggested to use bridging therapies for T2 patients, even if the estimated waiting time is less than 3 months [79].

Regarding the question of which therapy is best for bridging, the most promising therapy appears to be radiofrequency ablation, as several studies have shown decreased drop-out in radiofrequency ablation pretreated patients with a single HCC nodule [80-81]. Additionally, there may be a role for transarterial chemoembolization (TACE) for patients with lesions larger than 3cm or with a multinodular pattern, although this has not been verified in prospective studies. Another possibility, which is currently under investigation, is the use of transarterial radioembolization with Uttrium-90 microspheres, with promising results to this point [82-83].

Downstaging refers to the effort made in patients that find themselves outside the Milan or UCSF criteria for transplantability, to decrease their tumor burden to the extent that they fall within these criteria again. This way, these patients become candidates for OLT. Additionally, it is thought that the response to downstaging and the maintenance of this response represent a surrogate marker of the aggressiveness of the tumor, which in itself could help guide any decisions regarding the transplantability of a patient [84]. As to which the best method for downstaging is, TACE appears to have the advantage for single treatment, especially for multifocal tumors [84]. Even so, the combination of TACE, radiofrequency ablation and resection seems to be an even more effective method of downstaging compared to TACE alone

**4.4. The role of living donor liver transplantation in the management of HCC**

For many, LDLT represents a possible solution to the organ shortage problem and the long waiting list; for others it presents an opportunity for an aggressive approach in dealing with HCC patients whose tumors are outside the accepted criteria (such as the Milan and UCSF ones), if a suitable living donor exists. Currently in the US, LDLT represents about 5% of all liver transplantations. Despite the fact that the experience with LDLT is still being accumu‐ lated, there appears to be significant optimism. In one of the bigger studies from Japan with 316 patients undergoing LDLT for HCC, one- and three-year survivals were 78% and 69% respectively, whereas recurrence-free one- and three-year survivals were 73% and 65% [86]. Although these results may not seem as impressive at first, it should be noted that 54% of these patients were outside the Milan criteria, thus representing a higher risk group. Some studies have shown improved survival for patients undergoing LDLT compared to those undergoing OLT from deceased donors, with 1-year survival of 86% for LDLT versus 71% for deceased donor recipients [87]. Despite these encouraging results, there remains a lot of concern. The main reason is the consideration that the health of the living donor is placed at risk, as living donors are in the unique situation of undergoing a major surgical procedure without any health benefit to themselves. Additionally, regarding the argument of expanding HCC criteria

**4.3. Downstaging therapy for HCC prior to OLT**

136 Cancer Treatment - Conventional and Innovative Approaches

(70% success versus 40%) [83, 85].

Given the significant developments and progress in surgical technique, the biggest challenge in the treatment of HCC is identifying the biological behavior of a given tumor, so that a patient-tailored, or rather a tumor-targeted, treatment can be applied. To do this, it is necessary to identify those factors, other than tumor size and number, that determine tumor aggressive‐ ness. Several studies have identified a variety of parameters, such as the response to chemo‐ embolization, the presence of microvascular invasion, the degree of differentiation and the combination of total tumor volume (TTV) together with AFP as surrogate markers for the tumor's biological behavior [89-93]. Regarding the latter, in an overview of the Scientific Registry of Transplant Recipients data from March 2002 to January 2008, it was shown that AFP>400 ng/ml or TTV>115 cm3 led to a three-year survival of less than 50% [94]. Essentially, this represents a novel approach, where the issue is not necessary the number or size of the HCC lesions per se, but rather the total tumor load.

The most promising area in terms of defining the nature and behavior of HCC is that of molecular biology, with the use of genetic markers. Currently, identification of targets such as vascular endothelial growth factor (VEGF) and platelet-derived growth factor receptor (PDGFR) has led to medications being used in clinical practice for advanced HCC, such as sorafenib and imatinib [95-98]. More importantly, the identification of microRNAs (miRNAs), which are a non-protein coding family of genes regulating gene expression, has opened a new window to the future. Specifically, they have been shown to function as oncogenes and tumor suppressor genes, making this a very useful screening tool for potential resection or liver transplantation candidates [99-100]. Several miRNA targets have been identified, with prominent among them miR-122a and miR-21, with the former being down-regulated and the latter up-regulated in HCC [101-102]. Advances in understanding the multistep process that is hepatic carcinogenesis, as well as beginning to identify the different signaling cascades involved, has provided researchers and clinicians with the opportunity to proceed with molecular classification of HCC [103-104]. This will provide critical information in terms of assessing the biological behavior of different HCCs, which in turn can help improve the therapeutic decision-making process.

[6] Marrero JA, Fontana RJ, Fu S, Conjeevaram HS, Su GL, Lok AS. Alcohol, tobacco and obesity are synergistic risk factors for hepatocellular carcinoma. J Hepatol 2005; 42:

The Role of Surgery in the Treatment of Hepatocellular Carcinoma

http://dx.doi.org/10.5772/55341

139

[7] Sangiovanni A, Del Ninno E, Fasani P, et al. Increased survival of cirrhotic patients with a hepatocellular carcinoma detected during surveillance. Gastroenterology

[8] Brechot C, Thiers V, Kremsdorf D, Nalpas B, Pol S, Paterlinin-Brechot P. Persistent hepatitis B virus infection in subjects without hepatitis B surface antigen: clinically

[9] Chen JD, Yang HI, Iloeje UH, et al. Carriers of inactive hepatitis B virus are still at risk for hepatocellular carcinoma and liver-related death. Gastroenterology 2010; 138:

[10] Minagawa M, Ikai I, Matsuyama Y, et al. Staging of hepatocellular carcinoma: assess‐ ment of the Japanese TNM and AJCC/UICC TNM systems in a cohort of 13,772 pa‐

[11] Okuda K, Ohtsuki T, Obata H, et al. Natural history of hepatocellular carcinoma and prognosis in relation to treatment. Study of 850 patients. Cancer 1985; 56: 918-928.

[12] Prospective validation of the CLIP score: a new prognostic system for patients with cirrhosis and hepatocellular carcinoma. The Cancer of the Liver Italian Program

[13] Kudo M, Chung H, Osaki Y. Prognostic staging system for hepatocellular carcinoma (CLIP score): its value and limitations, and a proposal for a new staging system, the

[14] Grieco A, Pompili M, Caminiti G, et al. Prognostic factors for survival in patients with early-intermediate hepatocellular carcinoma undergoing non-surgical therapy: comparison of Okuda, CLIP, and BCLC staging systems in a single Italian centre. Gut

[15] Sorensen JB, Klee M, Palshof T, Hansen HH. Performance status assessment in cancer patients. AN inter-observer variability study. Br J Cancer 1993; 67: 773-775.

[16] Verger E, Salamero M, Conill C. Can Karnofsky performance status be transformed to the Eastern Cooperative Oncology Group scoring scale and vice versa? Eur J Can‐

[17] Llovet JM, Fuster J, Bruix H. The Barcelona approach: diagnosis, staging and treat‐

[18] Shah SA, Haddad R, Al-Sukhni W, et al. Surgical resection of hepatic and pulmonary

ment of hepatocellular carcinoma. Liver Transpl 2004; 10: S115-S120.

metastases from colorectal carcinoma. J Am Coll Surg 2006; 202: 468-475.

Japan Integrated Staging Score (JIS score). J Gastroenterol 2003; 38: 207-215.

significant or purely "occult"? Hepatology 2001; 34: 194-203.

tients in Japan. Ann Surg 2007; 245: 909-922.

(CLIP) Investigators. Hepatology 2003; 31: 840-845.

218-224.

1747-1754.

2005; 54: 411-418.

cer 1992; 28: 1328-1330.

2004; 126: 1005-1014.

### **6. Conclusion**

Hepatocellular carcinoma is a disease with a far-reaching effect globally. The main therapeutic treatment method remains surgery, with the two options being liver resection or orthotopic liver transplantation. This chapter has discussed patient evaluation and selection for the different therapies, the advantages and disadvantages of liver resection and transplantation (with special emphasis on the fact that they both have a role in the continuum of care for these patients), and the future challenges and opportunities provided by the molecular tools available to today's surgeon.

### **Author details**

Georgios Tsoulfas1\* and Polyxeni Agorastou2

\*Address all correspondence to: tsoulfasg@gmail.com

1 Department of Surgery, Aristotle University of Thessaloniki, Greece

2 Department of Gastroenterology, Aristotle University of Thessaloniki, Greece

### **References**


[6] Marrero JA, Fontana RJ, Fu S, Conjeevaram HS, Su GL, Lok AS. Alcohol, tobacco and obesity are synergistic risk factors for hepatocellular carcinoma. J Hepatol 2005; 42: 218-224.

molecular classification of HCC [103-104]. This will provide critical information in terms of assessing the biological behavior of different HCCs, which in turn can help improve the

Hepatocellular carcinoma is a disease with a far-reaching effect globally. The main therapeutic treatment method remains surgery, with the two options being liver resection or orthotopic liver transplantation. This chapter has discussed patient evaluation and selection for the different therapies, the advantages and disadvantages of liver resection and transplantation (with special emphasis on the fact that they both have a role in the continuum of care for these patients), and the future challenges and opportunities provided by the molecular tools

therapeutic decision-making process.

138 Cancer Treatment - Conventional and Innovative Approaches

**6. Conclusion**

available to today's surgeon.

Georgios Tsoulfas1\* and Polyxeni Agorastou2

\*Address all correspondence to: tsoulfasg@gmail.com

1 Department of Surgery, Aristotle University of Thessaloniki, Greece

2 Department of Gastroenterology, Aristotle University of Thessaloniki, Greece

[2] El-Serag HB. Hepatocellular carcinoma. N Engl J Med 2011; 365: 118-127.

and hepatocellular carcinoma. Gastroenterology 2004; 126: 460-468.

[1] Parkin DM, Bray F, Ferlay J, Pisani P. Global cancer statistics 2002. CA Cancer J Clin

[3] Tanaka Y. Kurbanov F, Mano S, et al. Molecular tracing of the global hepatitis C vi‐ rus epidemic predicts regional patterns of hepatocellular carcinoma mortality. Gas‐

[4] El-Serag HB, Tran T, Everhart JE. Diabetes increases the risk of chronic liver disease

[5] Calle EE, Rodriguez C, Walker-Thurmond K, Thun MJ. Overweight, obesity, and mortality from cancer in a prospectively studied cohort of US adults. N Engl J Med

**Author details**

**References**

2005; 55: 74-108.

2003; 348: 1625-1638.

troenterology 2006; 130: 703-714.


[19] Fusai G, Davidson BR. Management of colorectal liver metastases. Colorectal Dis 2003; 5: 2-23.

[33] Ishizawa T, Hasegawa K, Aoki T, et al. Neither multiple tumors nor portal hyperten‐ sion are surgical contraindications for hepatocellular carcinoma. Gastroenterology

The Role of Surgery in the Treatment of Hepatocellular Carcinoma

http://dx.doi.org/10.5772/55341

141

[34] Cucchetti A, Ercolani G, Vivarelli M, et al. Impact of model for end-stage liver dis‐ ease (MELD) score on prognosis after hepatectomy for hepatocellular carcinoma on

[35] The SH, Christein J, Donohue J, et al. Hepatic resection of hepatocellular carcinoma in patients with cirrhosis: Model of End-Stage Liver Disease (MELD) score predicts

[36] Grazi GL, Ercolani G, Pierangeli F, et al. Improved results of liver resection for hepa‐ tocellular carcinoma on cirrhosis give the procedure added value. Ann Surg 2001;

[37] Fong Y, Sun RL, Jarnagin W, et al. An analysis of 412 cases of hepatocellular carcino‐

[38] Ercolani G, Grazi GL, Ravaioli M, et al. Liver resection for hepatocellular carcinoma on cirrhosis: univariate and multivariate analysis of risk factors for intrahepatic re‐

[39] Kinoshita H, Sakai K, Hirohashi K, et al. Preoperative portal vein embolization for

[40] Makuuchi M, Thai BL, Takayasu K, et al. Preoperative portal vein embolization to in‐ crease safety of major hepatectomy for hilar bile duct carcinoma: a preliminary re‐

[41] Farges O, Belghiti J, Kianmanesh R, et al. Portal vein embolization before right hepa‐

[42] Jaeck D, Bachellier P, Nakano H, et al. One or two-stage hepatectomy combined with portal vein embolization for initially nonresectable colorectal liver metastases. Am J

[43] Kaneko T, Nakao A, Takagi H. Clinical studies of new material for portal vein embo‐ lization: comparison of embolic effect with different agents. Hepatogastroenterology

[44] Madoff DC, Hicks ME, Vauthey JN, et al. Transhepatic portal vein embolization: anatomy, indications, and technical considerations. Radiographics 2002; 22:

[46] Hasegawa K, Kokudo N, Imamura H, et al. Prognostic impact of anatomic resection

[45] Michalopoulos GK, DeFrances MC. Liver regeneration. Science 1997; 276: 60-66.

for hepatocellular carcinoma. Ann Surg 2005; 242: 252-259.

perioperative mortality. J Gastrointest Surg 2005; 9: 1207-1215.

ma at a Western center. Ann Surg 1999; 229: 790-799.

hepatocellular carcinoma. World J Surg 1986; 10: 803-808.

tectomy: prospective clinical trial. Ann Surg 2003; 237: 208-217.

currence. Ann Surg 2003; 237: 536-543.

port. Surgery 1990; 107: 521-527.

Surg 2003; 185: 221-229.

2002; 49: 472-477.

1063-1076.

2008; 134: 1908-1916.

234: 71-78.

cirrhosis. Liver Transpl 2006; 12: 966-971.


[33] Ishizawa T, Hasegawa K, Aoki T, et al. Neither multiple tumors nor portal hyperten‐ sion are surgical contraindications for hepatocellular carcinoma. Gastroenterology 2008; 134: 1908-1916.

[19] Fusai G, Davidson BR. Management of colorectal liver metastases. Colorectal Dis

[20] Scheele J, Altendorf-Hofmann A, Grube T, et al. Resection of colorectal liver metasta‐ ses: what prognostic factors determine patient selection? Chirurg 2001; 72: 547-560.

[21] Schindl MJ, Redhead DN, Fearon KC, et al. The value of residual liver volume as a predictor of hepatic dysfunction and infection after major liver resection. Gut 2005;

[22] Shoup M, Gonen M, D'Angelica M, et al. Volumetric analysis predicts hepatic dys‐ function in patients undergoing major liver resection. J Gastrointest Surg 2003; 7:

[24] Chang CH, Chau GY, Lui WY, et al. Long-term results of hepatic resection for hepa‐ tocellular carcinoma originating from the noncirrhotic liver. Arch Surg 2004; 139:

[25] Laurent C, Blanc JF, Nobili S, et al. Prognostic factors and long-term survival after hepatic resection for hepatocellular carcinoma originating from noncirrhotic liver. J

[26] Verhoef C, de Man RA, Zondervan PE, et al. Good outcomes after resection of large hepatocellular carcinoma in the noncirrhotic liver. Dig Surg 2004; 21: 380-386.

[27] Lang H, Sotiropoulos GC, Brokalaki EI, et al. Survival and recurrence rates after re‐ section for hepatocellular carcinoma in noncirrhotic livers. J Am Coll Surg 2007; 205:

[28] Pugh RN, Murray-Lyon IM, Dawson JL, Pietroni MC, Williams R. Transection of the

[29] Llovet JM, Burroughs A, Bruix J. Hepatocellular carcinoma. Lancet 2003; 362:

[30] Bruix J, Castells A, Bosch J, et al. Surgical resection of hepatocellular carcinoma in cir‐ rhotic patients: prognostic value of preoperative portal pressure. Gastroenterology

[31] Llovet JM, Fuster J, Bruix J. Intention-to-treat analysis of surgical treatment for early hepatocellular carcinoma: resection versus transplantation. Hepatology 1999; 39:

[32] Bruix J, Sherman M. Management of hepatocellular carcinoma: an update. Hepatolo‐

esophagus for bleeding esophageal varices. Br J Surg 1973; 60: 646-649.

[23] Bismuth H, Mjno P. Hepatobiliary surgery. J Hepatol 2000; 32: 208-224

2003; 5: 2-23.

140 Cancer Treatment - Conventional and Innovative Approaches

54: 289-296.

325-330.

320-325.

27-36.

1907-1917.

1434-1440.

1996; 111: 1018-1022.

gy 2011; 53: 1020-1022.

Am Coll Surg 2005; 201: 656-662.


[47] Vauthey JN, Klimstra D, Franceschi D, et al. Factors affecting long-term outcome af‐ ter hepatic resection for hepatocellular carcinoma. Am J Surg 1995; 169: 28-34.

[61] Dagher I, Belli G, Fantini C, et al. Laparoscopic hepatectomy for hepatocellular carci‐

The Role of Surgery in the Treatment of Hepatocellular Carcinoma

http://dx.doi.org/10.5772/55341

143

[62] Zhou YM, Shao WY, Zhao YF, Xu DH, Li B. Meta-analysis of laparoscopic versus open resection for hepatocellular carcinoma. Dig Dis Sci 2011; 56: 1937-1943.

[63] Laurent A, Cherqui D, Lesurtel M, Brunetti F, Tayar C, Fagniez PL. Laparoscopic liv‐ er resection for subcapsular hepatocellular carcinoma complicating chronic liver dis‐

[64] Cai XJ, Yang J, Yu H, et al. Clinical study of laparoscopic versus open hepatectomy

[65] Laurent A, Tayar C, Andreoletti M, et al. Laparoscopic liver resection facilitates sal‐ vage liver transplantation for hepatocellular carcinoma. J Hepatobiliary Pancreat

[66] Roayaie S, Blume IN, Thung S, et al. A system of classifying microvascular invasion to predict outcome after resection in patients with hepatocellular carcinoma. Gastro‐

[67] Imamura H, Matsuyama Y, Tanaka E, et al. Risk factors contributing to early and late phase intrahepatic recurrence of hepatocellular carcinoma after hepatectomy. J Hepa‐

[68] Mazzaferro M, Romito R, Schiavo M, et al. Prevention of hepatocellular carcinoma recurrence with alpha-interferon after liver resection in HCV cirrhosis. Hepatology

[69] Pelletier SJ, Fu S, Thyagarajan V, et al. An intention-to-treat analysis of liver trans‐ plantation for hepatocellular carcinoma using organ procurement transplant net‐

[70] Mazzaferro V, Regalia E, Doci R, et al. Liver transplantation for the treatment of small hepatocellular carcinoma in patients with cirrhosis. N Engl J Med 1996; 334:

[71] Llovet JM, Bruix J, Fuster J, et al. Liver transplantation for small hepatocellular carci‐ noma: the tumor-node-metastasis classification does not have prognostic power.

[72] Majella Doyle MB, Vachharajani N, Maynard E, et al. Liver transplantation for hepa‐ tocellular carcinoma: long-term results suggest excellent outcomes. J Am Coll Surg

[73] Bismuth H, Cliché L, Adam R, Castaing D, Diamond T, Dennison A. Liver resection versus transplantation in cirrhotic patients with hepatocellular carcinoma in cirrho‐

noma: a European experience. J Am Coll Surg 2010; 211: 16-23.

for malignant liver tumors. Surg Endosc 2008; 22: 2350-2356.

ease. Arch Surg 2003; 138: 763-769.

Surg 2009; 16: 310-314.

tol 2003; 38: 200-207.

2006; 44: 1543-1554.

693-699.

2012; 215: 19-28.

enterology 2009; 137: 850-855.

work data. Liver Transpl 2009; 15: 859-868.

Hepatology 1998; 27:1572-1577.

sis. Ann Surg 1993; 218: 145-151.


[61] Dagher I, Belli G, Fantini C, et al. Laparoscopic hepatectomy for hepatocellular carci‐ noma: a European experience. J Am Coll Surg 2010; 211: 16-23.

[47] Vauthey JN, Klimstra D, Franceschi D, et al. Factors affecting long-term outcome af‐ ter hepatic resection for hepatocellular carcinoma. Am J Surg 1995; 169: 28-34.

[48] Eguchi S, Kanematsu T, Arii S, et al. Liver Cancer Study group of Japan. Comparison of the outcomes between an anatomical subsegmentectomy and a non-anatomical minor hepatectomy for single hepatocellular carcinomas based on a Japanese nation‐

[49] Lise M, Bacchetti S, Da Pian P, et al. Prognostic factors affecting long term outcome after liver resection for hepatocellular carcinoma: results in a series of 100 Italian pa‐

[50] Poon RT, Fan ST, Ng IO, et al. Significance of resection margin in hepatectomy for hepatocellular carcinoma: a critical reappraisal. Ann Surg 2000; 231: 544-551.

[51] Matsui Y, Terakawa N, Satoi S, et al. Postoperative outcomes in patients with hepato‐ cellular carcinomas resected with exposure of the tumor surface: clinical role of the

[52] Shi M, Guo RP, Lin XJ, et al. Partial hepatectomy with wide versus narrow resection margin for solitary hepatocellular carcinoma: a prospective randomized trial. Ann

[53] The Japan Society of Hepatology. Does width of the surgical margin contribute to

[54] Gagner M, Rheault M, Dubuc J. Laparoscopic partial hepatectomy for liver tumor.

[55] Nguyen KT, Gamblin TC, Geller DA. Laparoscopic liver resection for cancer. Futur

[56] Sasaki A, Nitta H, Otsuka K, et al. Ten-year experience of totally laparoscopic liver

[57] Gigot JF, Glineur D, Santiago Azagra J, et al. Laparoscopic liver resection for malig‐ nant liver tumors: preliminary results of a multicenter European study. Ann Surg

[58] Kazaryan AM, Mavango IP, Rosok BI, et al. Laparoscopic resection of colorectal liver metastases: surgical and long-term outcomes. Ann Surg 2010; 252: 1005-1012.

[59] Vigano L, Laurent A, Tayar C, et al. the learning curve in laparoscopic liver resection:

[60] Cherqui D, Laurent A, Tayar C, et al. Laparoscopic liver resection for peripheral hep‐ atocellular carcinoma in patients with chronic liver disease: midterm results and per‐

improved feasibility and reproducibility. Ann Surg 2009; 250: 772-782.

wide survey. Surgery 2008; 143: 469-475.

no-margin resection. Arch Surg 2007; 142: 596-602.

prognosis? Hepatology Research 2010; 40 (Suppl 1): 48-73.

resection in a single institution. Br J Surg 2009; 96: 274-279.

tients. Cancer 1998; 82: 1028-1036.

142 Cancer Treatment - Conventional and Innovative Approaches

Surg 2007; 245: 36-43.

Surg Endosc 1992; 6: 99.

Oncol 2008; 4: 661-670.

2002; 236: 90-97.

spectives. Ann Surg 2006; 243: 499-506.


[74] Yao FY, Roberts JP. Applying expanded criteria to liver transplantation for hepato‐ cellular carcinoma: too much, too soon, or is now the time? Liver Transpl 2004; 10: 919-921.

[87] Cheng SJ, Pratt DS, Freeman RB, et al. Living-donor versus cadaveric liver transplan‐ tation for non-resectable small hepatocellular carcinoma and compensated cirrhosis:

The Role of Surgery in the Treatment of Hepatocellular Carcinoma

http://dx.doi.org/10.5772/55341

145

[88] Fisher RA, Kulik LM, Freise CE, et al. Hepatocellular carcinoma recurrence and death following living and deceased donor liver transplantation. Am J Transplant

[89] Otto G, Herber S, Heise M, et al. Response to transarterial chemoembolization as a biological selection criteria for liver transplantation in hepatocellular carcinoma. Liv‐

[90] Cillo U, Vitale A, Bassanello M, et al. Liver transplantation for the treatment of mod‐ erately or well-differentiated hepatocellular carcinoma. Ann Surg 2004; 239: 150-159.

[91] Shirabe K, Itoh S, Yoshizumi T, et al. The predictors of microvascular invasion in can‐ didates for liver transplantation with hepatocellular carcinoma; with special refer‐ ence to the serum levels of des-gamma-carboxy Prothrombin. J Surg Oncol 2007; 95:

[92] Jonas S, Bechstein WO, Steinmmuler T, et al. Vascular invasion and histopathologic grading determine outcome after liver transplantation for hepatocellular carcinoma

[93] Sotiropoulos GC, Malago M, Bockhorn M, et al. Liver transplantation for hepatocel‐ lular carcinoma and cirrhosis in candidates with undetectable or very low alpha-feto‐ protein levels: is an expansion of listing criteria justified? Hepatogastroenterology

[94] Toso C, Asthana S, Bigam DL, Shapiro MJ, Kneteman NM. Reassessing selection cri‐ teria prior to liver transplantation for hepatocellular carcinoma utilizing the scientific

[95] Chiang DY, Villanueva A, Hoshida Y, et al. Focal gains of VEGFA and molecular classification of hepatocellular carcinoma. Cancer Res 2008; 68: 6779-6788.

[96] Liu L, Cao Y, Chen C, et al. Sorafenib blocks the RAF/MEK/ERK pathway, inhibits tumor angiogenesis, and induces tumor cell apoptosis in hepatocellular carcinoma

[97] Stock P, Monga D, Tan X, Micsenyi A, Loizos N, Monga SP. Platelet-derived growth factor receptor-alpha: a novel therapeutic target in human hepatocellular cancer. Mol

[98] Eckel F, von Delius S, Mayr M, et al. Pharmacokinetic and clinical phase II trial of imatinib in patients with impaired liver function and advanced hepatocellular carci‐

registry of transplant recipients database. Hepatology 2009; 49: 832-838.

a decision analysis. Transplantation 2001; 72: 861-868.

2007; 7: 1601-1608.

235-240.

2008; 55: 1671-1677.

er Transpl 2006; 12: 1260-1267.

in cirrhosis. Hepatology 2001; 33: 1080-1086.

model PLC/PRF/5. Cancer Res 2006; 66: 11851-11858.

Cancer Ther 2007; 6: 1932-1941.

noma. Oncology 2005; 69: 363-371.


[87] Cheng SJ, Pratt DS, Freeman RB, et al. Living-donor versus cadaveric liver transplan‐ tation for non-resectable small hepatocellular carcinoma and compensated cirrhosis: a decision analysis. Transplantation 2001; 72: 861-868.

[74] Yao FY, Roberts JP. Applying expanded criteria to liver transplantation for hepato‐ cellular carcinoma: too much, too soon, or is now the time? Liver Transpl 2004; 10:

[75] Mazzaferro V, Llovet JM, Miceli R, et al. Predicting survival after liver transplanta‐ tion in patients with hepatocellular carcinoma beyond the Milan criteria: a retrospec‐

[76] Bhoori S, Sposito C, Germini A, Coppa J, Mazzaferro V. The challenges of liver trans‐

[77] Pomfret EA, Washburn K, Wald, et al. Report of a national conference on liver alloca‐ tion in patients with hepatocellular carcinoma in the United States. Liver Transpl

[78] Freeman RB, Edwards EB, Harper AM. Waiting list removal rates among patients with chronic and malignant liver diseases. Am J Transplant 2006; 6: 1416-1421. [79] Llovet JM, Mas X, Aponte JJ, et al. Cost effectiveness of adjuvant therapy for hepato‐ cellular carcinoma during the waiting list for liver transplantation. Gut 2002; 50:

[80] Mazzaferro V, Battiston C, Perrone S, et al. Radiofrequency ablation of small hepato‐ cellular carcinoma in cirrhotic patients awaiting liver transplantation: a prospective

[81] Fontana RJ, Hamidullah H, Nghiem H, et al. Percutaneous radiofrequency thermal ablation of hepatocellular carcinoma: a safe and effective bridge to liver transplanta‐

[82] Geschwind JF, Salem R, Carr BI, et al. Yttrium-90 microspheres for the treatment of

[83] Lewandowski RJ, Kulik LM, Riaz A, et al. A comparative analysis of transarterial downstaging for hepatocellular carcinoma: chemoembolization versus Radioemboli‐

[84] Yao FY, Kerlan RK Jr, Hirose R, et al. Excellent outcome following down-staging of hepatocellular carcinoma prior to liver transplantation: an intention-to-treat analysis.

[85] Chapman WC, Majella Doyle MB, Stuart JE, et al. Outcomes of neoadjuvant transar‐ terial chemoembolization to downstage hepatocellular carcinoma before liver trans‐

[86] Todo S, Furukawa H. Living donor liver transplantation for adult patients with hepa‐

tocellular carcinoma: experience in Japan. Ann Surg 2004; 240: 451-459.

hepatocellular carcinoma. Gastroenterology 2004; 127: S194-S205.

plantation for hepatocellular carcinoma. Transpl Int 2010; 23: 712-722.

tive, exploratory analysis. Lancet Oncol 2009; 10: 35-43.

919-921.

144 Cancer Treatment - Conventional and Innovative Approaches

2010; 16: 262-278.

study. Ann Surg 2004; 240: 900-909.

tion. Liver Transpl 2002; 8: 1165-1174.

zation. Am J Transplant 2009; 9: 1920-1928.

plantation. Ann Surg 2008; 248: 617-625.

Hepatology 2008; 48: 819-827.

123-128.


[99] Esquela-Kerscher A, Slack FJ. Oncomirs-microRNAs with a role in cancer. Nat Rev Cancer 2006; 6: 259-269.

**Chapter 6**

**Laparoscopic Surgery in**

March Villalba José Antonio

http://dx.doi.org/10.5772/55448

**1. Introduction**

**Genitourinary Cancer Treatment**

Additional information is available at the end of the chapter

represents between 1% and 1.5% of male neoplasms [1].

Genitourinary cancer comprises kidney, prostate, bladder, upper urinary tract and testis neoplasms. The incidence rates of them vary between 15 and 1.5% in developed countries.

The epidemiology of genitourinary cancer varies depend on the organ. Prostate cancer is the most common solid neoplasm in males (15%) and renal cell neoplasm involves since 3% of all adult cancers. Urothelial carcinomas are the fourth most common tumors, after prostate, breast (females), lung and colorectal cancer. In particular, bladder cancer is the 9th most common cancer diagnosis worldwide. Testicular cancer is the less common genitourinary cancer that

The wide range of treatments against these diseases comprises surgery, radiotherapy and chemotherapy. Radiotherapy is used to treat localized and locally-advanced prostate cancer even with curative intent. Also radiotherapy is used to prophylactic treatment in seminoma‐ tous testis cancer to avoid para-aortic or iliac lymphatic relapses. In bladder cancer, radio‐ therapy is used as a palliative treatment against hematuria. Radiotherapy does not play an

Chemoteraphy in prostate cancer (Taxanes) is reserved for the treatment of metastatic castration refractory prostate cancer. At renal cell carcinoma, Tyrosine kinase inhibitors or Mammalian target of rapamycin (mTOR) inhibitors should be considered as first- or secondline treatment for metastatic disease. Cisplatin-based chemoteraphy in bladder cancer is considered as a neoadyuvant or adyuvant treatment before and after cystectomy if there is suspicion or evidence of lymph node metastasis. Carboplatin-based chemoteraphy is used to treat several seminomatous testis neoplasms stages after orchiectomy. Cisplatin, eposide and bleomycin or eposide and cisplatin combinations are used to treat non-seminomatous testis

> © 2013 Antonio; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

distribution, and reproduction in any medium, provided the original work is properly cited.

and reproduction in any medium, provided the original work is properly cited.

important role in kidney cancer, only it is used to treat selected metastasis cases.


### **Chapter 6**

### **Laparoscopic Surgery in Genitourinary Cancer Treatment**

March Villalba José Antonio

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/55448

### **1. Introduction**

[99] Esquela-Kerscher A, Slack FJ. Oncomirs-microRNAs with a role in cancer. Nat Rev

[100] He L, Hannon GJ. MicroRNAs: small RNAs with a big role in gene regulation. Nat

[101] Gramantieri L, Ferracin M, Fornari F, et al. Cyclin G1 is a target of miR-122a, a micro‐ RNA frequently down-regulated in human hepatocellular carcinoma. Cancer Res

[102] Meng F, Henson R, Wehbe-Janek H, Ghoshal K, Jacob ST, Patel T. MicroRNA-21 reg‐ ulates expression of the PTEN tumor suppressor gene in human hepatocellular can‐

[103] Farazi PA, De Pinho RA. Hepatocellular carcinoma pathogenesis: from genes to envi‐

[104] Villanueva A, Newell P, Chiang DY, Friedman SL, Llovet JM. Genomics and signal‐ ling pathways in hepatocellular carcinoma. Semin Liver Dis 2007; 27: 55-76.

Cancer 2006; 6: 259-269.

2007; 67: 6092-6099/

Rev Genet 2004; 5: 522-531.

146 Cancer Treatment - Conventional and Innovative Approaches

cer. Gastroenterology 2007; 133: 647-658.

ronment. Nat Rec Cancer 2006; 6: 674-687.

Genitourinary cancer comprises kidney, prostate, bladder, upper urinary tract and testis neoplasms. The incidence rates of them vary between 15 and 1.5% in developed countries.

The epidemiology of genitourinary cancer varies depend on the organ. Prostate cancer is the most common solid neoplasm in males (15%) and renal cell neoplasm involves since 3% of all adult cancers. Urothelial carcinomas are the fourth most common tumors, after prostate, breast (females), lung and colorectal cancer. In particular, bladder cancer is the 9th most common cancer diagnosis worldwide. Testicular cancer is the less common genitourinary cancer that represents between 1% and 1.5% of male neoplasms [1].

The wide range of treatments against these diseases comprises surgery, radiotherapy and chemotherapy. Radiotherapy is used to treat localized and locally-advanced prostate cancer even with curative intent. Also radiotherapy is used to prophylactic treatment in seminoma‐ tous testis cancer to avoid para-aortic or iliac lymphatic relapses. In bladder cancer, radio‐ therapy is used as a palliative treatment against hematuria. Radiotherapy does not play an important role in kidney cancer, only it is used to treat selected metastasis cases.

Chemoteraphy in prostate cancer (Taxanes) is reserved for the treatment of metastatic castration refractory prostate cancer. At renal cell carcinoma, Tyrosine kinase inhibitors or Mammalian target of rapamycin (mTOR) inhibitors should be considered as first- or secondline treatment for metastatic disease. Cisplatin-based chemoteraphy in bladder cancer is considered as a neoadyuvant or adyuvant treatment before and after cystectomy if there is suspicion or evidence of lymph node metastasis. Carboplatin-based chemoteraphy is used to treat several seminomatous testis neoplasms stages after orchiectomy. Cisplatin, eposide and bleomycin or eposide and cisplatin combinations are used to treat non-seminomatous testis

© 2013 Antonio; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

neoplasm combined or not to retroperitoneal lymph node nerve-sparring surgery and also in metastatic cases.

More and more genitourinary cancers are diagnosed in localized stages, making surgical treatment possible [1]. Since Bill Schuessler performed the first laparoscopic lymphadenecto‐ my in a patient with localized prostate cancer (October 1989), Urologists have acquired technology advances applied to laparoscopic surgery. In the last decades, those advances have made a minimally invasive approach to treat these cancers easier. That has caused that today laparoscopy approach is the technique of choice in the surgical treatment of some localized genitourinary cancers [2].

According the PUBMED database, there is an increase in the publication of articles dealing with the laparoscopic treatment. In the last 5 years almost 10% of those articles referring specifically to laparoscopic surgery. (Graphic 1).

Graphic 1. Evolution of published articles on laparoscopic surgery in PUBMED **Figure 1.** Evolution of published articles on laparoscopic surgery in PUBMED (MESH database).

(MESH database). Today there is a trend towards minimally invasive surgery but it is necessary to establish whether the outcomes of competing treatment options (open Vs laparoscopy) are comparable, focusing in postoperative morbidity and oncologic outcomes.

This chapter gives a summary of laparoscopic treatment reviewing the indication, morbidity and oncologic and functional results compared to conventional surgery for each of the listed cancers, providing a general overview.

23

**Table 1.** Kidney. Primary tumor stage (T) [41].

acceptable alternative to open surgery [3,4]

**Table 2.** Prostate. Pathologic tumor stage (pT) [42].

**2.1. Morbidity and functional outcomes**

(back pain and postoperative blood loss) and hospital stay [3].

Renal cell carcinoma (RCC) accounts for 2-3% of all adult cancers. More than 50% are diagnosed at a localized stage (pT1-pT2) (Table 2). Open radical or partial nephrectomy has been the standard curative intervention for localized RCC for the past five decades, laparoscopy also being an alternative in RCC with renal vein tumor thrombus (pT3a) (Table 2). With the new minimally invasive approaches, laparoscopic radical or partial nephrectomy has become an

Laparoscopic Surgery in Genitourinary Cancer Treatment

http://dx.doi.org/10.5772/55448

149

In comparison with open radical nephrectomy, laparoscopic procedure offers less morbidity

**2. Renal cancer**

**Table 1.** Kidney. Primary tumor stage (T) [41].

### **2. Renal cancer**

neoplasm combined or not to retroperitoneal lymph node nerve-sparring surgery and also in

More and more genitourinary cancers are diagnosed in localized stages, making surgical treatment possible [1]. Since Bill Schuessler performed the first laparoscopic lymphadenecto‐ my in a patient with localized prostate cancer (October 1989), Urologists have acquired technology advances applied to laparoscopic surgery. In the last decades, those advances have made a minimally invasive approach to treat these cancers easier. That has caused that today laparoscopy approach is the technique of choice in the surgical treatment of some localized

According the PUBMED database, there is an increase in the publication of articles dealing with the laparoscopic treatment. In the last 5 years almost 10% of those articles referring

Graphic 1. Evolution of published articles on laparoscopic surgery in PUBMED

Today there is a trend towards minimally invasive surgery but it is necessary to establish whether the outcomes of competing treatment options (open Vs laparoscopy) are comparable,

This chapter gives a summary of laparoscopic treatment reviewing the indication, morbidity and oncologic and functional results compared to conventional surgery for each of the listed

**Figure 1.** Evolution of published articles on laparoscopic surgery in PUBMED (MESH database).

focusing in postoperative morbidity and oncologic outcomes.

metastatic cases.

genitourinary cancers [2].

(MESH database).

cancers, providing a general overview.

specifically to laparoscopic surgery. (Graphic 1).

148 Cancer Treatment - Conventional and Innovative Approaches

Renal cell carcinoma (RCC) accounts for 2-3% of all adult cancers. More than 50% are diagnosed at a localized stage (pT1-pT2) (Table 2). Open radical or partial nephrectomy has been the standard curative intervention for localized RCC for the past five decades, laparoscopy also being an alternative in RCC with renal vein tumor thrombus (pT3a) (Table 2). With the new minimally invasive approaches, laparoscopic radical or partial nephrectomy has become an acceptable alternative to open surgery [3,4]


**Table 2.** Prostate. Pathologic tumor stage (pT) [42].

#### **2.1. Morbidity and functional outcomes**

23

In comparison with open radical nephrectomy, laparoscopic procedure offers less morbidity (back pain and postoperative blood loss) and hospital stay [3].

Nephron-sparing surgery offers better preservation of renal function than radical nephrecto‐ my and lower risk of cardiac death but efforts should be made to limit the renal function loss associated with surgery for localized renal masses regarding transient ischemia at surgery, because warm ischemia time seems to be the most important independent variable for predicting renal damage. This damage occurs within the third postoperative month [5,6].

*2.2.2. Locally-advanced renal cell carcinoma*

toneal and retroperitoneal approach.

on surgeon skill and renal mass anatomy.

improve methodological quality.

**3. Prostate cancer**

elements for a safe application of this approach.

**2.3. Conclusions**

survival.

Laparoscopic surgery has been extended to patients with renal cell carcinoma associated with limited local invasion and lymph node metastases or in the presence of renal vein and inferior vena cava thrombi. In well-selected patients with metastatic renal cell carcinoma, laparoscopic cytoreductive nephrectomy can be performed safely, with less morbidity than open nephrec‐ tomy [14]. Laparoscopic nephrectomy in metastatic RCC should be recommended to those patients with a good performance status before oncological treatment. The expanding indications for laparoscopic radical nephrectomy are: larger tumors (>7cm), renal vein tumor thrombus, cytoreductive nephrectomy and limited locally invasive tumors into psoas or

Laparoscopic Surgery in Genitourinary Cancer Treatment

http://dx.doi.org/10.5772/55448

151

For localized renal cancer, laparoscopic radical nephrectomy is the approach of choice because it offers less morbidity than open nephrectomy and both of them achieve similar oncological outcomes, such as survival and recurrence rates. There are no differences between transperi‐

When renal tumors are ≤ 4cm laparoscopic partial nephrectomy is a good choice but location of tumor is also important to perform surgery. In these cases, partial nephrectomy improves

Laparoscopic partial nephrectomy shows no improvement than laparoscopic radical neph‐ rectomy when renal tumors are > 4cm but laparoscopic approach is a correct choice depending

For locally-advanced renal cancer, laparoscopic radical nephrectomy is a technically feasible approach in carefully selected patients with a good performance status. Optimal patient selection, large laparoscopic experience and multidisciplinary support are the more important

Additional data are needed because most of the studies are retrospective and is necessary to

Prostate cancer (PCa) is one of the most common solid neoplasm in male. In Europe it has an incidence rate of 214 cases per 1000 men, outnumbering lung and colorectal cancer. PCa is

Currently, there is an increase in the diagnosis of PCa, concretely clinically localized prostate cancer (table 3). Radical prostatectomy is a common treatment for these patients, who have also life expectancy more than 10 years [17]. Radical prostatectomy has been associated with complications and sequel, including intraoperative blood loss, postoperative urinary inconti‐ nence and erectile dysfunction. With the intent of reducing the invasiveness of traditional open

currently the second most common cause of cancer death in men [16].

diaphragm muscle. This technique must be performed in selected patients [8,15]..

Laparoscopic nephron-sparing surgery provides less blood loss, median operative time, median analgesic requirement, hospital stay and median convalescence time, compared to open partial nephrectomy. But it means more major intra-operative complications (5% Vs 0%), renal / urological complications (11% Vs 2%) and warmer ischemia time [7].

### **2.2. Oncologic outcomes**

### *2.2.1. Localised renal cell carcinoma*

There are no randomised studies assessing oncological outcomes. Papers published found similar oncological outcomes; the 5 year overall survival for laparoscopic versus open radical nephrectomy was 87.8% and 88.7%, respectively. There was no evidence of any difference in cancer-specific and recurrence-free survival at 5 year reported in the studies [4].

With respect to the approach at localized RCC, few randomized studies compared retroperi‐ toneal with transperitoneal radical nephrectomy. Both of them were found to have a similar oncological outcomes and no incidences of positive surgical margins were reported [4,8].

When laparoscopic partial nephrectomy was compared to open partial nephrectomy, a database review of Lane *et al.* noted an overall survival benefit increase in laparoscopic versus open partial nephrectomy when adjusting for age, gender, race, Charlson index, tumor size, hypertension and the predicted risk of recurrence at 5 year in those patients with a minimum of 1 year follow-up, but there were no differences in 3 year cancer-specific survival, 5 year overall survival and 7 year follow-up (92.7% Vs 95.6% in cancer-specific survival respectively). This study described a lower risk of all-cause death in the laparoscopic group [9]. The same results were described by Gill *et al.* and Marszalek et al; both of them did not find differences in the recurrence patterns between both groups [10,11].

There has been controversy about the suitable tumor size to perform a laparoscopy nephronsparing intervention. A cut-off of 4cm has been recommended but some authors have argued that partial nephrectomy is feasible up to 7cm with no reduction in oncologic outcomes. In this view Simmons *et al.* published a database review for tumors larger than 4cm treated by laparoscopic partial nephrectomy versus laparoscopic radical nephrectomy. There was no difference in estimated overall survival (74% versus qué), cancer-specific survival and recurrence-free survival rates (both 81% versus qué) [4,12].

In addition to size, other factors about renal mass anatomy such as growth pattern (endo-/ meso-/exophytic) and location (central/hilar/peripheral, anterior/posterior, lateral/medial, polar) are important to consider a nephron-sparing surgery. It is more feasible if tumor is placed in a peripheral/polar/posterior site, for example [13].

### *2.2.2. Locally-advanced renal cell carcinoma*

Laparoscopic surgery has been extended to patients with renal cell carcinoma associated with limited local invasion and lymph node metastases or in the presence of renal vein and inferior vena cava thrombi. In well-selected patients with metastatic renal cell carcinoma, laparoscopic cytoreductive nephrectomy can be performed safely, with less morbidity than open nephrec‐ tomy [14]. Laparoscopic nephrectomy in metastatic RCC should be recommended to those patients with a good performance status before oncological treatment. The expanding indications for laparoscopic radical nephrectomy are: larger tumors (>7cm), renal vein tumor thrombus, cytoreductive nephrectomy and limited locally invasive tumors into psoas or diaphragm muscle. This technique must be performed in selected patients [8,15]..

### **2.3. Conclusions**

Nephron-sparing surgery offers better preservation of renal function than radical nephrecto‐ my and lower risk of cardiac death but efforts should be made to limit the renal function loss associated with surgery for localized renal masses regarding transient ischemia at surgery, because warm ischemia time seems to be the most important independent variable for predicting renal damage. This damage occurs within the third postoperative month [5,6].

Laparoscopic nephron-sparing surgery provides less blood loss, median operative time, median analgesic requirement, hospital stay and median convalescence time, compared to open partial nephrectomy. But it means more major intra-operative complications (5% Vs 0%),

There are no randomised studies assessing oncological outcomes. Papers published found similar oncological outcomes; the 5 year overall survival for laparoscopic versus open radical nephrectomy was 87.8% and 88.7%, respectively. There was no evidence of any difference in

With respect to the approach at localized RCC, few randomized studies compared retroperi‐ toneal with transperitoneal radical nephrectomy. Both of them were found to have a similar oncological outcomes and no incidences of positive surgical margins were reported [4,8].

When laparoscopic partial nephrectomy was compared to open partial nephrectomy, a database review of Lane *et al.* noted an overall survival benefit increase in laparoscopic versus open partial nephrectomy when adjusting for age, gender, race, Charlson index, tumor size, hypertension and the predicted risk of recurrence at 5 year in those patients with a minimum of 1 year follow-up, but there were no differences in 3 year cancer-specific survival, 5 year overall survival and 7 year follow-up (92.7% Vs 95.6% in cancer-specific survival respectively). This study described a lower risk of all-cause death in the laparoscopic group [9]. The same results were described by Gill *et al.* and Marszalek et al; both of them did not find differences

There has been controversy about the suitable tumor size to perform a laparoscopy nephronsparing intervention. A cut-off of 4cm has been recommended but some authors have argued that partial nephrectomy is feasible up to 7cm with no reduction in oncologic outcomes. In this view Simmons *et al.* published a database review for tumors larger than 4cm treated by laparoscopic partial nephrectomy versus laparoscopic radical nephrectomy. There was no difference in estimated overall survival (74% versus qué), cancer-specific survival and

In addition to size, other factors about renal mass anatomy such as growth pattern (endo-/ meso-/exophytic) and location (central/hilar/peripheral, anterior/posterior, lateral/medial, polar) are important to consider a nephron-sparing surgery. It is more feasible if tumor is

renal / urological complications (11% Vs 2%) and warmer ischemia time [7].

cancer-specific and recurrence-free survival at 5 year reported in the studies [4].

in the recurrence patterns between both groups [10,11].

recurrence-free survival rates (both 81% versus qué) [4,12].

placed in a peripheral/polar/posterior site, for example [13].

**2.2. Oncologic outcomes**

*2.2.1. Localised renal cell carcinoma*

150 Cancer Treatment - Conventional and Innovative Approaches

For localized renal cancer, laparoscopic radical nephrectomy is the approach of choice because it offers less morbidity than open nephrectomy and both of them achieve similar oncological outcomes, such as survival and recurrence rates. There are no differences between transperi‐ toneal and retroperitoneal approach.

When renal tumors are ≤ 4cm laparoscopic partial nephrectomy is a good choice but location of tumor is also important to perform surgery. In these cases, partial nephrectomy improves survival.

Laparoscopic partial nephrectomy shows no improvement than laparoscopic radical neph‐ rectomy when renal tumors are > 4cm but laparoscopic approach is a correct choice depending on surgeon skill and renal mass anatomy.

For locally-advanced renal cancer, laparoscopic radical nephrectomy is a technically feasible approach in carefully selected patients with a good performance status. Optimal patient selection, large laparoscopic experience and multidisciplinary support are the more important elements for a safe application of this approach.

Additional data are needed because most of the studies are retrospective and is necessary to improve methodological quality.

### **3. Prostate cancer**

Prostate cancer (PCa) is one of the most common solid neoplasm in male. In Europe it has an incidence rate of 214 cases per 1000 men, outnumbering lung and colorectal cancer. PCa is currently the second most common cause of cancer death in men [16].

Currently, there is an increase in the diagnosis of PCa, concretely clinically localized prostate cancer (table 3). Radical prostatectomy is a common treatment for these patients, who have also life expectancy more than 10 years [17]. Radical prostatectomy has been associated with complications and sequel, including intraoperative blood loss, postoperative urinary inconti‐ nence and erectile dysfunction. With the intent of reducing the invasiveness of traditional open retropubic approach and complications, urologists have developed the laparoscopic techni‐ que, which represents a different perspective of surgical anatomy that implies an important learning curve [17].

About urinary incontinence and erectile function, cumulative analysis of the available data suggestthatcontinenceratesanderectilefunctionafteropenorlaparoscopicapproacharesimilar [17,18]. The same occurs when quality of life after surgery was analyzed in both groups [17].

Laparoscopic Surgery in Genitourinary Cancer Treatment

http://dx.doi.org/10.5772/55448

153

With regard to the oncologic outcomes, in the published comparative studies, the main item evaluated was the surgical margins. Guazzoni et al published the study with the highest level of evidence, demonstrating that the positive surgical margins rates obtained after open retropubic radical prostatectomy and laparoscopic radical prostatectomy were overlapping [20]. In addition, when the data were stratified by the pathologic stages, there were no

Laparoscopy radical prostatectomy implies an important learning curve to achieve good functional and oncologic outcomes. Currently, laparoscopy approach is better than open approach in terms of perioperative and early postoperative outcomes such as: blood loss, transfusion requirements, tissue damage, postoperative pain (only the first few days), hospital

Several studies showed a lower rate of anastomotic stricture after laparoscopic approach.

There were no differences between retroperitoneal and transperitoneal approach [22].

the laparoscopic procedure, as well as the addition of lymphadenectomy.

**4. Urothelial cancer: Bladder and upper urinary tract**

At laparoscopic approach, the surgeon skill is very important to perform good bladder neck preservation, paraurethral dissection and nerve sparing surgery (when it is possible), to obtain good functional results. In general, laparoscopic approach does not offer more advantages in urinary continence or erectile function after surgery and the oncologic outcomes, compared

It is necessary more prospective studies, as well randomised series to analyze oncologic outcomes and morbidity comparing more than retroperitoneal or transperitoneal approach at

Itislikelythatthemostcriticalissueinsurgicaltreatmentoflocalizedprostatecanceristheselection of the best surgical technique fitted to the surgeon, rather than only the surgical approach.

Bladder cancer is the 9th most common cancer diagnosis worldwide, with an estimated male: female ratio of 3.8:1.0. At the initial diagnosis of bladder cancer approximately 30% has muscle-

**3.2. Oncologic outcomes**

**3.3. Conclusions**

stay, and full recovery time.

to open approach, are similar.

**4.1. Bladder cancer**

invasive disease [23].

differences between the two procedures [17,21].


**Table 3.** Urothelium. Primary tumor stage (T) [43,44].

### **3.1. Morbidity and functional outcomes**

Several studies demonstrate that operative time of laparoscopic approach was significantly longer than open retropubic approach, but laparoscopic approach showed less blood loss and lower transfusion rates than the open procedure [17,18]. The overall complications rate was significantly lower in those patients undergoing laparoscopy radical prostatectomy [17,18].

A single, nonrandomized prospective trial compared retropubic radical prostatectomy with laparoscopy prostatectomy, demonstrating that tissue damage was significantly lower in laparoscopic approach. Specifically, plasmatic levels of IL-6 and C-reactive protein were lower at the end of procedure, 12 hours later and 24 hours later [17].

In relation to postoperative pain (measured by validated 10-point visual analogue scale), laparoscopic radical prostatectomy with retroperitoneal approach seems to be the best tolerated technique during the first five postoperative days, compared with transperitoneal and open approaches [19]. Considering the studies reporting the requirements of morphine sulfate equivalent during the postoperative course, it seems to be no differences between open and laparoscopic approach [17].

In the published comparative studies, catheterization times and hospital stay were lower in laparoscopic approach [17]. Full recovery was faster in laparoscopic than open approach [18]. Laparoscopic radical prostatectomy had a lower rate of anastomotic strictures compared to open retropubic prostatectomy [17].

About urinary incontinence and erectile function, cumulative analysis of the available data suggestthatcontinenceratesanderectilefunctionafteropenorlaparoscopicapproacharesimilar [17,18]. The same occurs when quality of life after surgery was analyzed in both groups [17].

### **3.2. Oncologic outcomes**

retropubic approach and complications, urologists have developed the laparoscopic techni‐ que, which represents a different perspective of surgical anatomy that implies an important

Several studies demonstrate that operative time of laparoscopic approach was significantly longer than open retropubic approach, but laparoscopic approach showed less blood loss and lower transfusion rates than the open procedure [17,18]. The overall complications rate was significantly lower in those patients undergoing laparoscopy radical prostatectomy [17,18]. A single, nonrandomized prospective trial compared retropubic radical prostatectomy with laparoscopy prostatectomy, demonstrating that tissue damage was significantly lower in laparoscopic approach. Specifically, plasmatic levels of IL-6 and C-reactive protein were lower

In relation to postoperative pain (measured by validated 10-point visual analogue scale), laparoscopic radical prostatectomy with retroperitoneal approach seems to be the best tolerated technique during the first five postoperative days, compared with transperitoneal and open approaches [19]. Considering the studies reporting the requirements of morphine sulfate equivalent during the postoperative course, it seems to be no differences between open

In the published comparative studies, catheterization times and hospital stay were lower in laparoscopic approach [17]. Full recovery was faster in laparoscopic than open approach [18]. Laparoscopic radical prostatectomy had a lower rate of anastomotic strictures compared to

learning curve [17].

152 Cancer Treatment - Conventional and Innovative Approaches

**Table 3.** Urothelium. Primary tumor stage (T) [43,44].

**3.1. Morbidity and functional outcomes**

and laparoscopic approach [17].

open retropubic prostatectomy [17].

at the end of procedure, 12 hours later and 24 hours later [17].

With regard to the oncologic outcomes, in the published comparative studies, the main item evaluated was the surgical margins. Guazzoni et al published the study with the highest level of evidence, demonstrating that the positive surgical margins rates obtained after open retropubic radical prostatectomy and laparoscopic radical prostatectomy were overlapping [20]. In addition, when the data were stratified by the pathologic stages, there were no differences between the two procedures [17,21].

### **3.3. Conclusions**

Laparoscopy radical prostatectomy implies an important learning curve to achieve good functional and oncologic outcomes. Currently, laparoscopy approach is better than open approach in terms of perioperative and early postoperative outcomes such as: blood loss, transfusion requirements, tissue damage, postoperative pain (only the first few days), hospital stay, and full recovery time.

Several studies showed a lower rate of anastomotic stricture after laparoscopic approach.

At laparoscopic approach, the surgeon skill is very important to perform good bladder neck preservation, paraurethral dissection and nerve sparing surgery (when it is possible), to obtain good functional results. In general, laparoscopic approach does not offer more advantages in urinary continence or erectile function after surgery and the oncologic outcomes, compared to open approach, are similar.

There were no differences between retroperitoneal and transperitoneal approach [22].

It is necessary more prospective studies, as well randomised series to analyze oncologic outcomes and morbidity comparing more than retroperitoneal or transperitoneal approach at the laparoscopic procedure, as well as the addition of lymphadenectomy.

Itislikelythatthemostcriticalissueinsurgicaltreatmentoflocalizedprostatecanceristheselection of the best surgical technique fitted to the surgeon, rather than only the surgical approach.

### **4. Urothelial cancer: Bladder and upper urinary tract**

### **4.1. Bladder cancer**

Bladder cancer is the 9th most common cancer diagnosis worldwide, with an estimated male: female ratio of 3.8:1.0. At the initial diagnosis of bladder cancer approximately 30% has muscleinvasive disease [23].

Muscle invasive urothelial bladder cancer is a highly aggressive disease in which surgical treatment is essential for survival. Although open radical cystectomy is the gold standard treatment for muscle-invasive, organ-confined bladder carcinoma, there is increasing interest in laparoscopic radical cystectomy [24,25].

*4.1.2. Oncologic outcomes*

stage (0.3%) [29].

*4.1.3. Conclusions*

About surgical margins, both approaches obtained equivalent rates. The international Laparoscopic Cystectomy Registry has been established a surgical margins rate of 2%, compared to 1.6% for patients with organ-confined disease after open radical cystectomy [24, 27]. Chade *et al.* published an incidence of positive surgical margins ranged from 4-5% and

Laparoscopic Surgery in Genitourinary Cancer Treatment

http://dx.doi.org/10.5772/55448

155

Lymphadenectomy plays an important role in oncological outcome. Published reports showed an inferior average of nodal retrieval in laparoscopic procedure than in open approach. This

Local recurrence rates also appeared similar in both groups, around 7-10% [24]. Overall survival published in the laparoscopic series was 90-100% at 1-2 years and 63-79% at 2-3 years (selected cases), compared to open radical cystectomy series showing 62-68% at 5 years [25]. It is important to consider that the majority of published series had inadequate follow-up periods or/and the laparoscopic and open cohorts were no identical (strong selection bias) [28].

Port-site recurrence seems rare with current laparoscopic techniques for placement of the specimens into a laparoscopic bag, although there are few papers published on this topic. Tanaka *et al.,* for example, described one case of recurrence in a patient with a locally-advanced

Laparoscopic radical cystectomy is a difficult surgical technique specially to perform a correct pelvic lymphadenectomy. Today it cannot be considered an alternative to open approach because the postoperative series failed in selection criteria and follow-up period (not more

Hand-assisted laparoscopic radical cystectomy has a less period of learning curve but it decreases the advantages of a minimally invasive technique like pure laparoscopic cystectomy.

The extirpative component of laparoscopic cystectomy is well established. However laparo‐ scopic lymphadenectomy and reconstruction remains challenging, time-consuming, and could be associated with major complications. Shorter number of cases demonstrated that it

In conclusion, laparoscopic radical cystectomy with urinary diversion is a difficult procedure that should be reserved for selected cases (localized bladder cancer) and performed by

Urothelial carcinomas are the fourth most common tumors after prostate (males) or breast (females) cancer, lung cancer and colorectal cancer. They can be located in the upper urinary tract (pyelocaliceal cavities and ureter). Upper urinary tract carcinomas are uncommon and

is preferable to perform intracorporeal construction of the urinary diversion.

0-5% in open and laparoscopic approach respectively [25].

procedure strongly depends on the surgeon skills [25].

than 5 years). Multicentre prospective trials are needed.

experienced laparoscopic surgeons in selected centers.

**4.2. Upper urinary tract urothelial cell cancer**

Radical cystectomy is also an optional or recommended treatment in high grade tumors like T1G3 or Cis (table3) with high risk of progression and/or multiple recurrences after immuno‐ therapy (intravesical BCG) treatment [23].

Laparoscopic radical cystectomy could be divided in three times: 1, cystoprostatectomy in males or cystectomy plus hysterectomy and ooforectomy in females; 2, lymphadenectomy and 3, urinary device reconstruction (intra or extracorporeal).

At this surgery it is necessary to have performed a correct selection criteria, including organconfined disease (≤T3), nonbulky limphadenopathy, absence of uncorrected coagulopathy, body mass index < 35 kg/m2 , non severe cardiorespiratory compromise and absence of prior abdominal surgery or prior pelvic radiation therapy, because it has been shown that the patients who do not meet these criteria have higher complication rates and poor profit of lymphadenectomy [24].

About lymphadenectomy, there is strong evidence that the more nodes removed at cystecto‐ my, the better long-term survival time, so it is very important the extent of the lympadenec‐ tomy and the number of nodes removed. At laparosopic approach, it requires high-level laparoscopic skills [24].

### *4.1.1. Morbidity and functional outcomes*

General postoperative complications rate of open radical cystectomy vary between 30%-60% of patientsandthemortalityisabout1.5%.Atlaparoscopiccystectomythereportedratesfallbetween 8%-42% and 1% of mortality, but these reports do not define blood transfusion as a complication [24]. Nix *et al.* performed the only randomized controlled trial and reported no difference in complicationsbetweenopenandlaparoscopicapproach,butthegroupsweretoosmall[26].Haber *et al.* in their retrospectively series (n=50 in each group) showed an important benefit for the laparoscopic approach and extracorporeal urinary diversion. These cases were associated with reducedbloodloss,decreasedileus,shorterhospitalstayandnodifferencesinoperatingtimeand post-operativecomplications,andappeartohavelesspostoperativeanalgesicrequirements[27].

The indications or nerve-sparing cystectomy are limited to selected young patients with organconfined low-volume of tumor and extratrigonal location who are keen to maintain their sexual potency. This preservation has rarely been analyzed and the series published lacked potency data. Prostate-sparing radical cystectomy, another way to preserve erection, is controversial, and there are no data about long-term oncological outcomes to validate their safety [27].

Regarding to urinary diversion, Haber *et al.* showed that the laparoscopic assisted urinary diversion technique provides decreases in operating time, blood loss, transfusion rate, and more rapidpostoperativereturntooralintakeandambulation,althoughmajorcomplicationsrequiring re-operation occurred more in this group than in the extracorporeal reconstruction [27].

### *4.1.2. Oncologic outcomes*

Muscle invasive urothelial bladder cancer is a highly aggressive disease in which surgical treatment is essential for survival. Although open radical cystectomy is the gold standard treatment for muscle-invasive, organ-confined bladder carcinoma, there is increasing interest

Radical cystectomy is also an optional or recommended treatment in high grade tumors like T1G3 or Cis (table3) with high risk of progression and/or multiple recurrences after immuno‐

Laparoscopic radical cystectomy could be divided in three times: 1, cystoprostatectomy in males or cystectomy plus hysterectomy and ooforectomy in females; 2, lymphadenectomy and

At this surgery it is necessary to have performed a correct selection criteria, including organconfined disease (≤T3), nonbulky limphadenopathy, absence of uncorrected coagulopathy,

abdominal surgery or prior pelvic radiation therapy, because it has been shown that the patients who do not meet these criteria have higher complication rates and poor profit of

About lymphadenectomy, there is strong evidence that the more nodes removed at cystecto‐ my, the better long-term survival time, so it is very important the extent of the lympadenec‐ tomy and the number of nodes removed. At laparosopic approach, it requires high-level

General postoperative complications rate of open radical cystectomy vary between 30%-60% of patientsandthemortalityisabout1.5%.Atlaparoscopiccystectomythereportedratesfallbetween 8%-42% and 1% of mortality, but these reports do not define blood transfusion as a complication [24]. Nix *et al.* performed the only randomized controlled trial and reported no difference in complicationsbetweenopenandlaparoscopicapproach,butthegroupsweretoosmall[26].Haber *et al.* in their retrospectively series (n=50 in each group) showed an important benefit for the laparoscopic approach and extracorporeal urinary diversion. These cases were associated with reducedbloodloss,decreasedileus,shorterhospitalstayandnodifferencesinoperatingtimeand post-operativecomplications,andappeartohavelesspostoperativeanalgesicrequirements[27].

The indications or nerve-sparing cystectomy are limited to selected young patients with organconfined low-volume of tumor and extratrigonal location who are keen to maintain their sexual potency. This preservation has rarely been analyzed and the series published lacked potency data. Prostate-sparing radical cystectomy, another way to preserve erection, is controversial, and there are no data about long-term oncological outcomes to validate their safety [27].

Regarding to urinary diversion, Haber *et al.* showed that the laparoscopic assisted urinary diversion technique provides decreases in operating time, blood loss, transfusion rate, and more rapidpostoperativereturntooralintakeandambulation,althoughmajorcomplicationsrequiring

re-operation occurred more in this group than in the extracorporeal reconstruction [27].

, non severe cardiorespiratory compromise and absence of prior

in laparoscopic radical cystectomy [24,25].

154 Cancer Treatment - Conventional and Innovative Approaches

therapy (intravesical BCG) treatment [23].

body mass index < 35 kg/m2

lymphadenectomy [24].

laparoscopic skills [24].

*4.1.1. Morbidity and functional outcomes*

3, urinary device reconstruction (intra or extracorporeal).

About surgical margins, both approaches obtained equivalent rates. The international Laparoscopic Cystectomy Registry has been established a surgical margins rate of 2%, compared to 1.6% for patients with organ-confined disease after open radical cystectomy [24, 27]. Chade *et al.* published an incidence of positive surgical margins ranged from 4-5% and 0-5% in open and laparoscopic approach respectively [25].

Lymphadenectomy plays an important role in oncological outcome. Published reports showed an inferior average of nodal retrieval in laparoscopic procedure than in open approach. This procedure strongly depends on the surgeon skills [25].

Local recurrence rates also appeared similar in both groups, around 7-10% [24]. Overall survival published in the laparoscopic series was 90-100% at 1-2 years and 63-79% at 2-3 years (selected cases), compared to open radical cystectomy series showing 62-68% at 5 years [25]. It is important to consider that the majority of published series had inadequate follow-up periods or/and the laparoscopic and open cohorts were no identical (strong selection bias) [28].

Port-site recurrence seems rare with current laparoscopic techniques for placement of the specimens into a laparoscopic bag, although there are few papers published on this topic. Tanaka *et al.,* for example, described one case of recurrence in a patient with a locally-advanced stage (0.3%) [29].

#### *4.1.3. Conclusions*

Laparoscopic radical cystectomy is a difficult surgical technique specially to perform a correct pelvic lymphadenectomy. Today it cannot be considered an alternative to open approach because the postoperative series failed in selection criteria and follow-up period (not more than 5 years). Multicentre prospective trials are needed.

Hand-assisted laparoscopic radical cystectomy has a less period of learning curve but it decreases the advantages of a minimally invasive technique like pure laparoscopic cystectomy.

The extirpative component of laparoscopic cystectomy is well established. However laparo‐ scopic lymphadenectomy and reconstruction remains challenging, time-consuming, and could be associated with major complications. Shorter number of cases demonstrated that it is preferable to perform intracorporeal construction of the urinary diversion.

In conclusion, laparoscopic radical cystectomy with urinary diversion is a difficult procedure that should be reserved for selected cases (localized bladder cancer) and performed by experienced laparoscopic surgeons in selected centers.

### **4.2. Upper urinary tract urothelial cell cancer**

Urothelial carcinomas are the fourth most common tumors after prostate (males) or breast (females) cancer, lung cancer and colorectal cancer. They can be located in the upper urinary tract (pyelocaliceal cavities and ureter). Upper urinary tract carcinomas are uncommon and account for only 5-10% of urothelial carcinomas. In 8-13% of patients, concurrent bladder cancer is present [30].

**5.1. Morbidity and functional outcomes**

2-3% [34-36].

**5.2. Oncologic outcome**

**5.3. Conclusion**

was associated with longer operating time [34-36].

outcomes comparable with open surgery [35].

as on the role of post chemotherapy [33,34].

logic surgery. To minimize minimal invasive surgery.

Compared with open retroperitoneal lymph node dissection, laparoscopic approach, done by expert hands, showed improvements in terms of analgesic requirements, complication rate (15.6% Vs 33%), re-do surgery rate (1.4% Vs 6.6%) and hospital stay but laparoscopic approach

Laparoscopic Surgery in Genitourinary Cancer Treatment

http://dx.doi.org/10.5772/55448

157

Complication rates about laparoscopic approach varied between 5.6% and 46.7%. Major intraoperative complications included bleeding and ureteral, duodenal and gallbladder injury. In expert hands the vast of complications could be managed laparoscopically as low conversion rates reported (1-5.4%). About retrograde ejaculation, a late complication, reports showed a

Retroperitoneal laparoscopic lymph node dissection was described by some authors. Results showed its equivalence compared to conventional transperitoneal laparoscopic approach [37].

Regarding stage I nonseminomatous germ cell tumor (any stage but not lymph node invasion or metastasis), there were no differences between open and laparoscopic approach in terms of retroperitoneal relapse, distant progression, biochemical failure and in-field relapse. There were three reports of port-site metastasis (0.3%) in the literature. The rate of positive lymph nodes was lower after laparoscopic approach. The need for secondary retroperitoneal surgery did not differ (1.1-1.5%) and both groups showed similar cure rates (99.6%-100%) [34].

To justify laparoscopic approach instead of open surgery, laparoscopic retroperitoneal lymph node dissection is a safe procedure with low complication rate and with perioperative

The consensus of the authors is that open or laparoscopic retroperitoneal lymph node dissec‐ tion should be concentrated in dedicated referral centers. Thus laparoscopic lymph node resection might be indicated in: low-risk stages, if primary tumor contains mature teratoma or if the primary nonseminomatous germ cell tumor is marker negative. Laparoscopic retroperitoneal lymph node dissection represents a valuable tool for selected patients with clinical stage I. Further studies should focus on the curative potential of the procedures as well

Laparoendoscopic single-site and natural orifice transluminal endoscopic in Urology onco‐

Natural orifice transluminal endoscopic surgery (NOTES) and laparoendoscopic single-site surgery (LESS) have been developed to reduce morbidity and scarring. NOTES uses existing orifices of the human body to perform surgical or diagnostic techniques. The use of accessory transabdominal ports as a part of evolution of NOTES is defined as *hybrid* NOTES. LESS

procedure implies only a single-port or a single-incision laparoscopy [38].

Laparoscopic radical nephroureterectomy is reserved for localized disease (the tumor not invades beyond peripelvic or periureteric fat or renal parenchyma). This technique must comply with oncologic principles, which consists on preventing tumour seeding by avoiding drilling the upper urinary tract during resection. The excision includes the distal ureter to avoid recurrence. In the first experience there were reports of retroperitoneal metastatic or trocar dissemination when locally-advanced tumors are manipulated [30]. Laparoscopic nephrour‐ eterectomy must take a place in a closed system, tumor morcelation should be avoided and an endobag is necessary to extract the specimen (kidney and ureter removed en bloc with the bladder cuff) [30].

Open and laparoscopic access seems to be equivalent in terms of efficacy and oncologic results, but regarding to functional outcomes laparoscopy approach is superior to open surgery (as in the laparoscopy nephrectomy). Laparoscopic approach resulted in less blood loss, shorter hospital stay, decreased analgesic use, a shorter interval to oral intake, a decreased analgesic use and a decrease interval to convalescence, with no significant difference in the rate of perioperative complications [30,31].

Laparoscopy lymph node dissection associated with nephroureterectomy allows for optimal staging and has a therapeutic purpose. However, the anatomic areas to perform it have not yet clearly defined and it is not possible to standardize the indications to perform an extended lymphadenectomy because the published data are retrospective [30].

Several reports analyzed retroperitoneoscopic nephroureterectomy; most of them found that this approach was associated with longer operative times. However, blood loss, analgesic use, and length of hospital stay were decreased in comparison to open approach [31].

In conclusion, laparoscopic nephroureterectomy is a feasible approach at localized upper urinary tract tumors when it is impossible to perform a conservative treatment.

### **5. Testicular cancer**

Testicular cancer represents between 1% and 1.5% of male neoplasms and 5% of urological tumors in general. About 15-20% of stage I (no clinical node metastasis) seminoma and up to 30% of nonseminomatous germ cells cancer patients have subclinical metastases. Surgical resection is the gold standard for managing postchemotherapy residual retroperitoneal tumor mass cases [32,33].

Laparoscopic surgery in testicular cancer is focused on the treatment of residual retroperito‐ neal mass or lymph node metastasis after chemotherapy. Retroperitoneal lymph node dissection is still a diagnostic and therapeutic option mainly in stage I disease [34,33].

### **5.1. Morbidity and functional outcomes**

account for only 5-10% of urothelial carcinomas. In 8-13% of patients, concurrent bladder

Laparoscopic radical nephroureterectomy is reserved for localized disease (the tumor not invades beyond peripelvic or periureteric fat or renal parenchyma). This technique must comply with oncologic principles, which consists on preventing tumour seeding by avoiding drilling the upper urinary tract during resection. The excision includes the distal ureter to avoid recurrence. In the first experience there were reports of retroperitoneal metastatic or trocar dissemination when locally-advanced tumors are manipulated [30]. Laparoscopic nephrour‐ eterectomy must take a place in a closed system, tumor morcelation should be avoided and an endobag is necessary to extract the specimen (kidney and ureter removed en bloc with the

Open and laparoscopic access seems to be equivalent in terms of efficacy and oncologic results, but regarding to functional outcomes laparoscopy approach is superior to open surgery (as in the laparoscopy nephrectomy). Laparoscopic approach resulted in less blood loss, shorter hospital stay, decreased analgesic use, a shorter interval to oral intake, a decreased analgesic use and a decrease interval to convalescence, with no significant difference in the rate of

Laparoscopy lymph node dissection associated with nephroureterectomy allows for optimal staging and has a therapeutic purpose. However, the anatomic areas to perform it have not yet clearly defined and it is not possible to standardize the indications to perform an extended

Several reports analyzed retroperitoneoscopic nephroureterectomy; most of them found that this approach was associated with longer operative times. However, blood loss, analgesic use,

In conclusion, laparoscopic nephroureterectomy is a feasible approach at localized upper

Testicular cancer represents between 1% and 1.5% of male neoplasms and 5% of urological tumors in general. About 15-20% of stage I (no clinical node metastasis) seminoma and up to 30% of nonseminomatous germ cells cancer patients have subclinical metastases. Surgical resection is the gold standard for managing postchemotherapy residual retroperitoneal tumor

Laparoscopic surgery in testicular cancer is focused on the treatment of residual retroperito‐ neal mass or lymph node metastasis after chemotherapy. Retroperitoneal lymph node

dissection is still a diagnostic and therapeutic option mainly in stage I disease [34,33].

and length of hospital stay were decreased in comparison to open approach [31].

urinary tract tumors when it is impossible to perform a conservative treatment.

lymphadenectomy because the published data are retrospective [30].

cancer is present [30].

156 Cancer Treatment - Conventional and Innovative Approaches

bladder cuff) [30].

perioperative complications [30,31].

**5. Testicular cancer**

mass cases [32,33].

Compared with open retroperitoneal lymph node dissection, laparoscopic approach, done by expert hands, showed improvements in terms of analgesic requirements, complication rate (15.6% Vs 33%), re-do surgery rate (1.4% Vs 6.6%) and hospital stay but laparoscopic approach was associated with longer operating time [34-36].

Complication rates about laparoscopic approach varied between 5.6% and 46.7%. Major intraoperative complications included bleeding and ureteral, duodenal and gallbladder injury. In expert hands the vast of complications could be managed laparoscopically as low conversion rates reported (1-5.4%). About retrograde ejaculation, a late complication, reports showed a 2-3% [34-36].

Retroperitoneal laparoscopic lymph node dissection was described by some authors. Results showed its equivalence compared to conventional transperitoneal laparoscopic approach [37].

### **5.2. Oncologic outcome**

Regarding stage I nonseminomatous germ cell tumor (any stage but not lymph node invasion or metastasis), there were no differences between open and laparoscopic approach in terms of retroperitoneal relapse, distant progression, biochemical failure and in-field relapse. There were three reports of port-site metastasis (0.3%) in the literature. The rate of positive lymph nodes was lower after laparoscopic approach. The need for secondary retroperitoneal surgery did not differ (1.1-1.5%) and both groups showed similar cure rates (99.6%-100%) [34].

#### **5.3. Conclusion**

To justify laparoscopic approach instead of open surgery, laparoscopic retroperitoneal lymph node dissection is a safe procedure with low complication rate and with perioperative outcomes comparable with open surgery [35].

The consensus of the authors is that open or laparoscopic retroperitoneal lymph node dissec‐ tion should be concentrated in dedicated referral centers. Thus laparoscopic lymph node resection might be indicated in: low-risk stages, if primary tumor contains mature teratoma or if the primary nonseminomatous germ cell tumor is marker negative. Laparoscopic retroperitoneal lymph node dissection represents a valuable tool for selected patients with clinical stage I. Further studies should focus on the curative potential of the procedures as well as on the role of post chemotherapy [33,34].

Laparoendoscopic single-site and natural orifice transluminal endoscopic in Urology onco‐ logic surgery. To minimize minimal invasive surgery.

Natural orifice transluminal endoscopic surgery (NOTES) and laparoendoscopic single-site surgery (LESS) have been developed to reduce morbidity and scarring. NOTES uses existing orifices of the human body to perform surgical or diagnostic techniques. The use of accessory transabdominal ports as a part of evolution of NOTES is defined as *hybrid* NOTES. LESS procedure implies only a single-port or a single-incision laparoscopy [38].

LESSsurgerywasperformedinseveraloncologicprocedures,sucharadicalnephrectomy,radical prostatectomy,nephroureterectomyandradicalcystectomy.Cumulativeseriesshowingresults have been published. LESS has shown to be feasible (in expert hands) offering patient satisfac‐ tion and shortened convalescence applied to nephrectomy and radical prostatectomy. Patient selection is the most important to minimizing complication and conversion rates [38].

[2] Bishoff, J. T. Kavoussi. Atlas of laparoscopic Urologic Surgery. Prologue. Bishoff JT,

Laparoscopic Surgery in Genitourinary Cancer Treatment

http://dx.doi.org/10.5772/55448

159

[3] Maclennan, S, Imamura, M, Lapitan, M. C, Omar, M. I, Lam, T. B, Hilvano-cabung‐ cal, A. M, et al. UCAN Systematic Review Reference Group. Systematic Review of Perioperative and Quality-of-life Outcomes Following Surgical Management of Lo‐

[4] Maclennan, S, Imamura, M, Lapitan, M. C, Omar, M. I, Lam, T. B, Hilvano-cabung‐ cal, A. M, et al. UCAN Systematic Review Reference Group. Systematic review of on‐ cological outcomes following surgical management of localized renal cancer. Eur

[5] Weight, C. J, Larson, B. T, Fergany, A. F, et al. Nephrectomy induced chronic renal insufficiency is associated with increased risk of cardiovascular death and death from any cause in patients with localized cT1b renal masses. J Urol (2010). , 183,

[6] Porpiglia, F, Fiori, C, Bertolo, R, Morra, I, Russo, R, Piccoli, G, et al. Long-term func‐ tional evaluation of the treated kidney in a prospective series of patients who under‐ went laparoscopic partial nephrectomy for small renal tumors. Eur Urol. (2012). Jul;,

[7] Gill, I. S, Matin, S. F, Desai, M. M, et al. Comparative analysis of laparoscopic versus open partial nephrectomy for renal tumors in 200 patients. J Urol. (2003). , 170, 64-8.

[8] Desai, M. M, Strzempkowski, B, Matin, S. F, Steinberg, A. P, Ng, C, Meraney, A. M, Kaouk, J. H, & Gill, I. S. Prospective randomized comparison of transperitoneal ver‐ sus retroperitoneal laparoscopic radical nephrectomy. J Urol. (2005). Jan;, 173(1),

[9] Lane, B. R, & Gill, I. S. year oncological outcomes after laparoscopic and open partial

[10] Gill, I. S, Kavoussi, L. R, Lane, B. R, Blute, M. L, Babineau, D, Colombo, J. R, et al. Comparison of 1,800 laparoscopic and open partial nephrectomies for single renal tu‐

[11] Marszalek, M, Meixl, H, Polajnar, M, Rauchenwald, M, Jeschke, K, & Madersbacher, S. Laparoscopic and open partial nephrectomy: a matched-pair comparison of 200

[12] Simmons, M. N, Chung, B. I, & Gill, I. S. Perioperative efficacy of laparoscopic partial nephrectomy for tumors larger than 4 cm. Eur Urol. (2009). Jan;, 55(1), 199-207.

[13] Tsivian, M, Ulusoy, S, Abern, M, Wandel, A, Sidi, A. A, & Tsivian, A. Renal Mass Anatomic Characteristics and Perioperative Outcomes of Laparoscopic Partial Neph‐

rectomy: A Critical Analysis. J Endourol. (2012). Jul 30. [Epub ahead of print]

nephrectomy. J Urol. (2010). Feb;, 183(2), 473-9.

patients. Eur Urol. (2009). May;, 55(5), 1171-8.

mors. J Urol. (2007). Jul;, 178(1), 41-6.

calised Renal Cancer. Eur Urol. (2012). Jul 20. [Epub ahead of print]

Kavoussi:Elsevier Masson;(2008). Barcelona.Spain.13.

Urol. (2012). , 61, 972-993.

1317-23.

62(1), 130-5.

38-41.

Comparative series between conventional laparoscopy and LESS have been demonstrated that there were only differences about cosmetic results when LESS was applied to perform radical nephrectomy. Also, there were no differences concerning analgesia and hospital stay. So far, all the comparative series fall to offer large number of cases, and they were retrospective and norandomized [38].

About hybrid NOTES applied to oncologic surgery, the most commonly procedure performed was transvaginal radical nephrectomy. Vaginal access was only used to insert a deflectable camera, whereas two additional abdominal trocars were used as main working ports for instrumentation. Currently, there are few papers with short number of cases and it requires clinical and external validation [38].

LESS has proved to be immediately applicable in the clinical practicum, but requires a skilled laparoscopic surgeon and well-selected patients. The current benefits of LESS are limited to improve cosmetic results [39]. About NOTES, the question is whether women would prefer a transvaginal access; there were studies published that showed a negative / neutral opinion of nulliparous younger women, concerning about the effect of NOTES on sexual function [38,40].

In the future, it is important to perform a standard evaluation of cosmetic results, to design prospective series combining LESS and NOTES as well as improving laparoscopic ergonomics and instrumental [40].

### **Acknowledgements**

To Katherinne Eloise, Katherine Julia, José Jr. and my parents.

### **Author details**

March Villalba José Antonio

European Board of Urology , Hospital Clínico Universitario de Valencia, Spain

### **References**

[1] European Association of Urology guidelines 2012ed. http://www.uroweb.org/guide‐ lines/online-guidelines/.

[2] Bishoff, J. T. Kavoussi. Atlas of laparoscopic Urologic Surgery. Prologue. Bishoff JT, Kavoussi:Elsevier Masson;(2008). Barcelona.Spain.13.

LESSsurgerywasperformedinseveraloncologicprocedures,sucharadicalnephrectomy,radical prostatectomy,nephroureterectomyandradicalcystectomy.Cumulativeseriesshowingresults have been published. LESS has shown to be feasible (in expert hands) offering patient satisfac‐ tion and shortened convalescence applied to nephrectomy and radical prostatectomy. Patient

Comparative series between conventional laparoscopy and LESS have been demonstrated that there were only differences about cosmetic results when LESS was applied to perform radical nephrectomy. Also, there were no differences concerning analgesia and hospital stay. So far, all the comparative series fall to offer large number of cases, and they were retrospective and

About hybrid NOTES applied to oncologic surgery, the most commonly procedure performed was transvaginal radical nephrectomy. Vaginal access was only used to insert a deflectable camera, whereas two additional abdominal trocars were used as main working ports for instrumentation. Currently, there are few papers with short number of cases and it requires

LESS has proved to be immediately applicable in the clinical practicum, but requires a skilled laparoscopic surgeon and well-selected patients. The current benefits of LESS are limited to improve cosmetic results [39]. About NOTES, the question is whether women would prefer a transvaginal access; there were studies published that showed a negative / neutral opinion of nulliparous younger women, concerning about the effect of NOTES on sexual function [38,40]. In the future, it is important to perform a standard evaluation of cosmetic results, to design prospective series combining LESS and NOTES as well as improving laparoscopic ergonomics

selection is the most important to minimizing complication and conversion rates [38].

norandomized [38].

and instrumental [40].

**Acknowledgements**

**Author details**

**References**

March Villalba José Antonio

lines/online-guidelines/.

To Katherinne Eloise, Katherine Julia, José Jr. and my parents.

European Board of Urology , Hospital Clínico Universitario de Valencia, Spain

[1] European Association of Urology guidelines 2012ed. http://www.uroweb.org/guide‐

clinical and external validation [38].

158 Cancer Treatment - Conventional and Innovative Approaches


[14] Mattar, K, & Finelli, A. Expanding the indications for laparoscopic radical nephrecto‐ my. Curr Opin Urol. (2007). Mar;, 17(2), 88-92.

[26] Nix, J, Smith, A, Kurpad, R, Nielsen, M. E, Wallen, E. M, & Pruthi, R. S. Prospective randomized controlled trial of robotic versus open radical cystectomy for bladder cancer: perioperative and pathologic results. Eur Urol. (2010). Feb;, 57(2), 196-201.

Laparoscopic Surgery in Genitourinary Cancer Treatment

http://dx.doi.org/10.5772/55448

161

[27] Haber, G. P, Crouzet, S, & Gill, I. S. Laparoscopic and robotic assisted radical cystec‐ tomy for bladder cancer: a critical analysis. Eur Urol. (2008). Jul;, 54(1), 54-62.

[28] Hautmann, R. E. The oncologic results of laparoscopic radical cystectomy are not (yet) equivalent to open cystectomy. Curr Opin Urol. (2009). Sep;, 19(5), 522-6.

[29] Tanaka, K, Hara, I, Takenaka, A, Kawabata, G, & Fujisawa, M. Incidence of local and port site recurrence of urologic cancer after laparoscopic surgery. Urology. (2008).

[30] Rouprêt, M, Zigeuner, R, Palou, J, Boehle, A, Kaasinen, E, Sylvester, R, et al. Europe‐ an guidelines for the diagnosis and management of upper urinary tract urothelial cell

[31] Ristau, B. T, Tomaszewski, J. J, & Ost, M. C. Upper tract urothelial carcinoma. Cur‐

[32] Albers, P, Albrecht, W, Algaba, F, Bokemeyer, C, Cohn-cedermark, G, Fizazi, K, et al. Testicular cancer guidelines. European guidelines (2011). Avaiable at: http://

[33] Öztürk, Ç, Van Ginkel, R. J, Krol, R. M, Gietema, J. A, Hofker, H. S, & Hoekstra, H. J. Laparoscopic resection of a residual retroperitoneal tumor mass of nonseminomatos

[34] Rassweiler, J. J, Scheitlin, W, Heidenreich, A, Laguna, M. P, & Janetschek, G. Laparo‐ scopic retroperitoneal lymph node dissection: does it still have a role in the manage‐ ment of clinical stage I nonseminomatous testis cancer? A European perspective.

[35] Hyams, E. S, Pierorazio, P, Proteek, O, Sroka, M, Kavoussi, L. R, & Allaf, M. E. Lapa‐ roscopic retroperitoneal lymph node dissection for clinical stage I nonseminomatous

[36] Steiner, H, Zangerl, F, Stöhr, B, Granig, T, Ho, H, Bartsch, G, et al. Results of bilateral nerve sparing laparoscopic retroperitoneal lymph node dissection for testicular can‐

[37] Arai, Y, Kaiho, Y, Yamada, S, Saito, H, Mitsuzuka, K, Yamashita, S, et al. Extraperito‐ neal laparoscopic retroperitoneal lymph node dissection after chemotherapy for non‐ semonimatous testicular germ-cell tumor:surgical and oncological outcomes. Int Urol

[38] Autorino, R, Cadeddu, J. A, Desai, M. M, Gettman, M, Gill, I. S, Kavoussi, L. R, et al. Laparoendoscopic single-site and natural orifice transluminal endoscopic surgery in

urology: a critical analysis of the literature. Eur Urol (2011). , 59, 26-45.

germ cell tumor: a large single institution experience. J Urol (2012). , 487-92.

carcinomas: (2011). update. Eur Urol. 2011;, 59, 584-94.

rent treatment and outcomes. Urology (2012). , 4, 749-56.

www.uroweb.org/gls/pdf/10\_Testicular\_Cancer.pdf.

testicular germ cell tumors. Surg Endosc (2012). , 26, 458-67.

Apr;, 71(4), 728-34.

cer. J Urol (2008). , 1348-53.

Nephrol (2012).


[26] Nix, J, Smith, A, Kurpad, R, Nielsen, M. E, Wallen, E. M, & Pruthi, R. S. Prospective randomized controlled trial of robotic versus open radical cystectomy for bladder cancer: perioperative and pathologic results. Eur Urol. (2010). Feb;, 57(2), 196-201.

[14] Mattar, K, & Finelli, A. Expanding the indications for laparoscopic radical nephrecto‐

[15] Canda, A. E, & Kirkali, Z. Current management of renal cell carcinoma and targeted

[16] Heidenreich, A, Bastian, P. J, Bellmunt, J, Bolla, M, Joniau, S, Mason, M. D, Matveev, V, et al. Guidelines of prostate cáncer. Avaible at: http://www.uroweb.org/gls/pdf/

[17] Ficarra, V, Novara, G, Artibani, W, Cestari, A, Galfano, A, Graefen, M, et al. Retropu‐ bic, laparoscopic, and robot-assisted radical prostatectomy: a systematic review and cumulative analysis of comparative studies..Eur Urol. (2009). May;, 55(5), 1037-63.

[18] Ghavamian, R, Knoll, A, Boczko, J, & Melman, A. Comparison of operative and func‐ tional outcomes of laparoscopic radical prostatectomy and radical retropubic prosta‐

[19] Remzi, M, Klingler, H. C, Tinzl, M. V, Fong, Y. K, Lodde, M, Kiss, B, & Marberger, M. Morbidity of laparoscopic extraperitoneal versus transperitoneal radical prostatecto‐ my verus open retropubic radical prostatectomy. Eur Urol. (2005). Jul;, 48(1), 83-9.

[20] Guazzoni, G, Cestari, A, Naspro, R, Riva, M, Centemero, A, Zanoni, M, et al. Intraand peri-operative outcomes comparing radical retropubic and laparoscopic radical prostatectomy: results from a prospective, randomised, single-surgeon study. Eur

[21] Magheli, A, Gonzalgo, M. L, Su, L. M, Guzzo, T. J, Netto, G, Humphreys, E. B, et al. Impact of surgical technique (open vs laparoscopic vs robotic-assisted) on pathologi‐ cal and biochemical outcomes following radical prostatectomy: an analysis using

[22] Van Velthoven, R. F. Laparoscopic radical prostatectomy: transperitoneal versus ret‐ roperitoneal approach: is there an advantage for the patient? Curr Opin Urol. (2005).

[23] Stenzl, A, Witjes, J. A, Compérat, E, Cowan, N. C, De Santis, M, Kuczyk, M, Lebret, T, Ribal, M. J, et al. European urology Guidelines on Bladder Cancer Muscle-invasive and Metastatic. Avaiable in: http://www.uroweb.org/gls/pdf/07\_Bladder%20Can‐

[24] Challacombe, B. J, Bochner, B. H, Dasgupta, P, Gill, I, Guru, K, Herr, H, et al. The role of laparoscopic and robotic cystectomy in the management of muscle-invasive blad‐ der cancer with special emphasis on cancer control and complications. Eur Urol.

[25] Chade, D. C, Laudone, V. P, Bochner, B. H, & Parra, R. O. Oncological outcomes after radical cystectomy for bladder cancer: open versus minimally invasive approaches. J

propensity score matching. BJU Int. (2011). Jun;, 107(12), 1956-62.

tectomy: single surgeon experience. Urology. (2006). Jun;, 67(6), 1241-6.

08%20Prostate%20Cancer\_LR%20March%(2013). th%202012.pdf).

my. Curr Opin Urol. (2007). Mar;, 17(2), 88-92.

therapy. Urol J. (2006). Winter;, 3(1), 1-14.

160 Cancer Treatment - Conventional and Innovative Approaches

Urol. (2006). Jul;, 50(1), 98-104.

Mar;, 15(2), 83-8.

cer\_LR%20II.pdf

(2011). Oct;, 60(4), 767-75.

Urol. (2010). Mar;, 183(3), 862-69.


[39] Oh, T. H. Current status of laparoscopic single-site surgery in urologic surgery. Kor J Urol (2012). , 53, 443-50.

**Chapter 7**

**Current Strategies in the Management of**

In 2012, rectal cancer affected 40,290 Americans. Colon and rectal cancer resulted in a mortality of 51,690 individuals during the same year [1]. Patients affected with rectal cancer who have a clinical stage II (T3-T4, NO, MO) or III (Any T, N1-N3, M0) tumor are treated with preoperative chemoradiation (CRT) followed by surgical intervention 5-10 weeks after the last CRT treatment. An adequate oncologic operation involves removal of the tumor and the entire mesorectum (total mesorectal excision). This has been demonstrated to decrease local recur‐ rence substantially as the lymphatic drainage of the rectum is contained within the investing fascia (mesorectum). Distal rectal tumors involving the anorectal sphincter complex are classically treated with an abdominoperineal resection (APR); whereas, more proximal tumors might be treated with an anterior protosigmoidectomy with a primary colorectal anastomosis (LAR). There has been a substantial shift in the number of APR operations to LAR procedures over the past decade owing to the implementation of new circular stapling devices and the use

In a Cochrane review of 19 clinical trials assessing preoperative radiotherapy *vs.* surgery alone, the rectum was alternatively defined as below the sacral promontory in three studies, below the pelvic brim in one study, and by the distance from the anal verge in several studies: 12 cm (one study), 13 cm (one study), 14 cm (one study), 15 cm (five studies), and 16 cm (one study) [2]. The hazard ratio for recurrence in patients receiving radiotherapy was less if tumors were located within five to 10 cm from the anal verge, but there was no difference in local recurrence

and reproduction in any medium, provided the original work is properly cited.

© 2013 Huerta and Dineen; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

**Adenocarcinoma of the Rectum**

Additional information is available at the end of the chapter

Sergio Huerta and Sean P. Dineen

http://dx.doi.org/10.5772/55827

**1. Introduction**

of neoadjuvant CRT.

**2. The rectum**


### **Chapter 7**

### **Current Strategies in the Management of Adenocarcinoma of the Rectum**

Sergio Huerta and Sean P. Dineen

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/55827

### **1. Introduction**

[39] Oh, T. H. Current status of laparoscopic single-site surgery in urologic surgery. Kor J

[41] Edge, S. B, Byrd, D. R, Compton, C. C, Fritz, A. G, Greene, F. I, & Trotti, A. Kid‐ ney.Cancer staging handbook AJCC. Seventh ed. Chicago IL: Springer; (2010). , 73-86.

[42] Edge, S. B, Byrd, D. R, Compton, C. C, Fritz, A. G, & Greene, F. I. Trotti A Prostate. Cancer staging handbook AJCC. Seventh ed. Chicago IL: Springer; (2010). , 51-64. [43] Edge, S. B, Byrd, D. R, Compton, C. C, Fritz, A. G, Greene, F. I, & Trotti, A. Urinary Bladder Cancer staging handbook AJCC. Seventh ed. Chicago IL: Springer; (2010). ,

[44] Edge, S. B, Byrd, D. R, Compton, C. C, Fritz, A. G, Greene, F. I, & Trotti, A. Renal pelvis and Ureter Cancer staging handbook AJCC. Seventh ed. Chicago IL: Springer;

[40] Rassweiler, J. J. Is LESS/NOTES relay more? Eur Urol (2011). , 59, 46-50.

Urol (2012). , 53, 443-50.

162 Cancer Treatment - Conventional and Innovative Approaches

95-103.

(2010). , 87-93.

In 2012, rectal cancer affected 40,290 Americans. Colon and rectal cancer resulted in a mortality of 51,690 individuals during the same year [1]. Patients affected with rectal cancer who have a clinical stage II (T3-T4, NO, MO) or III (Any T, N1-N3, M0) tumor are treated with preoperative chemoradiation (CRT) followed by surgical intervention 5-10 weeks after the last CRT treatment. An adequate oncologic operation involves removal of the tumor and the entire mesorectum (total mesorectal excision). This has been demonstrated to decrease local recur‐ rence substantially as the lymphatic drainage of the rectum is contained within the investing fascia (mesorectum). Distal rectal tumors involving the anorectal sphincter complex are classically treated with an abdominoperineal resection (APR); whereas, more proximal tumors might be treated with an anterior protosigmoidectomy with a primary colorectal anastomosis (LAR). There has been a substantial shift in the number of APR operations to LAR procedures over the past decade owing to the implementation of new circular stapling devices and the use of neoadjuvant CRT.

### **2. The rectum**

In a Cochrane review of 19 clinical trials assessing preoperative radiotherapy *vs.* surgery alone, the rectum was alternatively defined as below the sacral promontory in three studies, below the pelvic brim in one study, and by the distance from the anal verge in several studies: 12 cm (one study), 13 cm (one study), 14 cm (one study), 15 cm (five studies), and 16 cm (one study) [2]. The hazard ratio for recurrence in patients receiving radiotherapy was less if tumors were located within five to 10 cm from the anal verge, but there was no difference in local recurrence

© 2013 Huerta and Dineen; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

in patients treated with combination radiotherapy and surgery *vs.* surgery alone in patients that had tumors 10.1 cm from the anal verge [3]. Thus, the benefit of radiotherapy appears to be for more distal tumors (0-10 cm from the anal verge). For the purpose of selecting patient to receive pre-operative CRT, practice guide lines in the United States by the National Cancer Institute (NCI) [4]and the National Comprehensive Cancer Network (NCCN) [5] have defined the rectum to be 12 cm from the anal verge.

Because only stage II and III tumors are treated with pre-operative CRT, clinical staging is pivotal in guiding treatment options. There are currently two modalities to assess tumor stage (T stage) in the pre-operative setting: (1) endorectal ultrasound (EUS) and (2) Magnetic Resonance Imaging (MRI). The efficacy of these modalities has been assessed by two metaanalyses [10;11]. One study favors EUS [10] and the other MRI [11]. In the first analysis, 90 studies were included and assessed the accuracy of EUS, MRI, and CT in pre-operatively staging rectal cancer. The results demonstrated that EUS and MRI were similar in terms of sensitivity (Sn) with regards to tumor depth into the muscularis propia (94%). EUS was superior in determining muscularis propia invasion [specificity (Sp) of 86%] compared to MRI (Sp = 69%) and was an overall sensitive strategy (Sn = 90%) for perirectal tumor invasion compared to MRI (Sn = 82%) [10]. A second meta-analysis interrogated 84 studies. This study showed no difference in these modalities in evaluating the nodes (N-staging) [11]. In seven studies, MRI was a superior strategy in evaluating involved circumferential margins [11]. MRI seems to be emerging as a preferred modality for the assessment of rectal cancer staging in the pre-operative setting. However, the use of either of these modalities is largely based on institutional experience. The sensitivity of EUS following CRT is less compared to virgin tissue.

Current Strategies in the Management of Adenocarcinoma of the Rectum

http://dx.doi.org/10.5772/55827

165

Thus, MRI may be a preferred modality to determine response to neoadjuvant CRT.

The management of stage II and stage III rectal cancer is a tri-modality approach (Radiother‐ apy, Chemotherapy and Surgery) and patients are best managed following discussion at a

Initial studies evaluated the efficacy of radiotherapy without pre-operative chemotherapy. The data has been summarized in two meta-analyses addressing the benefit of preoperative radiation [12;13]. While the data on overall survival was not clear in these analyses, there was a clear decrease in the rate of local recurrence (46% in patients receiving preoperative radiation vs. 53% in the control group). These data established the benefits of preoperative radiotherapy

In Europe, small fractions of ionizing radiation 5.0 Grey (Gy) X 5.0 (over five days), for a total of 25.0 Gy without chemotherapy, are employed. With this strategy, the Swedish Rectal Cancer Trial found an improved rate of survival at five years with preoperative radiation [14]. In the United States, the typical IR dose is 45.0 to 50.4 Gy given in small doses (1.8 Gy/day) for five to six weeks [5]. In contrast to short course radiotherapy, in the United States, long course radiotherapy is given in combination with neoadjuvant chemotherapy. The interval between completion of radiation and subsequent operation is an area of some debate (see below) but

**5. Neoadjuvant chemoradiotherapy**

*5.1.1. Short course vs. long course radiotherapy*

multidisciplinary conference.

**5.1. Radiotherapy**

followed by surgery.

is typically 5-10 weeks.

### **3. Indications for neoadjuvant chemoradiation**

The addition of preoperative radiation therapy to TME decreases locoregional recurrence from approximately 8% to 2%. The combination of chemotherapy and radiation (CRT) further decreases local recurrence. Chemotherapy also increases the number of patients which achieve a pathologic complete response (pCR), i.e. no detectable tumor after resection. This modality also reduces tumor burden in some patients and might allow a sphincter preserving operation (i.e. LAR) as opposed to an APR, allowing a patient to avoid a permanent colostomy. The rate of pCR is approximately 25% [6;7]. Patients who achieve pCR have better long-term outcomes compared to patients who only have a partial response or no response at all [8]. Current guide lines in the United States [4;5] dictate that patients with stage II (T3-T4) or stage III (any T with positive regional lymph nodes) should be treated with neoadjuvant CRT. Patients with stage I (T1-T2) disease or those with distant metastases (stage IV) generally do not receive neoad‐ juvant CRT. However, in instances of synchronous liver metastases for which liver resection is planned, neoadjuvant radiation may be considered. These recommendations emanate from the low rate of recurrence (4%) in patients with stage I tumors treated with surgery alone [9]. Further, there is no difference in the rate of locoregional recurrence in patients with stage IV tumors treated with radiotherapy and surgery compared to palliative surgery alone [3]. Similarly, there is no difference in outcomes in patients with distant metastases treated with neoadjuvant radiotherapy and surgery *vs.* palliative surgery alone [3]. Thus, the standard care of practice is to provide neoadjuvant CRT in patients with stage II and III rectal tumors.

### **4. Clinical staging of rectal cancer**

Staging of rectal cancer begins with a thorough history and physical examination. The most common symptom of rectal cancer is bright red blood per rectum. Physical examination of the abdomen is important to identify any evidence of liver disease (ascites) or masses. A lymph node examination is important in any patient suspected of having cancer. Rectal examination will reveal distal tumors and is mandatory in the evaluation of patients with colorectal cancers. In such cases information regarding the size, degree of fixation, distance from the anal sphincters is important. In women, a rectovaginal examination may reveal extent of disease. A full colonoscopy is indicated to identify synchronous lesions (present in approximately 5% of cases). Rigid proctoscopy will define the distance of the lesion from the anus and can be critical in cases where the distance from the anus is not clear.

Because only stage II and III tumors are treated with pre-operative CRT, clinical staging is pivotal in guiding treatment options. There are currently two modalities to assess tumor stage (T stage) in the pre-operative setting: (1) endorectal ultrasound (EUS) and (2) Magnetic Resonance Imaging (MRI). The efficacy of these modalities has been assessed by two metaanalyses [10;11]. One study favors EUS [10] and the other MRI [11]. In the first analysis, 90 studies were included and assessed the accuracy of EUS, MRI, and CT in pre-operatively staging rectal cancer. The results demonstrated that EUS and MRI were similar in terms of sensitivity (Sn) with regards to tumor depth into the muscularis propia (94%). EUS was superior in determining muscularis propia invasion [specificity (Sp) of 86%] compared to MRI (Sp = 69%) and was an overall sensitive strategy (Sn = 90%) for perirectal tumor invasion compared to MRI (Sn = 82%) [10]. A second meta-analysis interrogated 84 studies. This study showed no difference in these modalities in evaluating the nodes (N-staging) [11]. In seven studies, MRI was a superior strategy in evaluating involved circumferential margins [11]. MRI seems to be emerging as a preferred modality for the assessment of rectal cancer staging in the pre-operative setting. However, the use of either of these modalities is largely based on institutional experience. The sensitivity of EUS following CRT is less compared to virgin tissue. Thus, MRI may be a preferred modality to determine response to neoadjuvant CRT.

### **5. Neoadjuvant chemoradiotherapy**

The management of stage II and stage III rectal cancer is a tri-modality approach (Radiother‐ apy, Chemotherapy and Surgery) and patients are best managed following discussion at a multidisciplinary conference.

### **5.1. Radiotherapy**

in patients treated with combination radiotherapy and surgery *vs.* surgery alone in patients that had tumors 10.1 cm from the anal verge [3]. Thus, the benefit of radiotherapy appears to be for more distal tumors (0-10 cm from the anal verge). For the purpose of selecting patient to receive pre-operative CRT, practice guide lines in the United States by the National Cancer Institute (NCI) [4]and the National Comprehensive Cancer Network (NCCN) [5] have defined

The addition of preoperative radiation therapy to TME decreases locoregional recurrence from approximately 8% to 2%. The combination of chemotherapy and radiation (CRT) further decreases local recurrence. Chemotherapy also increases the number of patients which achieve a pathologic complete response (pCR), i.e. no detectable tumor after resection. This modality also reduces tumor burden in some patients and might allow a sphincter preserving operation (i.e. LAR) as opposed to an APR, allowing a patient to avoid a permanent colostomy. The rate of pCR is approximately 25% [6;7]. Patients who achieve pCR have better long-term outcomes compared to patients who only have a partial response or no response at all [8]. Current guide lines in the United States [4;5] dictate that patients with stage II (T3-T4) or stage III (any T with positive regional lymph nodes) should be treated with neoadjuvant CRT. Patients with stage I (T1-T2) disease or those with distant metastases (stage IV) generally do not receive neoad‐ juvant CRT. However, in instances of synchronous liver metastases for which liver resection is planned, neoadjuvant radiation may be considered. These recommendations emanate from the low rate of recurrence (4%) in patients with stage I tumors treated with surgery alone [9]. Further, there is no difference in the rate of locoregional recurrence in patients with stage IV tumors treated with radiotherapy and surgery compared to palliative surgery alone [3]. Similarly, there is no difference in outcomes in patients with distant metastases treated with neoadjuvant radiotherapy and surgery *vs.* palliative surgery alone [3]. Thus, the standard care of practice is to provide neoadjuvant CRT in patients with stage II and III rectal tumors.

Staging of rectal cancer begins with a thorough history and physical examination. The most common symptom of rectal cancer is bright red blood per rectum. Physical examination of the abdomen is important to identify any evidence of liver disease (ascites) or masses. A lymph node examination is important in any patient suspected of having cancer. Rectal examination will reveal distal tumors and is mandatory in the evaluation of patients with colorectal cancers. In such cases information regarding the size, degree of fixation, distance from the anal sphincters is important. In women, a rectovaginal examination may reveal extent of disease. A full colonoscopy is indicated to identify synchronous lesions (present in approximately 5% of cases). Rigid proctoscopy will define the distance of the lesion from the anus and can be

the rectum to be 12 cm from the anal verge.

164 Cancer Treatment - Conventional and Innovative Approaches

**4. Clinical staging of rectal cancer**

critical in cases where the distance from the anus is not clear.

**3. Indications for neoadjuvant chemoradiation**

Initial studies evaluated the efficacy of radiotherapy without pre-operative chemotherapy. The data has been summarized in two meta-analyses addressing the benefit of preoperative radiation [12;13]. While the data on overall survival was not clear in these analyses, there was a clear decrease in the rate of local recurrence (46% in patients receiving preoperative radiation vs. 53% in the control group). These data established the benefits of preoperative radiotherapy followed by surgery.

#### *5.1.1. Short course vs. long course radiotherapy*

In Europe, small fractions of ionizing radiation 5.0 Grey (Gy) X 5.0 (over five days), for a total of 25.0 Gy without chemotherapy, are employed. With this strategy, the Swedish Rectal Cancer Trial found an improved rate of survival at five years with preoperative radiation [14]. In the United States, the typical IR dose is 45.0 to 50.4 Gy given in small doses (1.8 Gy/day) for five to six weeks [5]. In contrast to short course radiotherapy, in the United States, long course radiotherapy is given in combination with neoadjuvant chemotherapy. The interval between completion of radiation and subsequent operation is an area of some debate (see below) but is typically 5-10 weeks.

### **5.2. Neoadjuvant chemotherapy**

Preoperative chemotherapy is generally used as a radiosensitizer. The EORTC group demon‐ strated that the addition of chemotherapy (5-FU) to the use of preoperative radiation reduced the risk of local recurrence by approximately 50%, from 17.1% to 8.7%. There was not a significant difference in overall survival in this study. Other trials have shown similar improvements in local control. Based on this data, the most established agent used in the preoperative setting in combination with radiation has been 5-fluorouracil (5-FU). The oral form of 5-FU (Capecitabine) is also being widely used in place of 5-FU with similar results [15]. Several chemotherapeutic agents used for the management of colon cancer in the adjuvant setting and for patients with metastases have been evaluated as possible radiosensitizers. These agents include: irinotecan [16], oxaliplatin [17], bevacizumab [18] and cetuximab [18]. With such strategies, there is still a wide response to ionizing radiation and these agents are not in widespread use at this time.

**6.1. Transabdominal operations**

received neoadjuvant chemoradiation.

**6. Surgery**

*6.1.1. Abdominioperineal Resection (APR)*

possible.

anus is obliterated.

alternative approach.

**6.1. Transabdominal operations**

Two operations are typically performed for rectal cancer. The abdominoperineal resection involves the removal of the distal rectum and perineum with clear tumor radial margins laterally to the pelvic sidewalls. Thus, part of this operation is the creation of a permanent colostomy. A low anterior resection involves the removal of the tumor and the creation of an anastomosis. This might require a temporary loop ileostomy especially in patients that have

An abdominoperineal resection (Figure 1) necessitates a permanent colostomy, which frequently carries negative perception as a drastic change in quality of life for patients. Although a permanent stoma does necessitate some changes for patients, data is emerging that quality of life following an APR is not significantly less than that following an LAR [23]. This is related to the relatively high rate of complications following LAR, including sexual dys‐ function, pain and fecal incontinence. However, an APR is associated with a high rate of perineal wound infections [24]. Furthermore, obtaining clear radial margins is more difficult with an APR compared to an LAR [23;25]. As a result, there is an oncologic advantage in peforming an LAR compared to an APR [25]. Thus, in patients with preserved rectal tone, the

associated with higher rates of pCR, this must be assessed in case-to-case basis [21;22].

For stage II and III patients treated with CRT, surgical intervention must be planned within five to fourteen weeks after the last dose of chemoradiation. Although a longer window between neoadjuvant chemoradiation and operative intervention has been

Current Strategies in the Management of Adenocarcinoma of the Rectum

http://dx.doi.org/10.5772/55827

167

Transabdominal operations (LAR or APR) are the operations of choice for stage II and stage III rectal cancers. For small tumors with a good histology and for a patient with a prohibitive risk of surgical intervention, a transanal approach might be an

Two operations are typically performed for rectal cancer. The abdominoperineal resection involves the removal of the distal rectum and perineum with clear tumor radial margins laterally to the pelvic sidewalls. Thus, part of this operation is the creation of a permanent colostomy. A low anterior resection involves the removal of the tumor and the creation of an anastomosis. This might

Figure 1. Abdominoperineal Resection (APR). The rectal tumor is removed, a permanent colostomy is created and the anus is obliterated.

**6.1.2. Low Anterior Resection (LAR): Total Mesorectal Excision (TME)**

**Figure 1.** Abdominoperineal Resection (APR). The rectal tumor is removed, a permanent colostomy is created and the anus is obliterated. **Figure 1.** Abdominoperineal Resection (APR). The rectal tumor is removed, a permanent colostomy is created and the

An LAR (Figure 2) involves the creation of a primary anastomosis. The area confined within the investing fascia of the rectum and the presacral fascia involves the vascular and lymphatic

*6.1.2. Low Anterior Resection (LAR): Total Mesorectal Excision (TME)*

was 25.0%. This rate has been reduced to 5.0% following the introduction of the TME [26].

An abdominoperineal resection (Figure 1) necessitates a permanent colostomy, which is frequently carries negative perception as a drastic change in quality of life for patients. Although a permanent stoma does necessitate some changes for patients, data is emerging that quality of life following an APR is not significantly less than that following an LAR [23]. This is related to the relatively high rate of complications following LAR, including sexual dysfunction, pain and fecal incontinence. However, an APR is associated with a high rate of perineal wound infections [24]. Furthermore, obtaining clear radial margins is more difficult with an APR compared to an LAR [23;25]. As a result, there is an oncologic advantage in peforming an LAR compared to an APR [25]. Thus, in patients with preserved rectal tone, the operation of choice, is an LAR provided tumor associated factors make this

An APR (Figure 2) involves the creation of a primary anastomosis. The area confined within the investing fascia of the rectum and the presacral fascia involves the vascular and lymphatic structures of the mid-rectum. An en bloc resection of the rectum that circumscribes these structures is termed a TME. Superiorly, the mesorectum is defined at the level of the sacral promontory or the division of the right and left superior hemorrhoideal arteries. The mesorectum extends distally and reduces posteriorly at the level of the investing fasica of the levators (Waldeyer's Fascia). Prior to in the introduction of TME the rate of recurrence for rectal cancer

require a temporary loop ileostomy especially in patients that have received neoadjuvant chemoradiation.

operation of choice, is an LAR provided tumor associated factors make this possible.

**6.1.1. Abdominioperineal Resection (APR)**

### **5.3. Pathologic complete response**

A pathologic complete response (pCR) occurs in patients who undergo resection of the rectum and no residual tumor is identified. Patients who have a pCR demonstrate superior survival than those without. The EORTC 22921 showed an increased rate of pCR in patients who underwent chemoradiotherapy (13.7%) compared to patients who received radiation therapy alone (5.3%). A European trial inclusive of 762 patients receiving preoperative chemoradiation compared to radiation alone, the pCR rate was 11.4% *vs.* 3.6%, respectively [19]. A recent randomized phase II trial assessing combined chemoradiation for rectal cancer showed 28% of patients achieved a pCR. Further, 78% of patients exhibited tumor down staging [20]. Thus, chemotherapy has an additive effect to radiotherapy and has become the standard of care for patient with stage II/III tumors within 12 cm of the anal verge [5].

In the United States current guidelines recommend pre-operative radiation [50.4 Gy] in 25-28 fractions combination with 5-FU infusional or bolus with leucovorin [425 mg/m2 /d] or capecitibine [825 mg/m2 ]. Neoadjuvant treatment is followed by surgery five to ten weeks later. While some investigators have shown that longer periods between neoadjuvant CRT and surgery might be associated with an increase rate of pCR [21], this approach is still under investigation [22].

### **6. Surgery**

For stage II and III patients treated with CRT, surgical intervention must be planned within five to ten weeks after the last dose of chemoradiation. Although a longer window between neoadjuvant chemoradiation and operative intervention has been associated with higher rates of pCR, this must be assessed in case-to-case basis [21;22].

Transabdominal operations (LAR or APR) are the operations of choice for stage II and stage III rectal cancers. For small tumors with a good histology and for a patient with a prohibitive risk of surgical intervention, a transanal approach might be an alternative approach.

dose of chemoradiation. Although a longer window between neoadjuvant chemoradiation and operative intervention has been

### **6.1. Transabdominal operations**

**5.2. Neoadjuvant chemotherapy**

166 Cancer Treatment - Conventional and Innovative Approaches

not in widespread use at this time.

**5.3. Pathologic complete response**

capecitibine [825 mg/m2

investigation [22].

**6. Surgery**

Preoperative chemotherapy is generally used as a radiosensitizer. The EORTC group demon‐ strated that the addition of chemotherapy (5-FU) to the use of preoperative radiation reduced the risk of local recurrence by approximately 50%, from 17.1% to 8.7%. There was not a significant difference in overall survival in this study. Other trials have shown similar improvements in local control. Based on this data, the most established agent used in the preoperative setting in combination with radiation has been 5-fluorouracil (5-FU). The oral form of 5-FU (Capecitabine) is also being widely used in place of 5-FU with similar results [15]. Several chemotherapeutic agents used for the management of colon cancer in the adjuvant setting and for patients with metastases have been evaluated as possible radiosensitizers. These agents include: irinotecan [16], oxaliplatin [17], bevacizumab [18] and cetuximab [18]. With such strategies, there is still a wide response to ionizing radiation and these agents are

A pathologic complete response (pCR) occurs in patients who undergo resection of the rectum and no residual tumor is identified. Patients who have a pCR demonstrate superior survival than those without. The EORTC 22921 showed an increased rate of pCR in patients who underwent chemoradiotherapy (13.7%) compared to patients who received radiation therapy alone (5.3%). A European trial inclusive of 762 patients receiving preoperative chemoradiation compared to radiation alone, the pCR rate was 11.4% *vs.* 3.6%, respectively [19]. A recent randomized phase II trial assessing combined chemoradiation for rectal cancer showed 28% of patients achieved a pCR. Further, 78% of patients exhibited tumor down staging [20]. Thus, chemotherapy has an additive effect to radiotherapy and has become the standard of care for

In the United States current guidelines recommend pre-operative radiation [50.4 Gy] in 25-28 fractions combination with 5-FU infusional or bolus with leucovorin [425 mg/m2

While some investigators have shown that longer periods between neoadjuvant CRT and surgery might be associated with an increase rate of pCR [21], this approach is still under

For stage II and III patients treated with CRT, surgical intervention must be planned within five to ten weeks after the last dose of chemoradiation. Although a longer window between neoadjuvant chemoradiation and operative intervention has been associated with higher rates

Transabdominal operations (LAR or APR) are the operations of choice for stage II and stage III rectal cancers. For small tumors with a good histology and for a patient with a prohibitive

risk of surgical intervention, a transanal approach might be an alternative approach.

]. Neoadjuvant treatment is followed by surgery five to ten weeks later.

/d] or

patient with stage II/III tumors within 12 cm of the anal verge [5].

of pCR, this must be assessed in case-to-case basis [21;22].

Two operations are typically performed for rectal cancer. The abdominoperineal resection involves the removal of the distal rectum and perineum with clear tumor radial margins laterally to the pelvic sidewalls. Thus, part of this operation is the creation of a permanent colostomy. A low anterior resection involves the removal of the tumor and the creation of an anastomosis. This might require a temporary loop ileostomy especially in patients that have received neoadjuvant chemoradiation. **6. Surgery** For stage II and III patients treated with CRT, surgical intervention must be planned within five to fourteen weeks after the last

#### *6.1.1. Abdominioperineal Resection (APR)* associated with higher rates of pCR, this must be assessed in case-to-case basis [21;22].

An abdominoperineal resection (Figure 1) necessitates a permanent colostomy, which frequently carries negative perception as a drastic change in quality of life for patients. Although a permanent stoma does necessitate some changes for patients, data is emerging that quality of life following an APR is not significantly less than that following an LAR [23]. This is related to the relatively high rate of complications following LAR, including sexual dys‐ function, pain and fecal incontinence. However, an APR is associated with a high rate of perineal wound infections [24]. Furthermore, obtaining clear radial margins is more difficult with an APR compared to an LAR [23;25]. As a result, there is an oncologic advantage in peforming an LAR compared to an APR [25]. Thus, in patients with preserved rectal tone, the operation of choice, is an LAR provided tumor associated factors make this possible. Transabdominal operations (LAR or APR) are the operations of choice for stage II and stage III rectal cancers. For small tumors with a good histology and for a patient with a prohibitive risk of surgical intervention, a transanal approach might be an alternative approach. **6.1. Transabdominal operations** Two operations are typically performed for rectal cancer. The abdominoperineal resection involves the removal of the distal rectum and perineum with clear tumor radial margins laterally to the pelvic sidewalls. Thus, part of this operation is the creation of a permanent colostomy. A low anterior resection involves the removal of the tumor and the creation of an anastomosis. This might require a temporary loop ileostomy especially in patients that have received neoadjuvant chemoradiation. **6.1.1. Abdominioperineal Resection (APR)**

is removed, a permanent colostomy is created and the anus is obliterated. **Figure 1.** Abdominoperineal Resection (APR). The rectal tumor is removed, a permanent colostomy is created and the anus is obliterated.

#### Figure 1. Abdominoperineal Resection (APR). The rectal tumor is removed, a permanent colostomy is created and the anus is obliterated. *6.1.2. Low Anterior Resection (LAR): Total Mesorectal Excision (TME)*

possible.

An abdominoperineal resection (Figure 1) necessitates a permanent colostomy, which is frequently carries negative perception as a drastic change in quality of life for patients. Although a permanent stoma does necessitate some changes for patients, data is emerging that quality of life following an APR is not significantly less than that following an LAR [23]. This is related to the An LAR (Figure 2) involves the creation of a primary anastomosis. The area confined within the investing fascia of the rectum and the presacral fascia involves the vascular and lymphatic

**6.1.2. Low Anterior Resection (LAR): Total Mesorectal Excision (TME)**

was 25.0%. This rate has been reduced to 5.0% following the introduction of the TME [26].

relatively high rate of complications following LAR, including sexual dysfunction, pain and fecal incontinence. However, an APR is associated with a high rate of perineal wound infections [24]. Furthermore, obtaining clear radial margins is more difficult with an APR compared to an LAR [23;25]. As a result, there is an oncologic advantage in peforming an LAR compared to an APR [25]. Thus, in patients with preserved rectal tone, the operation of choice, is an LAR provided tumor associated factors make this

An APR (Figure 2) involves the creation of a primary anastomosis. The area confined within the investing fascia of the rectum and the presacral fascia involves the vascular and lymphatic structures of the mid-rectum. An en bloc resection of the rectum that circumscribes these structures is termed a TME. Superiorly, the mesorectum is defined at the level of the sacral promontory or the division of the right and left superior hemorrhoideal arteries. The mesorectum extends distally and reduces posteriorly at the level of the investing fasica of the levators (Waldeyer's Fascia). Prior to in the introduction of TME the rate of recurrence for rectal cancer device.

stapling device.

**Figure 2.** Low Anterior Resection (LAR). The rectum involving the tumor is resected and a primary anastomosis is created with a circular

**Figure 3.** Total Mesorectal Excision (TME). The dotted line represents the line of resection. The tumor is resected and a primary anastomosis is performed **Figure 3.** Total Mesorectal Excision (TIME). The dotted line represents the line of resection. The tumor is resected and a primary anastomosis is performed

structures of the mid-rectum. An en bloc resection of the rectum that circumscribes these structures is termed a TME (Figure 3). Superiorly, the mesorectum is defined at the level of the sacral promontory or the division of the right and left superior hemorrhoideal arteries. The mesorectum extends distally and reduces posteriorly at the level of the investing fasica of the levators (Waldeyer's Fascia). Prior to in the introduction of TME the rate of recur‐ rence for rectal cancer was 25.0%. This rate has been reduced to 5.0% following the introduc‐ tion of the TME [26]. Figure 3. Total Mesorectal Excision (TIME). The dotted line represents the line of resection. The tumor is resected and a primary anastomosis is performed **6.1.3. Proximal margin of resection and level of arterial ligation** No studies have interrogated the length required for proximal resection. Because of the continuity with the colon this is not such a concern. NCI guidelines recommend a 5-cm segment of resection proximal to the tumor [4]. While the inferior mesenteric artery (high ligation) was typically the level of arterial ligation recommended, this practice was associated with a decrease in innervation

rectum involving the tumor is resected and a primary anastomosis is created with a circular stapling device. **Figure 2.** Low Anterior Resection (LAR). The rectum involving the tumor is resected and a primary anastomosis is cre‐ ated with a circular stapling device.

**Figure 2.** Low Anterior Resection (LAR). The

#### Figure 2. Low Anterior Resection (LAR). The rectum involving the tumor is resected and a primary anastomosis is created with a circular stapling device. *6.1.3. Proximal margin of resection and level of arterial ligation*

performed

performed

No studies have interrogated the length required for proximal resection. Because of the continuity with the colon this is not such a concern. NCI guidelines recommend a 5-cm segment

Tumor

**Figure 3.** Total Mesorectal Excision (TME). The dotted line represents the line of resection. The tumor is resected and a primary anastomosis is

Figure 3. Total Mesorectal Excision (TIME). The dotted line represents the line of resection. The tumor is resected and a primary anastomosis is

and perfusion to the anastomosis. The evidence demonstrating that this has a superior oncologic compared to ligation at the level

of resection proximal to the tumor [4]. While the inferior mesenteric artery (high ligation) was typically the level of arterial ligation recommended, this practice was associated with a decrease in innervation and perfusion to the anastomosis. The evidence demonstrating that this has a superior oncologic compared to ligation at the level of the superior rectal artery (low ligation) is lacking. Thus, low ligation has become the preferred strategy [27] (Figure 4).

**Figure 4.** High ligation occurs at the root of the IMA (A). Low ligation occurs at the level of the superior rectal artery (B).

**Figure 4.** High ligation occurs at the root of the IMA (A). Low ligation occurs at the level of the superior rectal ar‐

**A B**

Current Strategies in the Management of Adenocarcinoma of the Rectum

Figure 4. High ligation occurs at the root of the IMA (A). Low ligation occurs at the level of the superior rectal artery (B).

http://dx.doi.org/10.5772/55827

169

**6.2. Laparoscopic surgery for the management of adenocarcinoma of the rectum**

series compared to the "gold-standard" to determine the general applicability of innovative approaches.

towards an increase in complications related to male sexual dysfunction (41% vs. 23%).

Minimally invasive surgery has made laparoscopic resection of rectal cancer possible. However, at this juncture, this procedure remains investigational for the management of rectal cancer [5]. It is currently, recommended to include patients in study protocol to continue to address the benefits of the laparoscopic approach in rectal cancer including: oncologic efficacy, complication rates,

Short term outcomes have not been different in patients treated with the laparoscopic approach compared to the open techniques [28]. Multiple case series reporting laparoscopic TME have documented technical feasibility with satisfactory short term outcomes [29]. While case reports have also reported the ability of a robotic proctectomy [30], these studies need to be replicated in large

In contrast to colon cancer, where laparoscopy has been compared to the open approach [31-33], for rectal cancer these studies are currently needed. The Conventional Versus Laparoscopic-Assisted Surgery in Colorectal Cancer (CLASICC) trial specifically addressed rectal cancer [32]. In this study, the rate of complications was similar. However, the rate of positive CRM was twice in the laparoscopic approach compared to the open technique (12% *vs.* 6%; p=0.19). While this was only a trend and not correlated with an increase in the rate of recurrence, these findings need to be further investigated. Additionally, there was also a trend

A randomized controlled trial [34] and institutional case series [35;36] indicate that the laparoscopic and the open TME have similar oncologic outcomes. More data on the long term outcomes of the laparoscopic approach will be shed with further analysis of the Colon Cancer Laparoscopic or Open Resection (COLOR) II [37] and the and the American College of Surgeons Oncology Group

Thus, the current data suggest that the short-term outcomes of laparoscopic and open surgery are similar. It is crucial to analyze the current data of the available studies carefully as patient selection and the experience of the institution/surgeon are paramount in the current available literature. Long term data regarding oncologic outcome and functional status remain at large, as do data

An alternative treatment for early stage rectal cancers is a transanal excision. Candidates for this approach have small (≤ 3-cm) stage I (T1) tumors located within 8-cm from the anal verge that occupy less than 30% of the circumference of the bowel with good histological features is a transanal removal of the tumor with clear margins. There is a substantial risk for local recurrence with this approach. Local rates of recurrence with the transanal approach *vs.* similarly staged tumors treated with a transabdominal approach is 13.2% *vs.* 2.7%; respectively [39]. Twenty percent of patients with T1 tumors who undergo radical resection are discovered to have lymph node metastases [39]. Patients with rectal cancer treated exclusively by local resection show a rate of

Minimally invasive surgery has made laparoscopic resection of rectal cancer possible. How‐ ever, at this juncture, this procedure remains investigational for the management of rectal cancer [5]. It is currently, recommended to include patients in study protocol to continue to address the benefits of the laparoscopic approach in rectal cancer including: oncologic efficacy,

conversion rates, patient benefit, and cost-effectiveness.

demonstrating patient benefit and cost effectiveness [38].

Short term outcomes have not been different in patients treated with the laparoscopic approach compared to the open techniques [28]. Multiple case series reporting laparoscopic TME have documented technical feasibility with satisfactory short term outcomes [29]. While case reports have also reported the ability of a robotic proctectomy [30], these studies need to be replicated in large series compared to the "gold-standard" to determine the general applicability of

In contrast to colon cancer, where laparoscopy has been compared to the open approach [31-33], for rectal cancer these studies are currently needed. The Conventional Versus Lapa‐ roscopic-Assisted Surgery in Colorectal Cancer (CLASICC) trial specifically addressed rectal cancer [32]. In this study, the rate of complications was similar. However, the rate of positive CRM was twice in the laparoscopic approach compared to the open technique (12% *vs.* 6%; p=0.19). While this was only a trend and not correlated with an increase in the rate of recur‐ rence, these findings need to be further investigated. Additionally, there was also a trend towards an increase in complications related to male sexual dysfunction (41% vs. 23%).

**6.3. Transanal excision** 

trial Z6051 is completed.

**6.2. Laparoscopic surgery for the management of adenocarcinoma of the rectum**

complication rates, conversion rates, patient benefit, and cost-effectiveness.

innovative approaches.

tery (B).

of the superior rectal artery (low ligation) is lacking. Thus, low ligation has become the preferred strategy [27] (Figure 4).

No studies have interrogated the length required for proximal resection. Because of the continuity with the colon this is not such a concern. NCI guidelines recommend a 5-cm segment of resection proximal to the tumor [4]. While the inferior mesenteric artery (high ligation) was typically the level of arterial ligation recommended, this practice was associated with a decrease in innervation and perfusion to the anastomosis. The evidence demonstrating that this has a superior oncologic compared to ligation at the level

of the superior rectal artery (low ligation) is lacking. Thus, low ligation has become the preferred strategy [27] (Figure 4).

**6.1.3. Proximal margin of resection and level of arterial ligation**

series compared to the "gold-standard" to determine the general applicability of innovative approaches.

An alternative treatment for early stage rectal cancers is a transanal excision. Candidates for this approach have small (≤ 3-cm) stage I (T1) tumors located within 8-cm from the anal verge that occupy less than 30% of the circumference of the bowel with good histological features is a transanal removal of the tumor with clear margins. There is a substantial risk for local recurrence with this approach. Local rates of recurrence with the transanal approach *vs.* similarly staged tumors treated with a transabdominal approach is 13.2% *vs.* 2.7%; respectively [39]. Twenty percent of patients with T1 tumors who undergo radical resection are discovered to have lymph node metastases [39]. Patients with rectal cancer treated exclusively by local resection show a rate of

**Figure 4.** High ligation occurs at the root of the IMA (A). Low **Figure 4.** High ligation occurs at the root of the IMA (A). Low ligation occurs at the level of the superior rectal ar‐ tery (B).

ligation occurs at the

Figure 3. Total Mesorectal Excision (TIME). The dotted line represents the line of resection. The tumor is resected and a primary anastomosis is of resection proximal to the tumor [4]. While the inferior mesenteric artery (high ligation) was typically the level of arterial ligation recommended, this practice was associated with a decrease in innervation and perfusion to the anastomosis. The evidence demonstrating that this has a superior oncologic compared to ligation at the level of the superior rectal artery (low ligation) is lacking. Thus, low ligation has become the preferred strategy [27] (Figure 4). Figure 4. High ligation occurs at the root of the IMA (A). Low ligation occurs at the level of the superior rectal artery (B). **6.2. Laparoscopic surgery for the management of adenocarcinoma of the rectum** level of the superior rectal artery (B).

#### No studies have interrogated the length required for proximal resection. Because of the continuity with the colon this is not such a concern. NCI guidelines recommend a 5-cm segment of resection proximal to the tumor [4]. While the inferior mesenteric artery **6.2. Laparoscopic surgery for the management of adenocarcinoma of the rectum** Minimally invasive surgery has made laparoscopic resection of rectal cancer possible. However, at this juncture, this procedure

structures of the mid-rectum. An en bloc resection of the rectum that circumscribes these structures is termed a TME (Figure 3). Superiorly, the mesorectum is defined at the level of the sacral promontory or the division of the right and left superior hemorrhoideal arteries. The mesorectum extends distally and reduces posteriorly at the level of the investing fasica of the levators (Waldeyer's Fascia). Prior to in the introduction of TME the rate of recur‐ rence for rectal cancer was 25.0%. This rate has been reduced to 5.0% following the introduc‐

**Figure 3.** Total Mesorectal Excision (TME). The dotted line represents the line of resection. The tumor is resected and a primary anastomosis is

**Figure 3.** Total Mesorectal Excision (TIME). The dotted line represents the line of resection. The tumor is resected and

**Figure 2.** Low Anterior Resection (LAR). The rectum involving the tumor is resected and a primary anastomosis is created with a circular

Tumor

**6.1.3. Proximal margin of resection and level of arterial ligation**

**Figure 2.** Low Anterior Resection (LAR). The rectum involving the tumor is resected and a primary anastomosis is created with a circular

**Figure 2.** Low Anterior Resection (LAR). The rectum involving the tumor is resected and a primary anastomosis is cre‐

No studies have interrogated the length required for proximal resection. Because of the continuity with the colon this is not such a concern. NCI guidelines recommend a 5-cm segment

Tumor

**Figure 3.** Total Mesorectal Excision (TME). The dotted line represents the line of resection. The tumor is resected and a primary anastomosis is

Figure 3. Total Mesorectal Excision (TIME). The dotted line represents the line of resection. The tumor is resected and a primary anastomosis is

Figure 2. Low Anterior Resection (LAR). The rectum involving the tumor is resected and a primary anastomosis is created with a circular stapling

No studies have interrogated the length required for proximal resection. Because of the continuity with the colon this is not such a concern. NCI guidelines recommend a 5-cm segment of resection proximal to the tumor [4]. While the inferior mesenteric artery (high ligation) was typically the level of arterial ligation recommended, this practice was associated with a decrease in innervation and perfusion to the anastomosis. The evidence demonstrating that this has a superior oncologic compared to ligation at the level

of the superior rectal artery (low ligation) is lacking. Thus, low ligation has become the preferred strategy [27] (Figure 4).

**6.1.3. Proximal margin of resection and level of arterial ligation**

tion of the TME [26].

a primary anastomosis is performed

device.

ated with a circular stapling device.

stapling device.

*6.1.3. Proximal margin of resection and level of arterial ligation*

device.

168 Cancer Treatment - Conventional and Innovative Approaches

stapling device.

performed

performed

performed

performed

(high ligation) was typically the level of arterial ligation recommended, this practice was associated with a decrease in innervation and perfusion to the anastomosis. The evidence demonstrating that this has a superior oncologic compared to ligation at the level of the superior rectal artery (low ligation) is lacking. Thus, low ligation has become the preferred strategy [27] (Figure 4). Minimally invasive surgery has made laparoscopic resection of rectal cancer possible. How‐ ever, at this juncture, this procedure remains investigational for the management of rectal cancer [5]. It is currently, recommended to include patients in study protocol to continue to address the benefits of the laparoscopic approach in rectal cancer including: oncologic efficacy, complication rates, conversion rates, patient benefit, and cost-effectiveness. remains investigational for the management of rectal cancer [5]. It is currently, recommended to include patients in study protocol to continue to address the benefits of the laparoscopic approach in rectal cancer including: oncologic efficacy, complication rates, conversion rates, patient benefit, and cost-effectiveness. Short term outcomes have not been different in patients treated with the laparoscopic approach compared to the open techniques [28]. Multiple case series reporting laparoscopic TME have documented technical feasibility with satisfactory short term outcomes [29]. While case reports have also reported the ability of a robotic proctectomy [30], these studies need to be replicated in large

> Short term outcomes have not been different in patients treated with the laparoscopic approach compared to the open techniques [28]. Multiple case series reporting laparoscopic TME have documented technical feasibility with satisfactory short term outcomes [29]. While case reports have also reported the ability of a robotic proctectomy [30], these studies need to be replicated in large series compared to the "gold-standard" to determine the general applicability of innovative approaches. In contrast to colon cancer, where laparoscopy has been compared to the open approach [31-33], for rectal cancer these studies are currently needed. The Conventional Versus Laparoscopic-Assisted Surgery in Colorectal Cancer (CLASICC) trial specifically addressed rectal cancer [32]. In this study, the rate of complications was similar. However, the rate of positive CRM was twice in the laparoscopic approach compared to the open technique (12% *vs.* 6%; p=0.19). While this was only a trend and not correlated with an increase in the rate of recurrence, these findings need to be further investigated. Additionally, there was also a trend towards an increase in complications related to male sexual dysfunction (41% vs. 23%).

Figure 2. Low Anterior Resection (LAR). The rectum involving the tumor is resected and a primary anastomosis is created with a circular stapling In contrast to colon cancer, where laparoscopy has been compared to the open approach [31-33], for rectal cancer these studies are currently needed. The Conventional Versus Lapa‐ roscopic-Assisted Surgery in Colorectal Cancer (CLASICC) trial specifically addressed rectal cancer [32]. In this study, the rate of complications was similar. However, the rate of positive CRM was twice in the laparoscopic approach compared to the open technique (12% *vs.* 6%; p=0.19). While this was only a trend and not correlated with an increase in the rate of recur‐ rence, these findings need to be further investigated. Additionally, there was also a trend towards an increase in complications related to male sexual dysfunction (41% vs. 23%). A randomized controlled trial [34] and institutional case series [35;36] indicate that the laparoscopic and the open TME have similar oncologic outcomes. More data on the long term outcomes of the laparoscopic approach will be shed with further analysis of the Colon Cancer Laparoscopic or Open Resection (COLOR) II [37] and the and the American College of Surgeons Oncology Group trial Z6051 is completed. Thus, the current data suggest that the short-term outcomes of laparoscopic and open surgery are similar. It is crucial to analyze the current data of the available studies carefully as patient selection and the experience of the institution/surgeon are paramount in the current available literature. Long term data regarding oncologic outcome and functional status remain at large, as do data demonstrating patient benefit and cost effectiveness [38].

**6.3. Transanal excision** 

A randomized controlled trial [34] and institutional case series [35;36] indicate that the laparoscopic and the open TME have similar oncologic outcomes. More data on the long term outcomes of the laparoscopic approach will be shed with further analysis of the Colon Cancer Laparoscopic or Open Resection (COLOR) II [37] and the and the American College of Surgeons Oncology Group trial Z6051 is completed.

The number of recommended nodes to be retrieved to accurately stage tumors is 12 according to the NCCN guidelines [5]. In patients treated with neoadjuvant therapy, the number of nodes resected during surgery is 3-6 less compared to patients treated with surgery alone [41-43]. Thus, care must be taken by the surgeon to remove all involved nodes and by pathology for a

Current Strategies in the Management of Adenocarcinoma of the Rectum

http://dx.doi.org/10.5772/55827

171

The circumferential margin (CRM) is important during pathological assessment of tumors in rectal cancer [44]. The CRM refers to assessment of the non-peritonealized area (bare area) of the rectum created by subperitoneal dissection during surgery. Tumors within 1 mm of the resection margin are defined as having a positive CRM. Additionally discontinuous spread or lymph node involvement within 1mm of the CRM is defined as positive. CRM is a predictor of local recurrence in patients receiving surgery as the only modality of treatment of rectal cancer [25;45]. Patients whose CRM is less that 2 mm have a recurrence rate of 16% compared to 5.8% for patients having a CMR over 2mm. The rate of metastases is also higher in patients with less than 2mm margins vs. greater that 2mm (37.6 vs. 12.7%; respectively) [26]. This observation underscores the importance or radial margins in rectal surgery. Other studies have shown that the CRM is an important predictor of local recurrence, distant metastasis, and overall survival in patients receiving induction CRT compared to patients treated with surgery alone [25]. Thus, pathological evaluation of the resected rectal tumor must include the distance

Pathological tumor response following neoadjuvant therapy is graded from 0 to 3. A grade of 0 indicates complete response without any viable cells; while 3 denotes minimal or no response to treatment. It is important for the pathologist and the surgeon to note the response of CRT after surgery to determine if the current regimens are adequate for the patient population and also to determine the possible aggressiveness of the tumor and plan for adjuvant therapies.

Studies continue to accumulate that document the possibility of observing patients who achieve a clinical complete response following neoadjuvant chemoradiation [46;47]. The first study was reported by Habr-Gama's group in 2004 [46]. In this study, 8% of patients considered to have recurrence had a complete pathological response following surgery. Patients with rectal tumors within 0-7 cm from the anal verge received pre-operative radiotherapy (50.4 Gy)

formed 8 weeks after treatment and included proctoscopy with rectal biopsies. Complete clinical response was defined by the absence of any abnormalities during proctoscopy. A rectal

/d)]. Re-staging was per‐

careful analysis of the specimen.

to the tumor to the closest CRM.

*8.2.2. Determining response to induction chemotherapy*

**9. Clinical Complete Response (cCR)**

and chemotherapy [5-FU (425 mg/m2/d) + folinic acid (20 mg/m2

**8.2. Pathological Inspection of the tumor**

*8.2.1. Circumferential Resection Margin (CRM)*

Thus, the current data suggest that the short-term outcomes of laparoscopic and open surgery are similar. It is crucial to analyze the current data of the available studies carefully as patient selection and the experience of the institution/surgeon are paramount in the current available literature. Long term data regarding oncologic outcome and functional status remain at large, as do data demonstrating patient benefit and cost effectiveness [38].

#### **6.3. Transanal excision**

An alternative treatment for early stage rectal cancers is a transanal excision. Candidates for this approach have small (≤ 3-cm) stage I (T1) tumors located within 8-cm from the anal verge that occupy less than 30% of the circumference of the bowel with good histological features is a transanal removal of the tumor with clear margins. There is a substantial risk for local recurrence with this approach. Local rates of recurrence with the transanal approach *vs.* similarly staged tumors treated with a transabdominal approach is 13.2% *vs.* 2.7%; respectively [39]. Twenty percent of patients with T1 tumors who undergo radical resection are discovered to have lymph node metastases [39]. Patients with rectal cancer treated exclusively by local resection show a rate of local recurrence of 9.7% for T1, 25% for T2, and 38% for T3 cancers [40]. In patients that received systemic chemotherapy after the transanal excision, the local recur‐ rence rate was substantially decreased to: 9.5% for T1, 13.6% for T2, and 13.8% for T3 cancers [40]. This approach is, perhaps, of most benefit in patients with a high operative risk.

### **7. Adjuvant chemotherapy**

Patients with stage II/III rectal cancer should be treated with adjuvant chemotherapy as soon as they are able. Current regimens for this approach extrapolate the experience with colon cancer such that FOLFOX (5-FU/leucovorin, and oxaliplatin) for six months is recommended. 5-FU with or without leucovorin as well as capacitibine with or without oxaliplatin are also alternative options for treatment in the adjuvant setting [5].

### **8. Pathological analysis of rectal cancer**

#### **8.1. Staging**

In rectal cancer staging, the prefix "p" refers to pathological staging and "yp" indicates pathological staging after neoadjuvant chemoradiation.

The number of recommended nodes to be retrieved to accurately stage tumors is 12 according to the NCCN guidelines [5]. In patients treated with neoadjuvant therapy, the number of nodes resected during surgery is 3-6 less compared to patients treated with surgery alone [41-43]. Thus, care must be taken by the surgeon to remove all involved nodes and by pathology for a careful analysis of the specimen.

### **8.2. Pathological Inspection of the tumor**

A randomized controlled trial [34] and institutional case series [35;36] indicate that the laparoscopic and the open TME have similar oncologic outcomes. More data on the long term outcomes of the laparoscopic approach will be shed with further analysis of the Colon Cancer Laparoscopic or Open Resection (COLOR) II [37] and the and the American College of

Thus, the current data suggest that the short-term outcomes of laparoscopic and open surgery are similar. It is crucial to analyze the current data of the available studies carefully as patient selection and the experience of the institution/surgeon are paramount in the current available literature. Long term data regarding oncologic outcome and functional status remain at large,

An alternative treatment for early stage rectal cancers is a transanal excision. Candidates for this approach have small (≤ 3-cm) stage I (T1) tumors located within 8-cm from the anal verge that occupy less than 30% of the circumference of the bowel with good histological features is a transanal removal of the tumor with clear margins. There is a substantial risk for local recurrence with this approach. Local rates of recurrence with the transanal approach *vs.* similarly staged tumors treated with a transabdominal approach is 13.2% *vs.* 2.7%; respectively [39]. Twenty percent of patients with T1 tumors who undergo radical resection are discovered to have lymph node metastases [39]. Patients with rectal cancer treated exclusively by local resection show a rate of local recurrence of 9.7% for T1, 25% for T2, and 38% for T3 cancers [40]. In patients that received systemic chemotherapy after the transanal excision, the local recur‐ rence rate was substantially decreased to: 9.5% for T1, 13.6% for T2, and 13.8% for T3 cancers

[40]. This approach is, perhaps, of most benefit in patients with a high operative risk.

Patients with stage II/III rectal cancer should be treated with adjuvant chemotherapy as soon as they are able. Current regimens for this approach extrapolate the experience with colon cancer such that FOLFOX (5-FU/leucovorin, and oxaliplatin) for six months is recommended. 5-FU with or without leucovorin as well as capacitibine with or without oxaliplatin are also

In rectal cancer staging, the prefix "p" refers to pathological staging and "yp" indicates

Surgeons Oncology Group trial Z6051 is completed.

170 Cancer Treatment - Conventional and Innovative Approaches

**6.3. Transanal excision**

**7. Adjuvant chemotherapy**

**8.1. Staging**

alternative options for treatment in the adjuvant setting [5].

**8. Pathological analysis of rectal cancer**

pathological staging after neoadjuvant chemoradiation.

as do data demonstrating patient benefit and cost effectiveness [38].

### *8.2.1. Circumferential Resection Margin (CRM)*

The circumferential margin (CRM) is important during pathological assessment of tumors in rectal cancer [44]. The CRM refers to assessment of the non-peritonealized area (bare area) of the rectum created by subperitoneal dissection during surgery. Tumors within 1 mm of the resection margin are defined as having a positive CRM. Additionally discontinuous spread or lymph node involvement within 1mm of the CRM is defined as positive. CRM is a predictor of local recurrence in patients receiving surgery as the only modality of treatment of rectal cancer [25;45]. Patients whose CRM is less that 2 mm have a recurrence rate of 16% compared to 5.8% for patients having a CMR over 2mm. The rate of metastases is also higher in patients with less than 2mm margins vs. greater that 2mm (37.6 vs. 12.7%; respectively) [26]. This observation underscores the importance or radial margins in rectal surgery. Other studies have shown that the CRM is an important predictor of local recurrence, distant metastasis, and overall survival in patients receiving induction CRT compared to patients treated with surgery alone [25]. Thus, pathological evaluation of the resected rectal tumor must include the distance to the tumor to the closest CRM.

### *8.2.2. Determining response to induction chemotherapy*

Pathological tumor response following neoadjuvant therapy is graded from 0 to 3. A grade of 0 indicates complete response without any viable cells; while 3 denotes minimal or no response to treatment. It is important for the pathologist and the surgeon to note the response of CRT after surgery to determine if the current regimens are adequate for the patient population and also to determine the possible aggressiveness of the tumor and plan for adjuvant therapies.

### **9. Clinical Complete Response (cCR)**

Studies continue to accumulate that document the possibility of observing patients who achieve a clinical complete response following neoadjuvant chemoradiation [46;47]. The first study was reported by Habr-Gama's group in 2004 [46]. In this study, 8% of patients considered to have recurrence had a complete pathological response following surgery. Patients with rectal tumors within 0-7 cm from the anal verge received pre-operative radiotherapy (50.4 Gy) and chemotherapy [5-FU (425 mg/m2/d) + folinic acid (20 mg/m2 /d)]. Re-staging was per‐ formed 8 weeks after treatment and included proctoscopy with rectal biopsies. Complete clinical response was defined by the absence of any abnormalities during proctoscopy. A rectal scar or a positive biopsy was defined as an incomplete response. These patients did not receive postoperative chemotherapy unless they had recurrent disease. These findings were then reproduced by Maas et al [47].

**Author details**

USA

**References**

Sergio Huerta and Sean P. Dineen

2012; , 62(1), 10-29.

Syst Rev (2007). CD002102.

Netw (2009). , 7(8), 838-881.

(2010). , 42(10), 679-684.

cancer. Surg Oncol (2004).

11(9), 835-844.

Exp Med Biol (2010). , 685, 124-133.

tal cancer. N Engl J Med (2001). , 345(9), 638-646.

University of Texas Southwestern Medical Center and North Texas VA Health Care System,

Current Strategies in the Management of Adenocarcinoma of the Rectum

http://dx.doi.org/10.5772/55827

173

[1] Siegel, R, Naishadham, D, & Jemal, A. Cancer statistics, (2012). CA Cancer J Clin

[2] Wong, R. K, & Tandan, V. De SS, Figueredo A. Pre-operative radiotherapy and cura‐ tive surgery for the management of localized rectal carcinoma. Cochrane Database

[3] Kapiteijn, E, Marijnen, C. A, Nagtegaal, I. D, Putter, H, Steup, W. H, Wiggers, T, et al. Preoperative radiotherapy combined with total mesorectal excision for resectable rec‐

[4] Nelson, H, Petrelli, N, Carlin, A, Couture, J, Fleshman, J, Guillem, J, et al. Guidelines 2000 for colon and rectal cancer surgery. J Natl Cancer Inst (2001). , 93(8), 583-596. [5] Engstrom, P. F, Arnoletti, J. P, & Benson, A. B. III, Chen YJ, Choti MA, Cooper HS et al. NCCN Clinical Practice Guidelines in Oncology: rectal cancer. J Natl Compr Canc

[6] Huerta, S. Rectal cancer and importance of chemoradiation in the treatment. Adv

[7] Huerta, S, Hrom, J, Gao, X, Saha, D, Anthony, T, Reinhart, H, et al. Tissue microarray constructs to predict a response to chemoradiation in rectal cancer. Dig Liver Dis

[8] Maas, M, Nelemans, P. J, Valentini, V, Das, P, Rodel, C, Kuo, L. J, et al. Long-term outcome in patients with a pathological complete response after chemoradiation for rectal cancer: a pooled analysis of individual patient data. Lancet Oncol (2010). ,

[9] Rodel, C, & Sauer, R. Radiotherapy and concurrent radiochemotherapy for rectal

[10] Bipat, S, Glas, A. S, Slors, F. J, Zwinderman, A. H, Bossuyt, P. M, & Stoker, J. Rectal cancer: local staging and assessment of lymph node involvement with endoluminal

US, CT, and MR imaging--a meta-analysis. Radiology (2004). , 232(3), 773-783. [11] Lahaye, M. J, Engelen, S. M, Nelemans, P. J, & Beets, G. L. van de Velde CJ, van En‐ gelshoven JM et al. Imaging for predicting the risk factors--the circumferential resec‐

Maas et al compared patients that achieved a cCR to patients who had a pathological complete response after surgery. Twenty-one subjects were included in the study arm and 20 in the control group. The major differences in these studies include the follow up in Maas vs. Habr-Gama's studies (24.8 *vs.* 57.3 months; respectively). While radiotherapy was similar, Maas used capecitabine rather than 5-FU. Additionally, the definition of cCR was different in these two studies. Habr-Gama used proctoscopy and rectal biopsies while Maas relied on magnetic resonance imaging (MRI), endorectal ultrasound, and biopsies. Finally, all pre-operatively staged III patients received adjuvant chemotherapy consisting of oxaliplatin and capecitabine in Maas study and none in Habr-Gama's.

While there are some differences between the studies by Habr-Gama and Maas, they provide an excellent platform to build on further prospective cohort studies. Further, two other smaller studies have replicated these observations [48;49].

### **10. Complications**

Complications from rectal surgery are typically associated with bladder and sexual dysfunc‐ tion. A TME has been associated with bladder dysfunction (17.8%), loss of erection (27.7%), and lack of ejaculation (33.9%) [50]. Up to 30% of patients with attempted curative surgical intervention will eventually develop regional (pelvic) recurrence [9]. Treatment failure is largely dependent on the cohort of patients studied and combined to patients who develop metastasis, the rate is substantially high.

### **11. Conclusions**

The management of rectal cancer is in dynamic evolution. Drastic improvements have occurred over the past 20 years. However, the 5-year survival for these patients remains unacceptably high. The tri-modality approach has demonstrated clear advantages. In a small segment of patients (~25%) the tri-modality approach might be reduced to a bimodality treatment avoiding surgery in patients that achieve a clinical complete response. However, this strategy should be undertaken only in the setting of an Institutional Board Review protocol. Efforts to improve local control and survival in rectal cancer are continuing in multiple clinical and preclinical studies. An understanding of specific molecular pathways leading to a response in neoadjuvant modalities will refine the segment of patients who might need an operation sooner compared to patients who might be observed. Ongoing trials on the laparoscopic approach for rectal cancer will shed light into the benefits of this practice.

### **Author details**

scar or a positive biopsy was defined as an incomplete response. These patients did not receive postoperative chemotherapy unless they had recurrent disease. These findings were then

Maas et al compared patients that achieved a cCR to patients who had a pathological complete response after surgery. Twenty-one subjects were included in the study arm and 20 in the control group. The major differences in these studies include the follow up in Maas vs. Habr-Gama's studies (24.8 *vs.* 57.3 months; respectively). While radiotherapy was similar, Maas used capecitabine rather than 5-FU. Additionally, the definition of cCR was different in these two studies. Habr-Gama used proctoscopy and rectal biopsies while Maas relied on magnetic resonance imaging (MRI), endorectal ultrasound, and biopsies. Finally, all pre-operatively staged III patients received adjuvant chemotherapy consisting of oxaliplatin and capecitabine

While there are some differences between the studies by Habr-Gama and Maas, they provide an excellent platform to build on further prospective cohort studies. Further, two other smaller

Complications from rectal surgery are typically associated with bladder and sexual dysfunc‐ tion. A TME has been associated with bladder dysfunction (17.8%), loss of erection (27.7%), and lack of ejaculation (33.9%) [50]. Up to 30% of patients with attempted curative surgical intervention will eventually develop regional (pelvic) recurrence [9]. Treatment failure is largely dependent on the cohort of patients studied and combined to patients who develop

The management of rectal cancer is in dynamic evolution. Drastic improvements have occurred over the past 20 years. However, the 5-year survival for these patients remains unacceptably high. The tri-modality approach has demonstrated clear advantages. In a small segment of patients (~25%) the tri-modality approach might be reduced to a bimodality treatment avoiding surgery in patients that achieve a clinical complete response. However, this strategy should be undertaken only in the setting of an Institutional Board Review protocol. Efforts to improve local control and survival in rectal cancer are continuing in multiple clinical and preclinical studies. An understanding of specific molecular pathways leading to a response in neoadjuvant modalities will refine the segment of patients who might need an operation sooner compared to patients who might be observed. Ongoing trials on the laparoscopic approach for rectal cancer will shed light into the benefits of this practice.

reproduced by Maas et al [47].

172 Cancer Treatment - Conventional and Innovative Approaches

in Maas study and none in Habr-Gama's.

metastasis, the rate is substantially high.

**10. Complications**

**11. Conclusions**

studies have replicated these observations [48;49].

Sergio Huerta and Sean P. Dineen

University of Texas Southwestern Medical Center and North Texas VA Health Care System, USA

### **References**


tion margin and nodal disease--of local recurrence in rectal cancer: a meta-analysis. Semin Ultrasound CT MR (2005). , 26(4), 259-268.

[26] Machiels, J. P, Sempoux, C, Scalliet, P, Coche, J. C, Humblet, Y, et al. Phase I/II study of preoperative cetuximab, capecitabine, and external beam radiotherapy in patients

Current Strategies in the Management of Adenocarcinoma of the Rectum

http://dx.doi.org/10.5772/55827

175

[27] Lange, M. M, & Buunen, M. van de Velde CJ, Lange JF. Level of arterial ligation in rectal cancer surgery: low tie preferred over high tie. A review. Dis Colon Rectum

[28] Tjandra, J. J, Chan, M. K, & Yeh, C. H. Laparoscopic- vs. hand-assisted ultralow ante‐ rior resection: a prospective study. Dis Colon Rectum (2008). , 51(1), 26-31.

[29] Ng, K. H, Ng, D. C, Cheung, H. Y, Wong, J. C, Yau, K. K, Chung, C. C, et al. Laparo‐ scopic resection for rectal cancers: lessons learned from 579 cases. Ann Surg (2009). ,

[30] Luca, F, Cenciarelli, S, Valvo, M, Pozzi, S, Faso, F. L, Ravizza, D, et al. Full robotic left colon and rectal cancer resection: technique and early outcome. Ann Surg Oncol

[31] A comparison of laparoscopically assisted and open colectomy for colon cancer. N

[32] Guillou, P. J, Quirke, P, Thorpe, H, Walker, J, Jayne, D. G, Smith, A. M, et al. Shortterm endpoints of conventional versus laparoscopic-assisted surgery in patients with colorectal cancer (MRC CLASICC trial): multicentre, randomised controlled trial.

[33] Veldkamp, R, Kuhry, E, Hop, W. C, Jeekel, J, Kazemier, G, Bonjer, H. J, et al. Laparo‐ scopic surgery versus open surgery for colon cancer: short-term outcomes of a rando‐

[34] Lujan, J, Valero, G, Hernandez, Q, Sanchez, A, Frutos, M. D, & Parrilla, P. Random‐ ized clinical trial comparing laparoscopic and open surgery in patients with rectal

[35] Laurent, C, Leblanc, F, Wutrich, P, Scheffler, M, & Rullier, E. Laparoscopic versus open surgery for rectal cancer: long-term oncologic results. Ann Surg (2009). , 250(1),

[36] Milsom, J. W. de OO, Jr., Trencheva KI, Pandey S, Lee SW, Sonoda T. Long-term out‐ comes of patients undergoing curative laparoscopic surgery for mid and low rectal

[37] Buunen, M, Bonjer, H. J, Hop, W. C, Haglind, E, Kurlberg, G, Rosenberg, J, et al. COLOR II. A randomized clinical trial comparing laparoscopic and open surgery for

[38] Wagman, L. D. Laparoscopic and open surgery for colorectal cancer: reaching equi‐

with rectal cancer. Ann Oncol (2007). , 18(4), 738-744.

(2008). , 51(7), 1139-1145.

(2009). , 16(5), 1274-1278.

Engl J Med 2004; 350(20):2050-2059.

Lancet (2005). , 365(9472), 1718-1726.

cancer. Br J Surg (2009). , 96(9), 982-989.

mised trial. Lancet Oncol (2005). , 6(7), 477-484.

cancer. Dis Colon Rectum (2009). , 52(7), 1215-1222.

rectal cancer. Dan Med Bull (2009). , 56(2), 89-91.

poise? J Clin Oncol (2007). , 25(21), 2996-2998.

249(1), 82-86.

54-61.


[26] Machiels, J. P, Sempoux, C, Scalliet, P, Coche, J. C, Humblet, Y, et al. Phase I/II study of preoperative cetuximab, capecitabine, and external beam radiotherapy in patients with rectal cancer. Ann Oncol (2007). , 18(4), 738-744.

tion margin and nodal disease--of local recurrence in rectal cancer: a meta-analysis.

[12] Adjuvant radiotherapy for rectal cancer: a systematic overview of 8patients from 22

[13] Camma, C, Giunta, M, Fiorica, F, Pagliaro, L, Craxi, A, & Cottone, M. Preoperative radiotherapy for resectable rectal cancer: A meta-analysis. JAMA (2000). , 284(8),

[14] Improved survival with preoperative radiotherapy in resectable rectal cancerSwed‐

[15] Patel, P. A. Evolution of 5-fluorouracil-based chemoradiation in the management of

[16] Illum, H. Irinotecan and radiosensitization in rectal cancer. Anticancer Drugs (2011). ,

[17] Huerta, S, & Hrom, J. Oxaliplatin as a radiosensitizing agent in rectal cancer. Anti‐

[18] Glynne-jones, R, Mawdsley, S, & Harrison, M. Antiepidermal growth factor receptor radiosensitizers in rectal cancer. Anticancer Drugs (2011). , 22(4), 330-340.

[19] Bosset, J. F, Collette, L, Calais, G, Mineur, L, Maingon, P, Radosevic-jelic, L, et al. Chemotherapy with preoperative radiotherapy in rectal cancer. N Engl J Med

[20] Mohiuddin, M, Winter, K, Mitchell, E, Hanna, N, Yuen, A, Nichols, C, et al. Random‐ ized phase II study of neoadjuvant combined-modality chemoradiation for distal rec‐ tal cancer: Radiation Therapy Oncology Group Trial 0012. J Clin Oncol (2006). , 24(4),

[21] De Campos-lobato, L. F, & Geisler, D. P. da Luz MA, Stocchi L, Dietz D, Kalady MF. Neoadjuvant therapy for rectal cancer: the impact of longer interval between chemo‐

[22] Huerta, S. Interval between neoadjuvant chemoradiation and surgery for the man‐

[23] How, P, Stelzner, S, Branagan, G, Bundy, K, Chandrakumaran, K, Heald, R. J, et al. Comparative quality of life in patients following abdominoperineal excision and low anterior resection for low rectal cancer. Dis Colon Rectum (2012). , 55(4), 400-406.

[24] MacFarlane JKRyall RD, Heald RJ. Mesorectal excision for rectal cancer. Lancet

[25] Nagtegaal, I. D, & Quirke, P. What is the role for the circumferential margin in the

modern treatment of rectal cancer? J Clin Oncol (2008). , 26(2), 303-312.

radiation and surgery. J Gastrointest Surg (2011). , 15(3), 444-450.

agement of rectal cancer. J Gastrointest Surg (2011).

Semin Ultrasound CT MR (2005). , 26(4), 259-268.

174 Cancer Treatment - Conventional and Innovative Approaches

1008-1015.

22(4), 324-329.

650-655.

randomised trials. Lancet (2001). , 358(9290), 1291-1304.

ish Rectal Cancer Trial. N Engl J Med (1997). , 336(14), 980-987.

rectal cancer. Anticancer Drugs (2011). , 22(4), 311-316.

cancer Drugs (2011). , 22(4), 317-323.

(2006). , 355(11), 1114-1123.

(1993). , 341(8843), 457-460.


[39] Nash, G. M, Weiser, M. R, Guillem, J. G, Temple, L. K, Shia, J, Gonen, M, et al. Longterm survival after transanal excision of T1 rectal cancer. Dis Colon Rectum (2009). , 52(4), 577-582.

**Chapter 8**

**Mesothelioma: An Evidence-Based Review**

The initial discovery of mesothelioma can be traced back to 1767 when Dr. Joseph Lieutaud, an anatomy pathologist in France, first identified a tumour in the chest wall of a young boy [1]. Mesothelioma is a rare, aggressive form of cancer that develops from transformed cells originating in the mesothelium, which is the protective lining covering many of the body's internal organs. Mesothelioma arises in the pleura but also occurs in the peritoneum, the tunica vaginalis, and the pericardium [2]. Mesothelioma tends to have a local progression. While disseminated disease has sometimes been reported in a very late stage of the disease [3– 7],

In Canada, there are 459 new reported cases of mesothelioma per year [8], compared to 3,000 in the United States of America. According to Connelly RR et al, the incidence of mesothelioma in the United States is 10 cases per million people per year [9]. Men are more commonly affected than women, with a male predominance of 90%. While there is a correlation between increasing

The number of cases recorded in the Quebec Tumour Database from 1982 to 2002 (for the province of Quebec, Canada; see table 1) reveals that the incidence of pleural and peritoneal mesothelioma was higher for men than women. The overall annual rate of increase from 1982 to 2002 in Quebec was estimated to be 3.6%, which was lower than that measured from 1982 to 1996. In comparison to the international level, only Australia and Scotland showed signifi‐

and reproduction in any medium, provided the original work is properly cited.

© 2013 Goudreault and Dagnault; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

age and reported cases, there is no peak and the mean age at diagnosis is 60 years.

Julie Goudreault and Anne Dagnault

patients usually die from local progression.

cant increases in mesothelioma among women [10].

http://dx.doi.org/10.5772/55292

**1. Introduction**

**2. Incidence**

Additional information is available at the end of the chapter


### **Mesothelioma: An Evidence-Based Review**

Julie Goudreault and Anne Dagnault

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/55292

### **1. Introduction**

[39] Nash, G. M, Weiser, M. R, Guillem, J. G, Temple, L. K, Shia, J, Gonen, M, et al. Longterm survival after transanal excision of T1 rectal cancer. Dis Colon Rectum (2009). ,

[40] Sengupta, S, & Tjandra, J. J. Local excision of rectal cancer: what is the evidence? Dis

[41] Baxter, N. N, Morris, A. M, Rothenberger, D. A, & Tepper, J. E. Impact of preopera‐ tive radiation for rectal cancer on subsequent lymph node evaluation: a population-

[42] Tepper, J. E, Connell, O, Niedzwiecki, M. J, Hollis, D, Compton, D, Benson, C, & Iii, A. B. et al. Impact of number of nodes retrieved on outcome in patients with rectal

[43] Wichmann, M. W, Muller, C, Meyer, G, Strauss, T, Hornung, H. M, Lau-werner, U, et al. Effect of preoperative radiochemotherapy on lymph node retrieval after resection

[44] Compton, C. C. Key issues in reporting common cancer specimens: problems in pathologic staging of colon cancer. Arch Pathol Lab Med (2006). , 130(3), 318-324. [45] Nagtegaal, I. D, Marijnen, C. A, Kranenbarg, E. K, Van D, V, & Van Krieken, J. H. Circumferential margin involvement is still an important predictor of local recur‐ rence in rectal carcinoma: not one millimeter but two millimeters is the limit. Am J

[46] Habr-gama, A, Perez, R. O, Nadalin, W, Sabbaga, J, & Ribeiro, U. Jr., Silva e Sousa AH Jr et al. Operative versus nonoperative treatment for stage 0 distal rectal cancer following chemoradiation therapy: long-term results. Ann Surg (2004). , 240(4),

[47] Maas, M, Beets-tan, R. G, Lambregts, D. M, Lammering, G, Nelemans, P. J, Engelen, S. M, et al. Wait-and-see policy for clinical complete responders after chemoradiation

[48] Dalton, R. S, Velineni, R, Osborne, M. E, Thomas, R, Harries, S, Gee, A. S, et al. A single-centre experience of chemoradiotherapy for rectal cancer: is there potential for

[49] Smith, J. D, Ruby, J. A, Goodman, K. A, Saltz, L. B, Guillem, J. G, Weiser, M. R, et al. Nonoperative management of rectal cancer with complete clinical response after neo‐

[50] Morino, M, Parini, U, Allaix, M. E, Monasterolo, G, Brachet, C. R, & Garrone, C. Male sexual and urinary function after laparoscopic total mesorectal excision. Surg Endosc

based analysis. Int J Radiat Oncol Biol Phys (2005). , 61(2), 426-431.

52(4), 577-582.

176 Cancer Treatment - Conventional and Innovative Approaches

Colon Rectum (2001). , 44(9), 1345-1361.

cancer. J Clin Oncol (2001). , 19(1), 157-163.

Surg Pathol (2002). , 26(3), 350-357.

711-717.

of rectal cancer. Arch Surg (2002). , 137(2), 206-210.

for rectal cancer. J Clin Oncol (2011). , 29(35), 4633-4640.

adjuvant therapy. Ann Surg (2012). , 256(6), 965-972.

(2009). , 23(6), 1233-1240.

nonoperative management? Colorectal Dis (2012). , 14(5), 567-571.

The initial discovery of mesothelioma can be traced back to 1767 when Dr. Joseph Lieutaud, an anatomy pathologist in France, first identified a tumour in the chest wall of a young boy [1]. Mesothelioma is a rare, aggressive form of cancer that develops from transformed cells originating in the mesothelium, which is the protective lining covering many of the body's internal organs. Mesothelioma arises in the pleura but also occurs in the peritoneum, the tunica vaginalis, and the pericardium [2]. Mesothelioma tends to have a local progression. While disseminated disease has sometimes been reported in a very late stage of the disease [3– 7], patients usually die from local progression.

### **2. Incidence**

In Canada, there are 459 new reported cases of mesothelioma per year [8], compared to 3,000 in the United States of America. According to Connelly RR et al, the incidence of mesothelioma in the United States is 10 cases per million people per year [9]. Men are more commonly affected than women, with a male predominance of 90%. While there is a correlation between increasing age and reported cases, there is no peak and the mean age at diagnosis is 60 years.

The number of cases recorded in the Quebec Tumour Database from 1982 to 2002 (for the province of Quebec, Canada; see table 1) reveals that the incidence of pleural and peritoneal mesothelioma was higher for men than women. The overall annual rate of increase from 1982 to 2002 in Quebec was estimated to be 3.6%, which was lower than that measured from 1982 to 1996. In comparison to the international level, only Australia and Scotland showed signifi‐ cant increases in mesothelioma among women [10].

© 2013 Goudreault and Dagnault; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


(2,450 deaths) [24]. Nevertheless, the rate of deaths in Great Britain associated with mesothe‐ lioma is expected to drop significantly after 2015, most likely because of reduced asbestos

Mesothelioma: An Evidence-Based Review http://dx.doi.org/10.5772/55292 179

Although it was once thought that smoking could lead to mesothelioma, we now know that is not the case. It does, however, increase the risk associated with asbestos exposure [25].

Carbon nanotubes are stronger than steel yet lighter than aluminum. As a result, they can be found in a wide range of items such as high-performance bicycle frames, textiles (i.e. water‐ proofing fabrics), body armour, and concrete. Nevertheless, animal studies have demonstrated that carbon nanotubes can produce mesothelioma-like changes and may therefore cause mesothelioma [26,27]. Furthermore, it has been suggested that the mechanism involved may be either attributed to "changes in gene expression, epigenetic changes, and receptor-mediated

Ionizing radiation to supradiaphragmatic fields appears to be a risk factor for developing mesothelioma. Data from patients treated with radiation therapy for Hodgkin's lymphoma [29], non-Hodgkin's lymphoma [30], and testicular cancer [31] revealed an excess rate of mesothelioma. Although the reported number of mesotheliomas was small, the risks were statistically significant. This might be the result of broader radiation therapy for Hodgkin's and non-Hodgkin's lymphoma, since mantle-field radiation had once been the standard method of treatment. Afterwards, extended-field radiation therapy became the standard of care. Since today's preferred method of radiation therapy for lymphomas is involved-field radiation, the incidence of mesotheliomas in patients with Hodgkin's or non-Hodgkin's lymphomas should drop because the smaller radiation-therapy fields should result in fewer secondary neoplasms. Moreover, since mediastinal radiation therapy is no longer given for testicular seminomatous germ-cell tumours, such patients should evidence a decrease in

Another cause for mesothelioma may be the nuclear deubiquitinase enzyme BAP1, which plays an important role in transcriptional deregulation in the pathogenesis of mesothelio‐ ma. BAP1 deubiquitinase is known to target histones (proteins that package DNA in the cell nucleus) and HCF1 (a transcriptional co-factor involved in the cell cycle), which also affects the E2F and Polycomb (a group of genes that codifies a family of transcription factors) target genes. Inactivating mutations of BAP1 were found in about one quarter of mesothelioma tumour tissues tested [32, 33]. Common genetic changes, involving the loss of the tumour suppressor genes p14, p16 [34], NF-2 [35], and P53, have been associated

exposure and stricter industry standards.

or other intracellular signalling cascades" [28].

**3.2. Carbon nanotubes**

**3.3. Radiation therapy**

radiation-induced mesothelioma.

**3.4. Genetic factors**

with mesothelioma [2].

**Table 1.** Incidence of Pleural and Peritoneal Mesothelioma

### **3. Epidemiology**

### **3.1. Asbestos**

The primary risk factor for mesothelioma is asbestos exposure. Asbestos is a generic terms for a group of six naturally occurring silicate minerals classified as either serpentine or amphibole. The amphibole (rod-like) group contains five types: amosite, crocidolite, anthophyllite, tremolite, and actinolite. Serpentine (chrysotile) asbestos has a sheet or layered structure and differs from the amphibole varieties both structurally and chemically. Chrysotile, the only asbestos mineral in the serpentine group, is the main form of asbestos still mined. It is generally accepted that chrysotile asbestos is less dangerous and does less damage to the lungs than the amphiboles. Although 70% to 80% of pleural mesothelioma cases are associated with asbestos exposure, the lifetime risk of developing pleural mesothelioma among asbestos workers is thought to be 10% [11]. Furthermore, despite the lack of evidence between the relationship of asbestos exposure and peritoneal mesothelioma, one study indicates that this correlation is less significant than that between asbestos exposure and pleural mesothelioma [12].

Asbestos is still used industrially for its fire-resistance and sound-absorption properties. The association between asbestos and mesothelioma was first documented in South African miners [13]. Moreover, the Occupational Safety and Health Administration (OSHA) established that 0.2 fibres per cubic millilitre of air is the standard acceptable exposure rate for fibres longer than 5 µm [14].

Construction, boiler, and shipyard workers are at increased risk. Other sources of exposure may include a spouse or close relatives of asbestos workers. Patients from certain regions of the world (i.e. Greece, Central Turkey, California, and Bulgaria) also have endogenous environmental asbestos exposure as their soil contains high level of tremolite asbestos fibres [15–19]. Furthermore, greater environmental exposure increases incidence of mesothelioma and is also proportionate to the latency period [20–21].

In the majority of patients, the disease develops after a latency period of up to 40 years after initial exposure [22]. Fortunately, today's strict industry standards have significantly reduced asbestos exposure by 100 to 1,000 times compared to the past [23]. For example, Great Britain recorded fewer annual deaths related to mesothelioma in 1968 [153] than in 2001 [1,84,8], largely due to the latency period. The peak in mesothelioma deaths is expected to occur in 2015 (2,450 deaths) [24]. Nevertheless, the rate of deaths in Great Britain associated with mesothe‐ lioma is expected to drop significantly after 2015, most likely because of reduced asbestos exposure and stricter industry standards.

Although it was once thought that smoking could lead to mesothelioma, we now know that is not the case. It does, however, increase the risk associated with asbestos exposure [25].

### **3.2. Carbon nanotubes**

**Type of Mesothelioma: Pleural Peritoneal**

Rate per 100,000 people per year: 1.98 0.41 0.15 0.09

The primary risk factor for mesothelioma is asbestos exposure. Asbestos is a generic terms for a group of six naturally occurring silicate minerals classified as either serpentine or amphibole. The amphibole (rod-like) group contains five types: amosite, crocidolite, anthophyllite, tremolite, and actinolite. Serpentine (chrysotile) asbestos has a sheet or layered structure and differs from the amphibole varieties both structurally and chemically. Chrysotile, the only asbestos mineral in the serpentine group, is the main form of asbestos still mined. It is generally accepted that chrysotile asbestos is less dangerous and does less damage to the lungs than the amphiboles. Although 70% to 80% of pleural mesothelioma cases are associated with asbestos exposure, the lifetime risk of developing pleural mesothelioma among asbestos workers is thought to be 10% [11]. Furthermore, despite the lack of evidence between the relationship of asbestos exposure and peritoneal mesothelioma, one study indicates that this correlation is

less significant than that between asbestos exposure and pleural mesothelioma [12].

and is also proportionate to the latency period [20–21].

Asbestos is still used industrially for its fire-resistance and sound-absorption properties. The association between asbestos and mesothelioma was first documented in South African miners [13]. Moreover, the Occupational Safety and Health Administration (OSHA) established that 0.2 fibres per cubic millilitre of air is the standard acceptable exposure rate for fibres longer

Construction, boiler, and shipyard workers are at increased risk. Other sources of exposure may include a spouse or close relatives of asbestos workers. Patients from certain regions of the world (i.e. Greece, Central Turkey, California, and Bulgaria) also have endogenous environmental asbestos exposure as their soil contains high level of tremolite asbestos fibres [15–19]. Furthermore, greater environmental exposure increases incidence of mesothelioma

In the majority of patients, the disease develops after a latency period of up to 40 years after initial exposure [22]. Fortunately, today's strict industry standards have significantly reduced asbestos exposure by 100 to 1,000 times compared to the past [23]. For example, Great Britain recorded fewer annual deaths related to mesothelioma in 1968 [153] than in 2001 [1,84,8], largely due to the latency period. The peak in mesothelioma deaths is expected to occur in 2015

**Table 1.** Incidence of Pleural and Peritoneal Mesothelioma

178 Cancer Treatment - Conventional and Innovative Approaches

**3. Epidemiology**

**3.1. Asbestos**

than 5 µm [14].

Gender: Men Women Men Women

Reported Cases: 1,210 320 98 72

Carbon nanotubes are stronger than steel yet lighter than aluminum. As a result, they can be found in a wide range of items such as high-performance bicycle frames, textiles (i.e. water‐ proofing fabrics), body armour, and concrete. Nevertheless, animal studies have demonstrated that carbon nanotubes can produce mesothelioma-like changes and may therefore cause mesothelioma [26,27]. Furthermore, it has been suggested that the mechanism involved may be either attributed to "changes in gene expression, epigenetic changes, and receptor-mediated or other intracellular signalling cascades" [28].

### **3.3. Radiation therapy**

Ionizing radiation to supradiaphragmatic fields appears to be a risk factor for developing mesothelioma. Data from patients treated with radiation therapy for Hodgkin's lymphoma [29], non-Hodgkin's lymphoma [30], and testicular cancer [31] revealed an excess rate of mesothelioma. Although the reported number of mesotheliomas was small, the risks were statistically significant. This might be the result of broader radiation therapy for Hodgkin's and non-Hodgkin's lymphoma, since mantle-field radiation had once been the standard method of treatment. Afterwards, extended-field radiation therapy became the standard of care. Since today's preferred method of radiation therapy for lymphomas is involved-field radiation, the incidence of mesotheliomas in patients with Hodgkin's or non-Hodgkin's lymphomas should drop because the smaller radiation-therapy fields should result in fewer secondary neoplasms. Moreover, since mediastinal radiation therapy is no longer given for testicular seminomatous germ-cell tumours, such patients should evidence a decrease in radiation-induced mesothelioma.

### **3.4. Genetic factors**

Another cause for mesothelioma may be the nuclear deubiquitinase enzyme BAP1, which plays an important role in transcriptional deregulation in the pathogenesis of mesothelio‐ ma. BAP1 deubiquitinase is known to target histones (proteins that package DNA in the cell nucleus) and HCF1 (a transcriptional co-factor involved in the cell cycle), which also affects the E2F and Polycomb (a group of genes that codifies a family of transcription factors) target genes. Inactivating mutations of BAP1 were found in about one quarter of mesothelioma tumour tissues tested [32, 33]. Common genetic changes, involving the loss of the tumour suppressor genes p14, p16 [34], NF-2 [35], and P53, have been associated with mesothelioma [2].

### **3.5. Viral oncogenes**

Simian virus 40 (SV4 0) continues to raise controversy, as it has been suggested that SV40 may have been a contaminant in the poliomyelitis vaccine in the 1950s and 1960s. A review of mesothelioma case studies have revealed an important presence of SV40 nucleic acid in affected patients. SV40 is a DNA polyomavirus, which is thought to suppress tumour genes of the retinoblastoma family by a peptide known as SV40 large T antigen [36–40].

Mesothelioma spreads by direct extension [46] and seeding throughout the pleural space, including fissures, diaphragmatic, and pericardial surfaces; through the chest wall; and into the mediastinum and lymph nodes. The malignancy may also extend into the abdominal cavity. Metastasis, although uncommon, may occur in the opposite lung, brain, and other

Mesothelioma: An Evidence-Based Review http://dx.doi.org/10.5772/55292 181

The performance status should be evaluated. Visual inspection may reveal thorax nodules or ulcers and scoliosis may be observed towards the side of the malignancy [47]. The clinician should look at all sites of previous instrumentation for evidence of tumour seeding. Unilateral dullness to percussion at the lung base may be observed. Decreased air entry on the involved

Tests should include a CBC, electrolytes, creatinine, and a complete metabolic panel. Serum soluble mesothelin-related peptide and osteopontin levels could be performed, although most

Mesothelin is a glycoprotein usually expressed on normal mesothelial cells but is overex‐ pressed in epithelioid and mixed mesotheliomas [48, 49]. A meta-analysis showed that sensitivity ranged from 19% to 68%, depending on the criteria chosen to establish positiv‐ ity [50]. The glycoprotein osteopontin is also overexpressed in mesothelioma, but a study pointed to lower diagnostic accuracy than mesothelin in patients with suspected malig‐

Thoracic, abdominal, and pelvic CT scans with contrast are useful in staging the disease. Pleural thickening is the most common finding on CT scans (92% of mesothelioma patients). Pleural thickening is defined as either extension of more than 8 cm in the craniocaudal direction or more than 5 cm of the chest wall when visualized in cross section, or when the pleural

The second most common finding is involvement of the fissure (about 85% of cases), followed by pleural effusion (75% of patients). Other findings include contraction of a hemithorax, contralateral shift of the mediastinum, chest-wall involvement, and rib destruction [55–58]. As

extrathoracic sites.

**7. Physical exam**

side may also be perceived.

nant mesothelioma [51].

thickness exceeds 3 mm [52–54].

**9. Imaging**

**9.1. CT scan**

Canadian centres do not currently do so.

**8. Lab work**

### **4. Pathology**

The histopathologic subtypes of mesothelioma are epithelioid (40%), mixed or biphasic (35%), and sarcomatous or mesenchymal (25%). Needle biopsy mesothelioma can often be mistaken for adenocarcinoma. Mesothelioma under electron microscopy reveals cells with long micro‐ villi with a needle-like shape and form. Mesothelioma is positive for calretinin, vimentin, WT1, and cytokeratin, but negative for periodic acid-shift stain, mucicarmine stain, carcinoem‐ bryonic antigen, and Leu-M1. Adenocarcinoma under electron microscopy reveals short microvilli [41].

### **5. Pathogenesis**

Inhaled asbestos fibres create lung irritation that may lead to scarring, fibrosis, and plaques. On a cellular level, injuries caused by asbestos fibres can be followed by cell repair. Repeated cell injuries, however, may lead to DNA-strand impairment and transform into malignancy [42]. It has also been suggested that long, thin asbestos fibres are generally more carcinogenic than shorter, thicker ones and interfere more with mitosis, causing chromosome abnormalities leading to cell transformation and neoplastic progression [43]. Mesothelial cells may have increased interleukin-6 secretion, which would result in increased production of vascular endothelial growth factor (VEGF), a signal protein produced by tumour cells that stimulates angiogenesis [44].

### **6. Clinical presentation**

Dyspnea and non-pleuritic chest pain are the most common presenting symptoms of meso‐ thelioma. X-rays often reveal recurrent pleural effusion or pleural thickening, which should prompt the clinician to suspect mesothelioma [45].

Early malignant pleural mesothelioma presents as small pleural nodules. As the tumour progresses, the nodules increase in number and coalesce to form a thickened tumour. As the tumour replaces the pleural fluid that lies between the two pleura, the parietal and visceral pleura fuse. This results in dyspnea and hypoxemia, which are often refractory to supplemen‐ tal oxygen when deoxygenated blood is shunted through the encased lung.

Mesothelioma spreads by direct extension [46] and seeding throughout the pleural space, including fissures, diaphragmatic, and pericardial surfaces; through the chest wall; and into the mediastinum and lymph nodes. The malignancy may also extend into the abdominal cavity. Metastasis, although uncommon, may occur in the opposite lung, brain, and other extrathoracic sites.

### **7. Physical exam**

**3.5. Viral oncogenes**

180 Cancer Treatment - Conventional and Innovative Approaches

**4. Pathology**

microvilli [41].

**5. Pathogenesis**

angiogenesis [44].

**6. Clinical presentation**

prompt the clinician to suspect mesothelioma [45].

Simian virus 40 (SV4 0) continues to raise controversy, as it has been suggested that SV40 may have been a contaminant in the poliomyelitis vaccine in the 1950s and 1960s. A review of mesothelioma case studies have revealed an important presence of SV40 nucleic acid in affected patients. SV40 is a DNA polyomavirus, which is thought to suppress tumour genes

The histopathologic subtypes of mesothelioma are epithelioid (40%), mixed or biphasic (35%), and sarcomatous or mesenchymal (25%). Needle biopsy mesothelioma can often be mistaken for adenocarcinoma. Mesothelioma under electron microscopy reveals cells with long micro‐ villi with a needle-like shape and form. Mesothelioma is positive for calretinin, vimentin, WT1, and cytokeratin, but negative for periodic acid-shift stain, mucicarmine stain, carcinoem‐ bryonic antigen, and Leu-M1. Adenocarcinoma under electron microscopy reveals short

Inhaled asbestos fibres create lung irritation that may lead to scarring, fibrosis, and plaques. On a cellular level, injuries caused by asbestos fibres can be followed by cell repair. Repeated cell injuries, however, may lead to DNA-strand impairment and transform into malignancy [42]. It has also been suggested that long, thin asbestos fibres are generally more carcinogenic than shorter, thicker ones and interfere more with mitosis, causing chromosome abnormalities leading to cell transformation and neoplastic progression [43]. Mesothelial cells may have increased interleukin-6 secretion, which would result in increased production of vascular endothelial growth factor (VEGF), a signal protein produced by tumour cells that stimulates

Dyspnea and non-pleuritic chest pain are the most common presenting symptoms of meso‐ thelioma. X-rays often reveal recurrent pleural effusion or pleural thickening, which should

Early malignant pleural mesothelioma presents as small pleural nodules. As the tumour progresses, the nodules increase in number and coalesce to form a thickened tumour. As the tumour replaces the pleural fluid that lies between the two pleura, the parietal and visceral pleura fuse. This results in dyspnea and hypoxemia, which are often refractory to supplemen‐

tal oxygen when deoxygenated blood is shunted through the encased lung.

of the retinoblastoma family by a peptide known as SV40 large T antigen [36–40].

The performance status should be evaluated. Visual inspection may reveal thorax nodules or ulcers and scoliosis may be observed towards the side of the malignancy [47]. The clinician should look at all sites of previous instrumentation for evidence of tumour seeding. Unilateral dullness to percussion at the lung base may be observed. Decreased air entry on the involved side may also be perceived.

### **8. Lab work**

Tests should include a CBC, electrolytes, creatinine, and a complete metabolic panel. Serum soluble mesothelin-related peptide and osteopontin levels could be performed, although most Canadian centres do not currently do so.

Mesothelin is a glycoprotein usually expressed on normal mesothelial cells but is overex‐ pressed in epithelioid and mixed mesotheliomas [48, 49]. A meta-analysis showed that sensitivity ranged from 19% to 68%, depending on the criteria chosen to establish positiv‐ ity [50]. The glycoprotein osteopontin is also overexpressed in mesothelioma, but a study pointed to lower diagnostic accuracy than mesothelin in patients with suspected malig‐ nant mesothelioma [51].

### **9. Imaging**

### **9.1. CT scan**

Thoracic, abdominal, and pelvic CT scans with contrast are useful in staging the disease. Pleural thickening is the most common finding on CT scans (92% of mesothelioma patients). Pleural thickening is defined as either extension of more than 8 cm in the craniocaudal direction or more than 5 cm of the chest wall when visualized in cross section, or when the pleural thickness exceeds 3 mm [52–54].

The second most common finding is involvement of the fissure (about 85% of cases), followed by pleural effusion (75% of patients). Other findings include contraction of a hemithorax, contralateral shift of the mediastinum, chest-wall involvement, and rib destruction [55–58]. As the disease progresses, irregular pleura-based masses are common and the interlobular fissures are often involved. CT scanning may underestimate the extent of disease.

T1a: No involvement of the visceral pleura T1b: Tumour also involving the visceral pleura

destruction

Nx: Regional lymph nodes cannot be assessed N0: No regional lymph-node metastases

and peridiaphragmatic nodes)

Mx: Distant metastasis cannot be assessed

**Regional Lymph Nodes (N)**

**Distant Metastasis (M)**

**Stage Groups** I T1N0M0 IA T1aN0M0

M0: No distant metastasis M1: Distant metastasis

pleura) with at least one of the following:

(1) Involvement of diaphragmatic muscle

(1) Involvement of the endothoracic fascia (2) Extension into the mediastinal fat

4) Nontransmural involvement of the pericardium

T2: Tumour involves each of the ipsilateral pleural surfaces (parietal, mediastinal, diaphragmatic, and visceral

(2) Extension of tumour from visceral pleura into underlying pulmonary parenchyma T3: Locally advanced but potentially resectable tumour. Tumour involving all of the ipsilateral pleural surfaces (parietal, mediastinal, diaphragmatic, and visceral pleura) with at least one of the following:

T4: Locally advanced, technically unresectable tumour. Tumour involving all of the ipsilateral pleural surfaces (parietal, mediastinal, diaphragmatic, and visceral pleura) with at least one of the following:

N2: Metastases in the subcarinal or ipsilateral mediastinal lymph node (including ipsilateral internal mammary

N3: Metastases in the contralateral mediastinal, internal, mammary, or hilar nodes and/or the ipsilateral or

(2)Direct diaphragmatic extension of the tumour to the peritoneum

(3)Direct extension of the tumour to a mediastinal organ (4)Direct extension of the tumour to the contralateral pleura

(5)Direct extension of the tumour into the spine

effusion or tumour involving the myocardium

N1: Metastases in the ipsilateral bronchopulmonary and/or hilar lymph nodes

contralateral supraclavicular or scalene lymph nodes

(3) Solitary completely resectable focus of tumour extending into the soft tissue of the chest wall

Mesothelioma: An Evidence-Based Review http://dx.doi.org/10.5772/55292 183

(1) Diffuse extension or multifocal masses of tumour in the chest wall, with or without associated rib

(6)Tumour extending through to the internal surface of the pericardium with or without a pericardial

Although CT scanning is used for tumour detection, its accuracy for detecting intrathoracic lymph-node involvement is limited [59, 60]. Mesothelioma spreads into paraesophageal nodes, pulmonary-ligament nodes, and diaphragmatic nodes more commonly than other lung cancers.

#### **9.2. MRI**

Combining magnetic resonance imaging (MRI) with CT scanning may improve evaluation of the local extent of disease. MRI helps to determine chest-wall, diaphragmatic, or apical invasion as well as transdiaphragmatic tumour growth [57].

#### **9.3. PET–CT scan**

PET–CT scanning may be useful in detecting mediastinal lymph-node involvement or extrathoracic diseases and to reclassify patients as inoperable [61–65].

### **10. Surgical staging**

Although radiographic staging evaluation is warranted, accurate staging is only possible at the time of surgery in a substantial number of patients. Pulmonary-function tests are often performed prior to surgery. For surgical staging, mediastinoscopy or endobronchial ultra‐ sound is used in the case of suspicious nodes. An open biopsy or CT-guided core biopsy is acceptable, but thoracenthesis or video-assisted thorascopic surgery (VATS) is preferred. If necessary, based on the CT scan, laparoscopy can be used to rule out transdiaphragmatic extension, and VATS to rule out contralateral disease.

### **11. TNM staging of mesothelioma**

The TNM (Tumour, Node, Metastasis) Classification is used by both the Union for Interna‐ tional Cancer Control (UICC) and the American Joint Committee on Cancer (AJCC). The 2010 version is the most recent.

#### **Primary Tumour (T)**


T1a: No involvement of the visceral pleura

the disease progresses, irregular pleura-based masses are common and the interlobular

Although CT scanning is used for tumour detection, its accuracy for detecting intrathoracic lymph-node involvement is limited [59, 60]. Mesothelioma spreads into paraesophageal nodes, pulmonary-ligament nodes, and diaphragmatic nodes more commonly than other lung

Combining magnetic resonance imaging (MRI) with CT scanning may improve evaluation of the local extent of disease. MRI helps to determine chest-wall, diaphragmatic, or apical

PET–CT scanning may be useful in detecting mediastinal lymph-node involvement or

Although radiographic staging evaluation is warranted, accurate staging is only possible at the time of surgery in a substantial number of patients. Pulmonary-function tests are often performed prior to surgery. For surgical staging, mediastinoscopy or endobronchial ultra‐ sound is used in the case of suspicious nodes. An open biopsy or CT-guided core biopsy is acceptable, but thoracenthesis or video-assisted thorascopic surgery (VATS) is preferred. If necessary, based on the CT scan, laparoscopy can be used to rule out transdiaphragmatic

The TNM (Tumour, Node, Metastasis) Classification is used by both the Union for Interna‐ tional Cancer Control (UICC) and the American Joint Committee on Cancer (AJCC). The 2010

T1: Tumour limited to the ipsilateral parietal pleura, with or without mediastinal pleura and with or without

fissures are often involved. CT scanning may underestimate the extent of disease.

invasion as well as transdiaphragmatic tumour growth [57].

182 Cancer Treatment - Conventional and Innovative Approaches

extension, and VATS to rule out contralateral disease.

**11. TNM staging of mesothelioma**

extrathoracic diseases and to reclassify patients as inoperable [61–65].

cancers.

**9.2. MRI**

**9.3. PET–CT scan**

**10. Surgical staging**

version is the most recent.

Tx: Primary tumour cannot be assessed T0: No evidence of primary tumour

diaphragmatic pleural involvement

**Primary Tumour (T)**

	- (1) Involvement of diaphragmatic muscle
	- (2) Extension of tumour from visceral pleura into underlying pulmonary parenchyma
	- (1) Involvement of the endothoracic fascia
	- (2) Extension into the mediastinal fat
	- (3) Solitary completely resectable focus of tumour extending into the soft tissue of the chest wall
	- 4) Nontransmural involvement of the pericardium
	- (1) Diffuse extension or multifocal masses of tumour in the chest wall, with or without associated rib destruction
	- (2)Direct diaphragmatic extension of the tumour to the peritoneum
	- (3)Direct extension of the tumour to a mediastinal organ
	- (4)Direct extension of the tumour to the contralateral pleura
	- (5)Direct extension of the tumour into the spine
	- (6)Tumour extending through to the internal surface of the pericardium with or without a pericardial effusion or tumour involving the myocardium

#### **Regional Lymph Nodes (N)**


#### **Distant Metastasis (M)**


#### **Stage Groups**


### **12. Differential diagnosis**

Even though most pleural tumours are malignant, the differential diagnosis also includes benign tumours and inflammatory reactions.

Neoadjuvant chemotherapy, then EPP followed by hemithorax radiation therapy [72–73]

A combination of chemotherapy is the standard treatment. Prophylactic drain-site irradiation

Mesothelioma: An Evidence-Based Review http://dx.doi.org/10.5772/55292 185

Talc pleurodesis with a pleural catheter or pleurectomy may also be considered to palliate

EPP involves the removal of parietal pleura, lung, pericardium, and ipsilateral diaphragm. Mediastinal node dissection is usually performed. Finally, a graft is inserted to prevent herniation of abdominal contents through the diaphragmatic defect. Although no survival benefit was observed from randomized trials, observational studies indicated that EPP is the only intervention that has been demonstrated to result in long-term, disease-free survival in highly selected patients with favourable prognostic indication [7]. In a review of 83 patients

The benefits of EPP is that it allows complete resection or at least a cytoreduction, permitting higher radiation doses to be delivered safely to the ipsilateral hemithorax. This procedure has the disadvantage of being technically complex and associated with signifi‐ cant perioperative morbidity and mortality. Complications include atrial fibrillation (44.2%), prolonged intubation (7.9%), vocal-cord paralysis (6.7%), deep-vein thrombosis (6.4%), technical complications (patch dehiscence, haemorrhage, or both; 6.1%), tamponade (3.6%), acute respiratory-distress syndrome (3.6%), cardiac arrest (3%), constrictive physiology (2.7%), aspiration (2.7%), renal failure (2.7%), empyema (2.4%), tracheostomy 1.8%, myocardial infarction (1.5%), pulmonary embolus (1.5%), and bronchopleural fistula (0.6%) [75]. In extensive experience, the early postoperative mortality rate approaches 7% [76] but can be as high as 30%. The mean survival (MS) rate after surgery is 4 to 20 months.

Prior to surgery, it is important to have proper patient selection. Patients must have:

If the tumour is unresectable:

symptoms of pleural effusion.

Performance status of 0–1

An epithelioid histology

PaO2 of more than 65 mm Hg PaCO2 of less than 45 mm Hg

A predicted post op FEV1 of more than 1 L

**14.1. Extrapleural Pneumonectomy (EPP)**

A mean pulmonary arterial pressure of less than 30 mm Hg

who underwent EPP, the observed 5-year survival rate was 15% [74].

An ejection fraction of more than 40%

should be considered.

**14. Surgery**

Primary tumours, such as fibrosarcoma and malignant fibrous histiocytoma, can present in a similar fashion and infiltrate like sarcomatous mesotheliomas. Metastatic diseases that can involve the pleura and mimic epithelioid mesothelioma include breast, lung, lymphoma, thymoma, stomach, kidney, ovarian, and prostate cancer. Finally, benign chronic organized empyema can also mimic pleural thickening.

### **13. Treatments**

The median survival of patients with mesothelioma is poor, ranging from 7 to 17 months [66]. The overall survival (OS) rate at 5 years is 9%. Even with new therapy interventions, the overall patient survival rate has not been significantly improved. In some specific cases, in which patients were specifically chosen due to their localized disease, treatment with aggressive multimodality therapy improved their survival rates.

The first thing to consider when treating mesothelioma is whether the tumour is resectable or not. Since the tumour spreads by direct extension, only 5% of mesotheliomas are resectable at diagnosis. Usually T1 to T3 and N0-1 tumours are considered resectable. T4 and N2-3 tumours are considered unresectable. Mediastinoscopy has to be performed to rule out N2-N3 lymph nodes. In addition, patients with sarcomatoid histology have a poorer prognosis and should not be considered for extrapleural pneumonectomy [67]. Patients must be able to tolerate trimodal therapy, since it is important to ensure that they do not have postoperative morbid‐ ities without deriving the full benefits of surgery.

The treatment paradigms for resectable mesothelioma are:

Extrapleural pneumonectomy (EPP), then chemotherapy followed by hemithorax radiation therapy [7, 68–71]

Neoadjuvant chemotherapy, then EPP followed by hemithorax radiation therapy [72–73]

If the tumour is unresectable:

A combination of chemotherapy is the standard treatment. Prophylactic drain-site irradiation should be considered.

Talc pleurodesis with a pleural catheter or pleurectomy may also be considered to palliate symptoms of pleural effusion.

### **14. Surgery**

IB T1bN0M0 II T2N0M0 III T1-2N1M0

T1-2N2M0 T3N0-2M0 IV T4 and any NMO

Any T and N3M0

Any T and any N and M1

184 Cancer Treatment - Conventional and Innovative Approaches

**12. Differential diagnosis**

**13. Treatments**

therapy [7, 68–71]

benign tumours and inflammatory reactions.

empyema can also mimic pleural thickening.

multimodality therapy improved their survival rates.

ities without deriving the full benefits of surgery.

The treatment paradigms for resectable mesothelioma are:

Even though most pleural tumours are malignant, the differential diagnosis also includes

Primary tumours, such as fibrosarcoma and malignant fibrous histiocytoma, can present in a similar fashion and infiltrate like sarcomatous mesotheliomas. Metastatic diseases that can involve the pleura and mimic epithelioid mesothelioma include breast, lung, lymphoma, thymoma, stomach, kidney, ovarian, and prostate cancer. Finally, benign chronic organized

The median survival of patients with mesothelioma is poor, ranging from 7 to 17 months [66]. The overall survival (OS) rate at 5 years is 9%. Even with new therapy interventions, the overall patient survival rate has not been significantly improved. In some specific cases, in which patients were specifically chosen due to their localized disease, treatment with aggressive

The first thing to consider when treating mesothelioma is whether the tumour is resectable or not. Since the tumour spreads by direct extension, only 5% of mesotheliomas are resectable at diagnosis. Usually T1 to T3 and N0-1 tumours are considered resectable. T4 and N2-3 tumours are considered unresectable. Mediastinoscopy has to be performed to rule out N2-N3 lymph nodes. In addition, patients with sarcomatoid histology have a poorer prognosis and should not be considered for extrapleural pneumonectomy [67]. Patients must be able to tolerate trimodal therapy, since it is important to ensure that they do not have postoperative morbid‐

Extrapleural pneumonectomy (EPP), then chemotherapy followed by hemithorax radiation

Prior to surgery, it is important to have proper patient selection. Patients must have:

Performance status of 0–1

PaO2 of more than 65 mm Hg

PaCO2 of less than 45 mm Hg

A predicted post op FEV1 of more than 1 L

An ejection fraction of more than 40%

A mean pulmonary arterial pressure of less than 30 mm Hg

An epithelioid histology

#### **14.1. Extrapleural Pneumonectomy (EPP)**

EPP involves the removal of parietal pleura, lung, pericardium, and ipsilateral diaphragm. Mediastinal node dissection is usually performed. Finally, a graft is inserted to prevent herniation of abdominal contents through the diaphragmatic defect. Although no survival benefit was observed from randomized trials, observational studies indicated that EPP is the only intervention that has been demonstrated to result in long-term, disease-free survival in highly selected patients with favourable prognostic indication [7]. In a review of 83 patients who underwent EPP, the observed 5-year survival rate was 15% [74].

The benefits of EPP is that it allows complete resection or at least a cytoreduction, permitting higher radiation doses to be delivered safely to the ipsilateral hemithorax. This procedure has the disadvantage of being technically complex and associated with signifi‐ cant perioperative morbidity and mortality. Complications include atrial fibrillation (44.2%), prolonged intubation (7.9%), vocal-cord paralysis (6.7%), deep-vein thrombosis (6.4%), technical complications (patch dehiscence, haemorrhage, or both; 6.1%), tamponade (3.6%), acute respiratory-distress syndrome (3.6%), cardiac arrest (3%), constrictive physiology (2.7%), aspiration (2.7%), renal failure (2.7%), empyema (2.4%), tracheostomy 1.8%, myocardial infarction (1.5%), pulmonary embolus (1.5%), and bronchopleural fistula (0.6%) [75]. In extensive experience, the early postoperative mortality rate approaches 7% [76] but can be as high as 30%. The mean survival (MS) rate after surgery is 4 to 20 months.

### **14.2. Pleurectomy/Decortication (P/D)**

In case of more advanced disease, mixed histology, and medically high-risk operable patients, pleurectomy/decortication is preferred over EPP. Pleurectomy/decortication is performed in two phases. Phase 1 is pleurectomy and involves removing the pleural lining. Phase 2 is decortication, which is the removal of any tumour growing inside the lining. The procedure's perioperative mortality is 4% [76].

IMRT can be delivered according to the method published by the MDACC experiment using 13 to 27 fields with 8 to 11 gantry angles with 100 segments/fields. The target volume was the entire hemithorax, all surgical clips, all sites of instrumentation, and the ipsilateral mediasti‐ num with an initial dose to 45-50 Gy, with a boost to 60 Gy for a close/positive margin. The two-year survival rate was 62% and the three-year disease-free survival (DFS) rate was 45% for negative lymph nodes and epithelioid histology. Five patients with stage-I disease had a three-year DFS of 100%. IMRT has the potential to decrease pulmonary toxicity if correct

Mesothelioma: An Evidence-Based Review http://dx.doi.org/10.5772/55292 187

In order to decrease the side effects of radiation therapy, several dose-volume restrictions are applied. The V20 (the volume receiving 20 Gy or more) of the lung must not exceed 7%, since Rice DC et al. [86] showed a relative risk of 42% for fatal pneumonitis. The oesophagus V55 should be less than 30%; the liver V30 should be less than 30%. The kidneys V15 should be less than 20%; the heart V40 less than 50%; the spinal cord V45 less than 10%; no volume should

A debate in radiation oncology for mesothelioma remains whether to offer radiation therapy to inoperable patients following an invasive procedure or following a biopsy in order to avoid needle-tract seeding from the tumour. The incidence of tumour seeding along the biopsy tract may range from 0% to 43% and may lead to the formation of painful subcutaneous lesions [87]. Three randomized trials [88–90] evaluated RT following thoracoscopy or thoracotomy to prevent tumour seeding. The radiation-therapy regimen was generally 3 fractions of 7 Gy (total of 21 Gy). O'Rouke et al. showed, in their randomized trial with 61 patients, that prophylactic radiation therapy to drain sites did not statistically reduce the rate of seeding. Boutin's study (40 patients) revealed a clear benefit of radiation at the biopsy site with reduction of biopsy-tract metastasis from 40% to 0% (p < 0.00 1). At the Hôtel-Dieu de Québec Hospital, however, Marie-Anne Froment et al. [91] reported a benefit of radiation therapy to avoid needle-tract seeding from the tumour. At 6 months, local progression-free survival for the intervention sites was 91% with prophylactic radiation therapy and 74% without irradiation (p = 0.00 2). During follow-up, 6 patients (13%) in the treated group had tumour invasion of the subcutane‐ ous tissue compared to 40 patients (33%) in the group without radiation (p = 0.00 8). Because recurrence is morbid and this treatment is easily feasible, Hôtel-Dieu de Québec

The side effects of radiation therapy can be classified according to time of occurrence: acute, intermediate, or late. Acute effects, if they appear, are expected to start during treatment and be resolved within 3 months following treatment. Potential acute side effects are fatigue, skin reactions, nausea, vomiting, dysphagia, odynophagia, and cough. Potential intermediate side effects include pneumonitis and Hermitte's syndrome. If intermediate side effects occur, they usually do so 3 months after treatment and resolve within 6 months.

treatment algorithms are applied.

**15.2. Radiation therapy to the biopsy site**

Hospital generally offers radiation therapy to such patients.

**15.3. Side effects of radiation therapy after EPP**

be more than 50 Gy.

Retrospective studies have indicated that parietal pleurectomy and decortication may be as efficient as extrapleural pneumonectomy [76]. When comparing EPP to PD, it was observed that PD patients had a greater local recurrence of disease, while EPP patients experienced higher mortality and surgical morbidity.

### **15. Radiotherapy (RT)**

#### **15.1. Adjuvant radiation therapy after EPP**

Radiation therapy is a local treatment that uses ionizing radiation to destroy tumour cells. As mentioned above, aggressive surgery alone does not improve survival. Observational data do not provide evidence that adjuvant RT following pleurectomy offers a survival benefit [77]. That notwithstanding, the MSKCC phase-II trial with hemithorax radiotherapy to 54 Gy following EPP showed improved mean survival rates at 34 months for stage I-II disease and at 10 months with later-stage disease compared to historical controls [78]. In addition to a small survival benefit demonstrated in the MSKCC study, the rationale for using radiation therapy is local control. The disease is of a diffuse nature and manipulating the exposed tumour during EPP puts the entire ipsilateral chest wall, diaphragm insertion, pericardium, mediastinum, and bronchial stump at a very high risk of local recurrence, as high as 80% of patients, as reported in [78]. The evaluation of high-dose radiation therapy showed that the use of adjuvant radiation decreased the risk of local recurrence to 13% [78].

Mesothelioma is considered a tumour sensitive to external-beam radiation therapy. The recommended postoperative doses are 50 Gy for negative surgical margins, 54 to 60 Gy for close or positive margins, and 60 Gy for gross tumours [79–83]. The radiation dose has to be limited, however, due to the treatment required to the entire hemithorax and the sensitivity of critical organs such as the heart, lungs, oesophagus, liver, kidneys, and spinal cord to radiation [68].

Treatment volumes include ipsilateral mediastinum even for node-negative tumours. The superior border should include the thoracic inlet. The medial border should include the trachea, subcarinal lymph nodes, and the vertebral body. The inferior border is the insertion of the diaphragm, ranging from L1 to L4. Radiation oncologists should be careful to include the anteromedial pleural reflection of the sternopericardial recess, the medial and inferior extent of the crus of the diaphragm, and the inferior insertion of the diaphragm in the treatment volume. Nowadays, radiation therapy is delivered using three-dimensional conformal radiation therapy (3DCRT) or intensity-modulated radiation therapy (IMRT) [70, 71, 84, 85]. IMRT can be delivered according to the method published by the MDACC experiment using 13 to 27 fields with 8 to 11 gantry angles with 100 segments/fields. The target volume was the entire hemithorax, all surgical clips, all sites of instrumentation, and the ipsilateral mediasti‐ num with an initial dose to 45-50 Gy, with a boost to 60 Gy for a close/positive margin. The two-year survival rate was 62% and the three-year disease-free survival (DFS) rate was 45% for negative lymph nodes and epithelioid histology. Five patients with stage-I disease had a three-year DFS of 100%. IMRT has the potential to decrease pulmonary toxicity if correct treatment algorithms are applied.

In order to decrease the side effects of radiation therapy, several dose-volume restrictions are applied. The V20 (the volume receiving 20 Gy or more) of the lung must not exceed 7%, since Rice DC et al. [86] showed a relative risk of 42% for fatal pneumonitis. The oesophagus V55 should be less than 30%; the liver V30 should be less than 30%. The kidneys V15 should be less than 20%; the heart V40 less than 50%; the spinal cord V45 less than 10%; no volume should be more than 50 Gy.

### **15.2. Radiation therapy to the biopsy site**

**14.2. Pleurectomy/Decortication (P/D)**

186 Cancer Treatment - Conventional and Innovative Approaches

perioperative mortality is 4% [76].

**15. Radiotherapy (RT)**

radiation [68].

higher mortality and surgical morbidity.

**15.1. Adjuvant radiation therapy after EPP**

radiation decreased the risk of local recurrence to 13% [78].

In case of more advanced disease, mixed histology, and medically high-risk operable patients, pleurectomy/decortication is preferred over EPP. Pleurectomy/decortication is performed in two phases. Phase 1 is pleurectomy and involves removing the pleural lining. Phase 2 is decortication, which is the removal of any tumour growing inside the lining. The procedure's

Retrospective studies have indicated that parietal pleurectomy and decortication may be as efficient as extrapleural pneumonectomy [76]. When comparing EPP to PD, it was observed that PD patients had a greater local recurrence of disease, while EPP patients experienced

Radiation therapy is a local treatment that uses ionizing radiation to destroy tumour cells. As mentioned above, aggressive surgery alone does not improve survival. Observational data do not provide evidence that adjuvant RT following pleurectomy offers a survival benefit [77]. That notwithstanding, the MSKCC phase-II trial with hemithorax radiotherapy to 54 Gy following EPP showed improved mean survival rates at 34 months for stage I-II disease and at 10 months with later-stage disease compared to historical controls [78]. In addition to a small survival benefit demonstrated in the MSKCC study, the rationale for using radiation therapy is local control. The disease is of a diffuse nature and manipulating the exposed tumour during EPP puts the entire ipsilateral chest wall, diaphragm insertion, pericardium, mediastinum, and bronchial stump at a very high risk of local recurrence, as high as 80% of patients, as reported in [78]. The evaluation of high-dose radiation therapy showed that the use of adjuvant

Mesothelioma is considered a tumour sensitive to external-beam radiation therapy. The recommended postoperative doses are 50 Gy for negative surgical margins, 54 to 60 Gy for close or positive margins, and 60 Gy for gross tumours [79–83]. The radiation dose has to be limited, however, due to the treatment required to the entire hemithorax and the sensitivity of critical organs such as the heart, lungs, oesophagus, liver, kidneys, and spinal cord to

Treatment volumes include ipsilateral mediastinum even for node-negative tumours. The superior border should include the thoracic inlet. The medial border should include the trachea, subcarinal lymph nodes, and the vertebral body. The inferior border is the insertion of the diaphragm, ranging from L1 to L4. Radiation oncologists should be careful to include the anteromedial pleural reflection of the sternopericardial recess, the medial and inferior extent of the crus of the diaphragm, and the inferior insertion of the diaphragm in the treatment volume. Nowadays, radiation therapy is delivered using three-dimensional conformal radiation therapy (3DCRT) or intensity-modulated radiation therapy (IMRT) [70, 71, 84, 85].

A debate in radiation oncology for mesothelioma remains whether to offer radiation therapy to inoperable patients following an invasive procedure or following a biopsy in order to avoid needle-tract seeding from the tumour. The incidence of tumour seeding along the biopsy tract may range from 0% to 43% and may lead to the formation of painful subcutaneous lesions [87]. Three randomized trials [88–90] evaluated RT following thoracoscopy or thoracotomy to prevent tumour seeding. The radiation-therapy regimen was generally 3 fractions of 7 Gy (total of 21 Gy). O'Rouke et al. showed, in their randomized trial with 61 patients, that prophylactic radiation therapy to drain sites did not statistically reduce the rate of seeding. Boutin's study (40 patients) revealed a clear benefit of radiation at the biopsy site with reduction of biopsy-tract metastasis from 40% to 0% (p < 0.00 1). At the Hôtel-Dieu de Québec Hospital, however, Marie-Anne Froment et al. [91] reported a benefit of radiation therapy to avoid needle-tract seeding from the tumour. At 6 months, local progression-free survival for the intervention sites was 91% with prophylactic radiation therapy and 74% without irradiation (p = 0.00 2). During follow-up, 6 patients (13%) in the treated group had tumour invasion of the subcutane‐ ous tissue compared to 40 patients (33%) in the group without radiation (p = 0.00 8). Because recurrence is morbid and this treatment is easily feasible, Hôtel-Dieu de Québec Hospital generally offers radiation therapy to such patients.

#### **15.3. Side effects of radiation therapy after EPP**

The side effects of radiation therapy can be classified according to time of occurrence: acute, intermediate, or late. Acute effects, if they appear, are expected to start during treatment and be resolved within 3 months following treatment. Potential acute side effects are fatigue, skin reactions, nausea, vomiting, dysphagia, odynophagia, and cough. Potential intermediate side effects include pneumonitis and Hermitte's syndrome. If intermediate side effects occur, they usually do so 3 months after treatment and resolve within 6 months. Finally, potential late effects would occur 6 months following treatment and could include pulmonary fibrosis, pericarditis, restrictive cardiomyopathy, myocardial infarction, congestive heart failure, and radiation myelopathy.

first agent to receive Food and Drug Administration (FDA) approval for use in combination with cisplatin. The combination of pemetrexed and carboplatin were studied in two phase-II studies, the response rates and mean survival rates were 18.6% and 12.7 months in the Ceresoli

Mesothelioma: An Evidence-Based Review http://dx.doi.org/10.5772/55292 189

Several trials [97, 98] have evaluated the addition of gemcitabine, a cytidine analogue. Only 38% of patients received the four cycles as prescribed and the response rate was 26% among those who completed the treatment [98]. It should be noted that the study only included earlystage mesothelioma. Vinca alkaloid-containing regimen was compared to MVP (mitomycin, vinblastine, and cisplatin) in terms of symptom control. The median survival benefit was an

Pemetrexed as a single agent has been studied. In one phase-II trial [100], the study design was revised to incorporate folic acid and cynocobalamin in addition to dexamethasone. The median progression-free survival was 16.3 months in the pemetrexed/vitamin-supplemented group versus 9.5 months for the pemetrexed group. Other single agents such as gemcitabine, anthracyclines, and taxanes have been tested but resulted in low response rates, such as 10%

Cisplatin and carboplatin are platinum analogues. The potential side effects of platinum agents include dose-limiting myelosuppression, nausea, vomiting, renal impairment, hearing impairment, and peripheral neuropathy. Pemetrexed is an antifolate compound. Potential side

Recent anticancer agents focus on molecular targets such as surface receptors and cellsignalling proteins. Although it has been shown that mesothelial cells express the vascular endothelial growth factor (VEGF) receptor, a recent study [101] failed to demonstrate survival improvement with bevacizumab. Erlotinib, a tyrosine-kinase inhibitor of the epidermal growth-factor receptor (EGFR), was tested in a phase-II trial. EGFR is expressed primarily in the epithelial subtype of mesothelioma. Of the 63 patients who were enrolled, only 29 were

The European Organisation for Research and Treatment of Cancer (EORTC) reviewed data for 204 adults who were enrolled in five consecutive phase-II trials over nine years. The EORTC

effects include myelosuppression, nausea, skin rash, alopecia, diarrhoea, and fatigue.

assessed for outcomes; no objective responses were reported [102].

study [95] and 25% and 14 months in the Castagneto study [96].

additional 2 months [99].

**16.4. Single-agent chemotherapy**

**16.5. Chemotherapy side effects**

**17. Molecular target therapy**

**18. Prognosis and overall survival**

poor prognostic factors [103] for mesothelioma are:

### **16. Chemotherapy**

### **Adjuvant or Neoadjuvant Chemotherapy**

Anthracyclines have historically been the most commonly used pharmacologic agents, with reported response rates of 19% [92]. Recent trials using platinum in combination with folate analogues have improved cytotoxic activity against mesothelioma. The preferred treatment during these recent trials was a combination of chemotherapy incorporated with a trimodal regimen, as adjuvant or neoadjuvant chemotherapy options are either pemetrexed/cisplatin or gemcitabine/cisplatin.

#### **16.1. Adjuvant chemotherapy**

Patients treated with EPP, followed by radiation therapy and adjuvant chemotherapy, had a median survival rates of 36 % and 14% at two to five years, respectively. Historically, the chemotherapy used was doxorubicin, cyclophosphamide, and cisplatin for four to six cycles [93]. A Harvard retrospective [93] review of 183 patients treated with a trimodality approach using adjuvant chemotherapy of Cytoxan/Adriamycin/cisplatin (CAP) or carboplatin/Taxol with concurrent radiation therapy followed by adjuvant chemotherapy had an overall mean survival rate of 19 months and a 5-year overall survival (OS) rate of 15%.

#### **16.2. Neoadjuvant chemotherapy**

The rationale for using neoadjuvant chemotherapy prior to surgery is that it may increase tolerance and improve response to surgery. A multicenter phase-II trial [72] evaluated the role of neoadjuvant chemotherapy prior to EPP and RT. The chemotherapy consisted of four cycles of pemetrexed plus cisplatin. The median survival rate of the patients who completed the therapy was 29 months; the two-year survival rate was 61%. De Perrot et al. [73] reported a median survival rate of 59 months in a subgroup of patients who had completed trimodal therapy with neoadjuvant chemotherapy, EPP, and then RT. The median survival rate was less than 14 months for the patients who did not complete the treatment regimen.

#### **Chemotherapy as a definitive treatment**

#### **16.3. Combination chemotherapy**

Combination-chemotherapy regimens using pemetrexed and platinum-based agents have yielded superior outcomes than single agents. Volgezang NJ et al. [94] showed that, for unresectable tumours, cisplatin/pemetrexed improved the response rate of 17% vs. 40% and the MS rate from 9 to 12 months compared to cisplatin alone. In 2004, pemetrexed became the first agent to receive Food and Drug Administration (FDA) approval for use in combination with cisplatin. The combination of pemetrexed and carboplatin were studied in two phase-II studies, the response rates and mean survival rates were 18.6% and 12.7 months in the Ceresoli study [95] and 25% and 14 months in the Castagneto study [96].

Several trials [97, 98] have evaluated the addition of gemcitabine, a cytidine analogue. Only 38% of patients received the four cycles as prescribed and the response rate was 26% among those who completed the treatment [98]. It should be noted that the study only included earlystage mesothelioma. Vinca alkaloid-containing regimen was compared to MVP (mitomycin, vinblastine, and cisplatin) in terms of symptom control. The median survival benefit was an additional 2 months [99].

### **16.4. Single-agent chemotherapy**

Finally, potential late effects would occur 6 months following treatment and could include pulmonary fibrosis, pericarditis, restrictive cardiomyopathy, myocardial infarction,

Anthracyclines have historically been the most commonly used pharmacologic agents, with reported response rates of 19% [92]. Recent trials using platinum in combination with folate analogues have improved cytotoxic activity against mesothelioma. The preferred treatment during these recent trials was a combination of chemotherapy incorporated with a trimodal regimen, as adjuvant or neoadjuvant chemotherapy options are either pemetrexed/cisplatin

Patients treated with EPP, followed by radiation therapy and adjuvant chemotherapy, had a median survival rates of 36 % and 14% at two to five years, respectively. Historically, the chemotherapy used was doxorubicin, cyclophosphamide, and cisplatin for four to six cycles [93]. A Harvard retrospective [93] review of 183 patients treated with a trimodality approach using adjuvant chemotherapy of Cytoxan/Adriamycin/cisplatin (CAP) or carboplatin/Taxol with concurrent radiation therapy followed by adjuvant chemotherapy had an overall mean

The rationale for using neoadjuvant chemotherapy prior to surgery is that it may increase tolerance and improve response to surgery. A multicenter phase-II trial [72] evaluated the role of neoadjuvant chemotherapy prior to EPP and RT. The chemotherapy consisted of four cycles of pemetrexed plus cisplatin. The median survival rate of the patients who completed the therapy was 29 months; the two-year survival rate was 61%. De Perrot et al. [73] reported a median survival rate of 59 months in a subgroup of patients who had completed trimodal therapy with neoadjuvant chemotherapy, EPP, and then RT. The median survival rate was less

Combination-chemotherapy regimens using pemetrexed and platinum-based agents have yielded superior outcomes than single agents. Volgezang NJ et al. [94] showed that, for unresectable tumours, cisplatin/pemetrexed improved the response rate of 17% vs. 40% and the MS rate from 9 to 12 months compared to cisplatin alone. In 2004, pemetrexed became the

survival rate of 19 months and a 5-year overall survival (OS) rate of 15%.

than 14 months for the patients who did not complete the treatment regimen.

congestive heart failure, and radiation myelopathy.

**Adjuvant or Neoadjuvant Chemotherapy**

188 Cancer Treatment - Conventional and Innovative Approaches

**16. Chemotherapy**

or gemcitabine/cisplatin.

**16.1. Adjuvant chemotherapy**

**16.2. Neoadjuvant chemotherapy**

**Chemotherapy as a definitive treatment**

**16.3. Combination chemotherapy**

Pemetrexed as a single agent has been studied. In one phase-II trial [100], the study design was revised to incorporate folic acid and cynocobalamin in addition to dexamethasone. The median progression-free survival was 16.3 months in the pemetrexed/vitamin-supplemented group versus 9.5 months for the pemetrexed group. Other single agents such as gemcitabine, anthracyclines, and taxanes have been tested but resulted in low response rates, such as 10%

### **16.5. Chemotherapy side effects**

Cisplatin and carboplatin are platinum analogues. The potential side effects of platinum agents include dose-limiting myelosuppression, nausea, vomiting, renal impairment, hearing impairment, and peripheral neuropathy. Pemetrexed is an antifolate compound. Potential side effects include myelosuppression, nausea, skin rash, alopecia, diarrhoea, and fatigue.

### **17. Molecular target therapy**

Recent anticancer agents focus on molecular targets such as surface receptors and cellsignalling proteins. Although it has been shown that mesothelial cells express the vascular endothelial growth factor (VEGF) receptor, a recent study [101] failed to demonstrate survival improvement with bevacizumab. Erlotinib, a tyrosine-kinase inhibitor of the epidermal growth-factor receptor (EGFR), was tested in a phase-II trial. EGFR is expressed primarily in the epithelial subtype of mesothelioma. Of the 63 patients who were enrolled, only 29 were assessed for outcomes; no objective responses were reported [102].

### **18. Prognosis and overall survival**

The European Organisation for Research and Treatment of Cancer (EORTC) reviewed data for 204 adults who were enrolled in five consecutive phase-II trials over nine years. The EORTC poor prognostic factors [103] for mesothelioma are:


For low risk: 1-year OS rate is 40%; 2-year OS rate is 14%. For high risk: 1-year OS rate is 12% and 2-years OS rate is 0%. The MS rates are 4 and 12 months, respectively.

has a poor prognosis, but recent studies of pemetrexed and platinum-analogue combination therapies have demonstrated improved response rates over other treatments. Although conducting research on mesothelioma is extremely difficult, since it is an uncommon disease,

Mesothelioma: An Evidence-Based Review http://dx.doi.org/10.5772/55292 191

BAP1 A gene that encodes a nuclear localizing protein with a ubiquitin carboxy-terminal

further study is required to improve patient outcomes.

hydrolase domain that gives BAP1 its deubiquitinase activity.

E2F Group of genes that codifies a family of transcription factors

HCF1 A transcriptional cofactor involved in the cell cycle

EORTC European Organisation for Research and Treatment of Cancer

**Nomenclature**

AP Anterior-posterior field

CBC Complete blood count

DFS Disease-free survival

CW Chest wall

Gy Gray

MS Mean survival

OS Overall survival

CAP Cytoxan/Adriamycin/cisplatin

EGFR Epidermal growth-factor receptor

EPP Extrapleural pneumonectomy

FDA Food and Drug Administration

MVP Mitomycin, vinblastine, and cisplatin

NF-2 Neurofibromatosis type-2 gene

P14 Tumour suppressor gene P16 Tumour suppressor gene P53 Tumour suppressor gene

PA Posterior-anterior field

PS Performance status

P/D: Pleurectomy/decortication

### **19. Palliative treatment**

Surgical procedures, radiation therapy, and chemotherapy can be used to palliate symptoms.

#### **19.1. Surgery**

Large pleural effusions can cause persistent dyspnea and pain. Complete drainage of the pleural effusion by tube thoracostomy or video thoracoscopy followed by the introduction of an irritative agent to obliterate the pleural space can provide palliation. There is an ongoing randomized trial in the United Kingdom comparing the palliative benefits of VATS pleurec‐ tomy to talc pleurodesis.

#### **19.2. Radiation therapy**

In the case of palliative treatments, radiation therapy can be used for pain relief. Either 30 Gy in 10 fractions or 20 Gy in 5 fractions can be delivered. Furthermore, palliative radiation therapy with daily dose of 4 Gy appears to be more effective than fractionations of less than 4 Gy for a total dose of 20 to 40 Gy to relieve pain associated with skin nodules in the CW. Radiation therapy can alleviate symptoms in 50% of patients [104].

#### **19.3. Chemotherapy**

For unresectable tumours, palliative chemotherapy with cisplatin/pemetrexed or cisplatin/ gemcitabine can be used. There are no standard second line of chemotherapy. Therefore, a combination or single agent such as gemcitabine, vinorelbine, paclitaxel, or docetaxel may be considered.

### **20. Conclusion**

The highest risk factor for mesothelioma is exposure to asbestos. Treatment for mesothelioma involves a trimodal approach for early-stage disease, which includes surgery, radiation, and systemic chemotherapy. In the case of locally advanced disease, nonsurgical candidates, or metastatic disease, surgery, chemotherapy, or radiation therapy can be used. Mesothelioma has a poor prognosis, but recent studies of pemetrexed and platinum-analogue combination therapies have demonstrated improved response rates over other treatments. Although conducting research on mesothelioma is extremely difficult, since it is an uncommon disease, further study is required to improve patient outcomes.

### **Nomenclature**

**•** White-blood-cell count greater than 8.3 X 109/ dL

190 Cancer Treatment - Conventional and Innovative Approaches

For low risk: 1-year OS rate is 40%; 2-year OS rate is 14%. For high risk: 1-year OS rate is 12%

Surgical procedures, radiation therapy, and chemotherapy can be used to palliate symptoms.

Large pleural effusions can cause persistent dyspnea and pain. Complete drainage of the pleural effusion by tube thoracostomy or video thoracoscopy followed by the introduction of an irritative agent to obliterate the pleural space can provide palliation. There is an ongoing randomized trial in the United Kingdom comparing the palliative benefits of VATS pleurec‐

In the case of palliative treatments, radiation therapy can be used for pain relief. Either 30 Gy in 10 fractions or 20 Gy in 5 fractions can be delivered. Furthermore, palliative radiation therapy with daily dose of 4 Gy appears to be more effective than fractionations of less than 4 Gy for a total dose of 20 to 40 Gy to relieve pain associated with skin nodules in the CW.

For unresectable tumours, palliative chemotherapy with cisplatin/pemetrexed or cisplatin/ gemcitabine can be used. There are no standard second line of chemotherapy. Therefore, a combination or single agent such as gemcitabine, vinorelbine, paclitaxel, or docetaxel may be

The highest risk factor for mesothelioma is exposure to asbestos. Treatment for mesothelioma involves a trimodal approach for early-stage disease, which includes surgery, radiation, and systemic chemotherapy. In the case of locally advanced disease, nonsurgical candidates, or metastatic disease, surgery, chemotherapy, or radiation therapy can be used. Mesothelioma

Radiation therapy can alleviate symptoms in 50% of patients [104].

and 2-years OS rate is 0%. The MS rates are 4 and 12 months, respectively.

**•** Performance status (PS) 1-2

**19. Palliative treatment**

tomy to talc pleurodesis.

**19.2. Radiation therapy**

**19.3. Chemotherapy**

considered.

**20. Conclusion**

**•** Sarcomatous histology

**•** Male gender

**19.1. Surgery**

AP Anterior-posterior field

BAP1 A gene that encodes a nuclear localizing protein with a ubiquitin carboxy-terminal hydrolase domain that gives BAP1 its deubiquitinase activity.

CAP Cytoxan/Adriamycin/cisplatin

CBC Complete blood count

CW Chest wall

DFS Disease-free survival

E2F Group of genes that codifies a family of transcription factors

EGFR Epidermal growth-factor receptor

EORTC European Organisation for Research and Treatment of Cancer

EPP Extrapleural pneumonectomy

FDA Food and Drug Administration

Gy Gray

HCF1 A transcriptional cofactor involved in the cell cycle

MS Mean survival

MVP Mitomycin, vinblastine, and cisplatin

NF-2 Neurofibromatosis type-2 gene

OS Overall survival

P14 Tumour suppressor gene

P16 Tumour suppressor gene

P53 Tumour suppressor gene

PA Posterior-anterior field

P/D: Pleurectomy/decortication

PS Performance status

RT Radiation therapy VATS Video-assisted thoracoscopic surgery VEGF Vascular endothelial growth factor WT1 Wilm's tumour gene

### **Author details**

Julie Goudreault and Anne Dagnault

Department of Radiation Oncology, Hôtel-Dieu de Québec, Laval University, Canada

### **References**

[1] Pass HI, Carbone M. Malignant mesothelioma: Advances in pathogenesis, diagnosis, and translational therapies. Springer Verlag; 2005a.

[10] Institut national de santé publique Québec. Dossier amiante; Available from: http:// www.inspq.qc.ca/dossiers/amiante/infos.asp?e=cp. Accessed 28 July 2012.

Mesothelioma: An Evidence-Based Review http://dx.doi.org/10.5772/55292 193

[11] Selikoff IJ, Hammond EC, Seidman H. Latency of asbestos disease among insulation workers in the United States and Canada. Cancer 1980, Dec 15;46(12):2736-40.

[12] Boffetta P, Epidemiology of peritoneal mesothelioma: a review. Ann Oncol.

[13] Wagner JC, Sleggs CA, Marchand P. Diffuse pleural mesothelioma and asbestos ex‐ posure in the north western cape province. Br J Ind Med 1960, Oct; 17: 260-71.

[14] Occupational Safety & Heath Administration. Occupational Exposure to Asbestos; Available from http://www.osha.gov/pls/oshaweb/owadisp.show\_document?p\_ta‐

[15] Metintas M, Ozdemir N, Hillerdal G, Uçgun I, Metintas S, Baykul C, et al. Environ‐ mental asbestos exposure and malignant pleural mesothelioma. Respir Med 1999,

[16] Senyiğit A, Babayiğit C, Gökirmak M, Topçu F, Asan E, Coşkunsel M, et al. Incidence of malignant pleural mesothelioma due to environmental asbestos fiber exposure in

[17] Senyiğit A, Bayram H, Babayiğit C, Topçu F, Nazaroğlu H, Bilici A, Leblebici IH. Ma‐ lignant pleural mesothelioma caused by environmental exposure to asbestos in the southeast of Turkey: CT findings in 117 patients. Respiration 2000;67(6):615-22. [18] Metintas S, Metintas M, Ucgun I, Oner U. Malignant mesothelioma due to environ‐ mental exposure to asbestos: Follow-up of a turkish cohort living in a rural area.

[19] Pan XL, Dan Hw, Wang W et al. Residential proximity to naturally occuring asbestos and mesothelioma risk in California. Am J Respir Crit Care Med 2005; 172: 1019. [20] Hansen J, de Klerk NH, Musk AW, Hobbs MS. Environmental exposure to crocido‐ lite and mesothelioma: exposure-response relationships. AM J Respi Crit care MEd

[21] Pira E, Pelucchi C, Buffoni L et al. Cancer mortality in a cohort of asbestos textile

[22] Carbone M, Kratzke RA, Testa JR. The pathogenesis of mesothelioma. Semin Oncol

[23] Health Canada. Health risks of asbestos; Available from: http://www.hc-sc.gc.ca/hlvs/alt\_formats/pacrb-dgapcr/pdf/iyh-vsv/environ/asbestos-amiante-eng.pdf. Ac‐

ble=FEDERAL\_REGISTER&p\_id=12429 . Accessed November 27 2012.

the southeast of turkey. Respiration 2000;67(6):610-4.

2007;18(6):985.

May;93(5):349-55.

Chest 2002, Dec;122(6):2224-9

workers. Br J Cancer 2005; 92:580.

1998; 157:69.

2002, Feb;29(1):2-17.

cessed 27 July 2012.


[10] Institut national de santé publique Québec. Dossier amiante; Available from: http:// www.inspq.qc.ca/dossiers/amiante/infos.asp?e=cp. Accessed 28 July 2012.

RT Radiation therapy

WT1 Wilm's tumour gene

**Author details**

**References**

VATS Video-assisted thoracoscopic surgery

192 Cancer Treatment - Conventional and Innovative Approaches

VEGF Vascular endothelial growth factor

Julie Goudreault and Anne Dagnault

Oct 13;353(15):1591-603.

Phys 1982, Jan;8(1):19-25.

Department of Radiation Oncology, Hôtel-Dieu de Québec, Laval University, Canada

and translational therapies. Springer Verlag; 2005a.

lioma. Chest 1993, Apr;103(4 Suppl):382S-4S.

patients. Thorax 1976, Feb;31(1):15-24.

World J Surg 2001, Feb;25(2):210-7.

vasc Surg 1991, Jul;102(1):1-9.

[1] Pass HI, Carbone M. Malignant mesothelioma: Advances in pathogenesis, diagnosis,

[2] Robinson BW, Lake RA. Advances in malignant mesothelioma. N Engl J Med 2005,

[3] Gordon W, Antman KH, Greenberger JS, Weichselbaum RR, Chaffey JT. Radiation therapy in the management of patients with mesothelioma. Int J Radiat Oncol Biol

[4] Rusch VW. Pleurectomy/decortication and adjuvant therapy for malignant mesothe‐

[5] Butchart EG, Ashcroft T, Barnsley WC, Holden MP. Pleuropneumonectomy in the management of diffuse malignant mesothelioma of the pleura. Experience with 29

[6] Jaklitsch MT, Grondin SC, Sugarbaker DJ. Treatment of malignant mesothelioma.

[7] Rusch VW, Piantadosi S, Holmes EC. The role of extrapleural pneumonectomy in malignant pleural mesothelioma. A lung cancer study group trial. J Thorac Cardio‐

[8] Lung Tumour Group. B.C. Cancer agency; Available from: http://www.bccanc‐ er.bc.ca/PPI/TypesofCancer/Mesothelioma/default.htm. Accessed 5 May 2012.

[9] Connelly RR, Spirtas R, Myers MH, et al:Demographic patterns for mesothelioma in

the United States. J Natl Cancer Inst 1987; 78:1053-1060.


[24] Hodgson JT, Mc Elvenny DM, Darnton AJ, et al. The expected burden of mesothelio‐ ma mortality in Great Britain from 2002 to 2050. Br J Cancer 2005; 92:587.

[37] Pass HI, Donington JS, Wu P, Rizzo P, Nishimura M, Kennedy R, Carbone M. Hu‐ man mesotheliomas contain the simian virus-40 regulatory region and large tumor

Mesothelioma: An Evidence-Based Review http://dx.doi.org/10.5772/55292 195

[38] Ramael M, Nagels J, Heylen H, De Schepper S, Paulussen J, De Maeyer M, Van Hae‐ sendonck C. Detection of SV40 like viral DNA and viral antigens in malignant pleu‐

[39] McLaren BR, Haenel T, Stevenson S, Mukherjee S, Robinson BW, Lake RA. Simian virus (SV) 40 like sequences in cell lines and tumour biopsies from australian malig‐

[40] Gazdar AF, Carbone M. Molecular pathogenesis of malignant mesothelioma and its

[41] Kushitani K, Takeshima Y, Amatya VJ, Furonaka O, Sakatani A, Inai K. Immunohis‐ tochemical marker panels for distinguishing between epithelioid mesothelioma and

[42] Kamp DW, Israbian VA, Preusen SE, Zhang CX, Weitzman SA. Asbestos causes DNA strand breaks in cultured pulmonary epithelial cells: Role of iron-catalyzed free

[43] Ault JG, Cole RW, Jensen CG, Jensen LC, Bachert LA, Rieder CL. Behavior of croci‐ dolite asbestos during mitosis in living vertebrate lung epithelial cells. Cancer Res

[44] Adachi Y, Aoki C, Yoshio-Hoshino N, Takayama K, Curiel DT, Nishimoto N. Inter‐ leukin-6 induces both cell growth and VEGF production in malignant mesothelio‐

[45] Pisani RJ, Colby TV, Williams DE. Malignant mesothelioma of the pleura. Mayo Clin

[46] Hillerdal G. Malignant mesothelioma 1982: Review of 4710 published cases. Br J Dis

[47] Antman KH. Natural history and epidemiology of malignant mesothelioma. Chest

[48] Chang K, Pai LH, Pass H, Pogrebniak HW, Tsao MS, Pastan I, Willingham MC. Mon‐ oclonal antibody K1 reacts with epithelial mesothelioma but not with lung adenocar‐

[49] Ordóñez NG. Value of mesothelin immunostaining in the diagnosis of mesothelio‐

[50] Hollevoet K, Reitsma JB, Creaney J, Grigoriu BD, Robinson BW, Scherpereel A, et al. Serum mesothelin for diagnosing malignant pleural mesothelioma: An individual

patient data meta-analysis. J Clin Oncol 2012, May 1;30(13):1541-9.

relationship to simian virus 40. Clin Lung Cancer 2003, Nov;5(3):177-81.

antigen DNA sequences. J Thorac Cardiovasc Surg 1998, Nov;116(5):854-9.

ral mesothelioma. Eur Respir J 1999, Dec;14(6):1381-6.

nant mesotheliomas. Aust N Z J Med 2000, Aug;30(4):450-6.

lung adenocarcinoma. Pathol Int 2007, Apr;57(4):190-9.

radicals. Am J Physiol 1995, Mar;268(3 Pt 1):L471-80.

mas. Int J Cancer 2006, Sep 15;119(6):1303-11.

cinoma. Am J Surg Pathol 1992, Mar;16(3):259-68.

ma. Mod Pathol 2003, Mar;16(3):192-7.

1995, Feb 15;55(4):792-8.

Proc 1988, Dec;63(12):1234-44.

Chest 1983, Oct;77(4):321-43.

1993, Apr;103(4 Suppl):373S-6S.


[37] Pass HI, Donington JS, Wu P, Rizzo P, Nishimura M, Kennedy R, Carbone M. Hu‐ man mesotheliomas contain the simian virus-40 regulatory region and large tumor antigen DNA sequences. J Thorac Cardiovasc Surg 1998, Nov;116(5):854-9.

[24] Hodgson JT, Mc Elvenny DM, Darnton AJ, et al. The expected burden of mesothelio‐

[25] Muscat JE, Wynder EL. Cigarette smoking, asbestos exposure, and malignant meso‐

[26] Takagi A, Hirose A, Nishimura T, Fukumori N, Ogata A, Ohashi N, et al. Induction of mesothelioma in p53+/- mouse by intraperitoneal application of multi-wall carbon

[27] Poland CA, Duffin R, Kinloch I, Maynard A, Wallace WA, Seaton A, et al. Carbon nanotubes introduced into the abdominal cavity of mice show asbestos-like pathoge‐

[28] Mossman BT, Lippmann M, Hesterberg TW, Kelsey KT, Barchowsky A, Bonner JC. Pulmonary endpoints (lung carcinomas and asbestosis) following inhalation expo‐

[29] Teta MJ, Lau E, Sceurman BK, Wagner ME. Therapeutic radiation for lymphoma:

[30] Tward JD, Wendland MM, Shrieve DC, Szabo A, Gaffney DK. The risk of secondary malignancies over 30 years after the treatment of non-hodgkin lymphoma. Cancer

[31] Travis LB, Fosså SD, Schonfeld SJ, McMaster ML, Lynch CF, Storm H, et al. Second cancers among 40,576 testicular cancer patients: Focus on long-term survivors. J Natl

[32] Bott M, Brevet M, Taylor BS, Shimizu S, Ito T, Wang L, et al. The nuclear deubiquiti‐ nase BAP1 is commonly inactivated by somatic mutations and 3p21.1 losses in malig‐

[33] Testa JR, Cheung M, Pei J, Below JE, Tan Y, Sementino E, et al. Germline BAP1 muta‐ tions predispose to malignant mesothelioma. Nat Genet 2011, Oct;43(10):1022-5. [34] Altomare DA, Menges CW, Xu J, Pei J, Zhang L, Tadevosyan A, et al. Losses of both products of the cdkn2a/arf locus contribute to asbestos-induced mesothelioma devel‐ opment and cooperate to accelerate tumorigenesis. PLoS One 2011;6(4):e18828. [35] Thurneysen C, Opitz I, Kurtz S, Weder W, Stahel RA, Felley-Bosco E. Functional in‐ activation of NF2/merlin in human mesothelioma. Lung Cancer 2009, May;64(2):

[36] De Luca A, Baldi A, Esposito V, Howard CM, Bagella L, Rizzo P, et al. The retino‐ blastoma gene family prb/p105, p107, prb2/p130 and simian virus-40 large t-antigen

sure to asbestos. J Toxicol Environ Health B Crit Rev 2011;14(1-4):76-121.

Risk of malignant mesothelioma. Cancer 2007, Apr 1;109(7):1432-8.

nant pleural mesothelioma. Nat Genet 2011, Jul;43(7):668-72.

in human mesotheliomas. Nat Med 1997, Aug;3(8):913-6.

ma mortality in Great Britain from 2002 to 2050. Br J Cancer 2005; 92:587.

thelioma. Cancer Res 1991, May 1;51(9):2263-7.

194 Cancer Treatment - Conventional and Innovative Approaches

nanotube. J Toxicol Sci 2008, Feb;33(1):105-16.

2006, Jul 1;107(1):108-15.

140-7.

Cancer Inst 2005, Sep 21;97(18):1354-65.

nicity in a pilot study. Nat Nanotechnol 2008, Jul;3(7):423-8.


[51] Grigoriu BD, Scherpereel A, Devos P, Chahine B, Letourneux M, Lebailly P, et al. Utility of osteopontin and serum mesothelin in malignant pleural mesothelioma di‐ agnosis and prognosis assessment. Clin Cancer Res 2007, May 15;13(10):2928-35.

[64] Bénard F, Sterman D, Smith RJ, Kaiser LR, Albelda SM, Alavi A. Metabolic imaging of malignant pleural mesothelioma with fluorodeoxyglucose positron emission to‐

Mesothelioma: An Evidence-Based Review http://dx.doi.org/10.5772/55292 197

[65] Yildirim H, Metintas M, Entok E, Ak G, Ak I, Dundar E, Erginel S. Clinical value of fluorodeoxyglucose-positron emission tomography/computed tomography in differ‐ entiation of malignant mesothelioma from asbestos-related benign pleural disease:

[66] Curran D, Sahmoud T, Therasse P, van Meerbeeck J, Postmus PE, Giaccone G. Prog‐ nostic factors in patients with pleural mesothelioma: The european organization for research and treatment of cancer experience. J Clin Oncol 1998, Jan;16(1):145-52. [67] Balduyck B, Trousse D, Nakas A, Martin-Ucar AE, Edwards J, Waller DA. Therapeu‐ tic surgery for nonepithelioid malignant pleural mesothelioma: Is it really worth‐

[68] Baldini EH, Recht A, Strauss GM, DeCamp MM, Swanson SJ, Liptay MJ, et al. Pat‐ terns of failure after trimodality therapy for malignant pleural mesothelioma. Ann

[69] Kutcher GJ, Kestler C, Greenblatt D, Brenner H, Hilaris BS, Nori D. Technique for ex‐ ternal beam treatment for mesothelioma. Int J Radiat Oncol Biol Phys 1987, Nov;

[70] Ahamad A, Stevens CW, Smythe WR, Liao Z, Vaporciyan AA, Rice D, et al. Promis‐ ing early local control of malignant pleural mesothelioma following postoperative in‐

tensity modulated radiotherapy (IMRT) to the chest. Cancer J 2003;9(6):476-84. [71] Forster KM, Smythe WR, Starkschall G, Liao Z, Takanaka T, Kelly JF, et al. Intensitymodulated radiotherapy following extrapleural pneumonectomy for the treatment of malignant mesothelioma: Clinical implementation. Int J Radiat Oncol Biol Phys 2003,

[72] Krug LM, Pass HI, Rusch VW, Kindler HL, Sugarbaker DJ, Rosenzweig KE, et al. Multicenter phase II trial of neoadjuvant pemetrexed plus cisplatin followed by ex‐ trapleural pneumonectomy and radiation for malignant pleural mesothelioma. J Clin

[73] De Perrot M, Feld R, Cho BC, Bezjak A, Anraku M, Burkes R, et al. Trimodality thera‐ py with induction chemotherapy followed by extrapleural pneumonectomy and ad‐ juvant high-dose hemithoracic radiation for malignant pleural mesothelioma. J Clin

[74] Trousse DS, Avaro JP, D'Journo XB, Doddoli C, Astoul P, Giudicelli R, et al. Is malig‐ nant pleural mesothelioma a surgical disease? A review of 83 consecutive extra-pleu‐

ral pneumonectomies. Eur J Cardiothorac Surg 2009, Oct;36(4):759-63.

An observational pilot study. J Thorac Oncol 2009, Dec;4(12):1480-4.

mography. Chest 1998, Sep;114(3):713-22.

while? Ann Thorac Surg 2010, Mar;89(3):907-11.

Thorac Surg 1997, Feb;63(2):334-8.

Oncol 2009, Jun 20;27(18):3007-13.

Oncol 2009, Mar 20;27(9):1413-8.

13(11):1747-52.

Mar 1;55(3):606-16.


[64] Bénard F, Sterman D, Smith RJ, Kaiser LR, Albelda SM, Alavi A. Metabolic imaging of malignant pleural mesothelioma with fluorodeoxyglucose positron emission to‐ mography. Chest 1998, Sep;114(3):713-22.

[51] Grigoriu BD, Scherpereel A, Devos P, Chahine B, Letourneux M, Lebailly P, et al. Utility of osteopontin and serum mesothelin in malignant pleural mesothelioma di‐ agnosis and prognosis assessment. Clin Cancer Res 2007, May 15;13(10):2928-35.

[52] McLoud TC. CT and MR in pleural disease. Clin Chest Med 1998, Jun;19(2):261-76.

ease. AJR Am J Roentgenol 1990, Mar;154(3):487-92.

ma. AJR Am J Roentgenol 1981, Aug;137(2):287-91.

findings. Semin Roentgenol 1992, Apr;27(2):102-20.

mesothelioma. Semin Oncol 2002, Feb;29(1):26-35.

graphics 2004;24(1):105-19.

196 Cancer Treatment - Conventional and Innovative Approaches

genol 1999, Apr;172(4):1039-47.

thorac Surg 2008, Nov;34(5):1090-6.

2009, Jul;10(4):244-8.

883-91.

[53] Leung AN, Müller NL, Miller RR. CT in differential diagnosis of diffuse pleural dis‐

[54] Aberle DR, Gamsu G, Ray CS. High-resolution CT of benign asbestos-related diseas‐ es: Clinical and radiographic correlation. AJR Am J Roentgenol 1988, Nov;151(5):

[55] Alexander E, Clark RA, Colley DP, Mitchell SE. CT of malignant pleural mesothelio‐

[56] Grant DC, Seltzer SE, Antman KH, Finberg HJ, Koster K. Computed tomography of malignant pleural mesothelioma. J Comput Assist Tomogr 1983, Aug;7(4):626-32.

[57] Miller WT, Gefter WB, Miller WT. Asbestos-related chest diseases: Plain radiographic

[58] Wang ZJ, Reddy GP, Gotway MB, Higgins CB, Jablons DM, Ramaswamy M, et al. Malignant pleural mesothelioma: Evaluation with CT, MR imaging, and PET. Radio‐

[59] Heelan RT, Rusch VW, Begg CB, Panicek DM, Caravelli JF, Eisen C. Staging of malig‐ nant pleural mesothelioma: Comparison of CT and MR imaging. AJR Am J Roent‐

[60] Marom EM, Erasmus JJ, Pass HI, Patz EF. The role of imaging in malignant pleural

[61] Sørensen JB, Ravn J, Loft A, Brenøe J, Berthelsen AK, Nordic Mesothelioma Group. Preoperative staging of mesothelioma by 18f-fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography fused imaging and mediastinoscopy compared to pathological findings after extrapleural pneumonectomy. Eur J Cardio‐

[62] Plathow C, Staab A, Schmaehl A, Aschoff P, Zuna I, Pfannenberg C, et al. Computed tomography, positron emission tomography, positron emission tomography/ computed tomography, and magnetic resonance imaging for staging of limited pleu‐

[63] Wilcox BE, Subramaniam RM, Peller PJ, Aughenbaugh GL, Nichols Iii FC, Aubry MC, Jett JR. Utility of integrated computed tomography-positron emission tomogra‐ phy for selection of operable malignant pleural mesothelioma. Clin Lung Cancer

ral mesothelioma: Initial results. Invest Radiol 2008, Oct;43(10):737-44.


[75] Sugarbaker DJ, Jaklitsch MT, Bueno R, Richards W, Lukanich J, Mentzer SJ, et al. Pre‐ vention, early detection, and management of complications after 328 consecutive ex‐ trapleural pneumonectomies. J Thorac Cardiovasc Surg 2004, Jul;128(1):138-46.

[87] Lee C, Bayman N, Swindell R, Faivre-Finn C. Prophylactic radiotherapy to interven‐ tion sites in mesothelioma: A systematic review and survey of UK practice. Lung

Mesothelioma: An Evidence-Based Review http://dx.doi.org/10.5772/55292 199

[88] McAleer MF, Tsao AS, Liao Z. Radiotherapy in malignant pleural mesothelioma. Int J

[89] Boutin C, Rey F, Viallat JR. Prevention of malignant seeding after invasive diagnostic procedures in patients with pleural mesothelioma. A randomized trial of local radio‐

[90] O'Rourke N, Garcia JC, Paul J, Lawless C, McMenemin R, Hill J. A randomised con‐ trolled trial of intervention site radiotherapy in malignant pleural mesothelioma. Ra‐

[91] Froment MA, Fréchette E, Dagnault A. Prophylactic irradiation of intervention sites in malignant pleural mesothelioma. Radiother Oncol 2011, Nov;101(2):307-10. [92] Berghmans T, Paesmans M, Lalami Y, Louviaux I, Luce S, Mascaux C, et al. Activity of chemotherapy and immunotherapy on malignant mesothelioma: A systematic re‐

view of the literature with meta-analysis. Lung Cancer 2002, Nov;38(2):111-21. [93] Sugarbaker DJ, Flores RM, Jaklitsch MT, Richards WG, Strauss GM, Corson JM, et al. Resection margins, extrapleural nodal status, and cell type determine postoperative long-term survival in trimodality therapy of malignant pleural mesothelioma: Re‐ sults in 183 patients. J Thorac Cardiovasc Surg 1999, Jan;117(1):54-63; discussion 63-5.

[94] Vogelzang NJ, Rusthoven JJ, Symanowski J, Denham C, Kaukel E, Ruffie P, et al. Phase III study of pemetrexed in combination with cisplatin versus cisplatin alone in patients with malignant pleural mesothelioma. J Clin Oncol 2003, Jul 15;21(14):

[95] Ceresoli GL, Zucali PA, Favaretto AG, Grossi F, Bidoli P, Del Conte G, et al. Phase II study of pemetrexed plus carboplatin in malignant pleural mesothelioma. J Clin On‐

[96] Castagneto B, Botta M, Aitini E, Spigno F, Degiovanni D, Alabiso O, et al. Phase II study of pemetrexed in combination with carboplatin in patients with malignant

[97] Byrne MJ, Davidson JA, Musk AW, Dewar J, van Hazel G, Buck M, et al. Cisplatin and gemcitabine treatment for malignant mesothelioma: A phase II study. J Clin On‐

[98] Favaretto AG, Aversa SM, Paccagnella A, Manzini Vde P, Palmisano V, Oniga F, et al. Gemcitabine combined with carboplatin in patients with malignant pleural meso‐

[99] Muers MF, Stephens RJ, Fisher P, Darlison L, Higgs CM, Lowry E, et al. Active symp‐ tom control with or without chemotherapy in the treatment of patients with malig‐

thelioma: A multicentric phase II study. Cancer 2003, Jun 1;97(11):2791-7.

pleural mesothelioma (MPM). Ann Oncol 2008, Feb;19(2):370-3.

Cancer 2009, Nov;66(2):150-6.

Radiat Oncol Biol Phys 2009, Oct 1;75(2):326-37.

therapy. Chest 1995, Sep;108(3):754-8.

diother Oncol 2007, Jul;84(1):18-22.

2636-44.

col 2006, Mar 20;24(9):1443-8.

col 1999, Jan;17(1):25-30.


[87] Lee C, Bayman N, Swindell R, Faivre-Finn C. Prophylactic radiotherapy to interven‐ tion sites in mesothelioma: A systematic review and survey of UK practice. Lung Cancer 2009, Nov;66(2):150-6.

[75] Sugarbaker DJ, Jaklitsch MT, Bueno R, Richards W, Lukanich J, Mentzer SJ, et al. Pre‐ vention, early detection, and management of complications after 328 consecutive ex‐ trapleural pneumonectomies. J Thorac Cardiovasc Surg 2004, Jul;128(1):138-46. [76] Flores RM, Pass HI, Seshan VE, Dycoco J, Zakowski M, Carbone M, et al. Extrapleu‐ ral pneumonectomy versus pleurectomy/decortication in the surgical management of malignant pleural mesothelioma: Results in 663 patients. J Thorac Cardiovasc Surg

[77] Aisner J. Current approach to malignant mesothelioma of the pleura. Chest 1995, Jun;

[78] Rusch VW, Rosenzweig K, Venkatraman E, Leon L, Raben A, Harrison L, et al. A phase II trial of surgical resection and adjuvant high-dose hemithoracic radiation for malignant pleural mesothelioma. J Thorac Cardiovasc Surg 2001, Oct;122(4):788-95.

[79] Maasilta P. Deterioration in lung function following hemithorax irradiation for pleu‐

[80] Hilaris BS, Nori D, Kwong E, Kutcher GJ, Martini N. Pleurectomy and intraoperative brachytherapy and postoperative radiation in the treatment of malignant pleural

[81] Lee TT, Everett DL, Shu HK, Jahan TM, Roach M, Speight JL, et al. Radical pleurecto‐ my/decortication and intraoperative radiotherapy followed by conformal radiation with or without chemotherapy for malignant pleural mesothelioma. J Thorac Cardio‐

[82] Yajnik S, Rosenzweig KE, Mychalczak B, Krug L, Flores R, Hong L, Rusch VW. Hem‐ ithoracic radiation after extrapleural pneumonectomy for malignant pleural meso‐

[83] Weder W, Kestenholz P, Taverna C, Bodis S, Lardinois D, Jerman M, Stahel RA. Neo‐ adjuvant chemotherapy followed by extrapleural pneumonectomy in malignant

[84] Rice DC, Stevens CW, Correa AM, Vaporciyan AA, Tsao A, Forster KM, et al. Out‐ comes after extrapleural pneumonectomy and intensity-modulated radiation therapy for malignant pleural mesothelioma. Ann Thorac Surg 2007, Nov;84(5):1685-92; dis‐

[85] Miles EF, Larrier NA, Kelsey CR, Hubbs JL, Ma J, Yoo S, Marks LB. Intensity-modu‐ lated radiotherapy for resected mesothelioma: The duke experience. Int J Radiat On‐

[86] Rice DC, Smythe WR, Liao Z, Guerrero T, Chang JY, McAleer MF, et al. Dose-de‐ pendent pulmonary toxicity after postoperative intensity-modulated radiotherapy for malignant pleural mesothelioma. Int J Radiat Oncol Biol Phys 2007, Oct 1;69(2):

ral mesothelioma. Int J Radiat Oncol Biol Phys 1991, Mar;20(3):433-8.

mesothelioma. Int J Radiat Oncol Biol Phys 1984, Mar;10(3):325-31.

thelioma. Int J Radiat Oncol Biol Phys 2003, Aug 1;56(5):1319-26.

pleural mesothelioma. J Clin Oncol 2004, Sep 1;22(17):3451-7.

2008, Mar;135(3):620-6, 626.e1-3.

198 Cancer Treatment - Conventional and Innovative Approaches

vasc Surg 2002, Dec;124(6):1183-9.

col Biol Phys 2008, Jul 15;71(4):1143-50.

cussion 1692-3.

350-7.

107(6 Suppl):332S-44S.


nant pleural mesothelioma (MS01): A multicentre randomised trial. Lancet 2008, May 17;371(9625):1685-94.

**Chapter 9**

**Definitive Chemo-Radiotherapy for Resectable**

Shouji Shimoyama

**1. Introduction**

http://dx.doi.org/10.5772/55501

Additional information is available at the end of the chapter

2011; Urschel et al., 2003) postoperative in-hospital mortality.

**Esophageal Cancer — Unresolved Problems Remain**

Esophageal cancer, the 8th most common cancer and 6th leading cause of cancer deaths worldwide (Jemal et al., 2010), remains an invasive disease with 5-year overall survival rates (SRs) of only 20% in the USA (Daly, et al., 1996), 13% in UK (http://info.cancerresearchuk.org/ cancerstats/types/oesophagus/survival/), and less than 10% in most parts of Europe (Keighley 2003). In Japan, an updated nationwide survey (http://ganjoho.jp/public/statistics/backnum‐ ber/2011\_en.html) has demonstrated 5-year SRs of 33% for all esophageal cancers and 43% for resected cases, while in the USA, the survivals have improved to 42% in the past decade (Rice et al., 2009). Still, these statistics consistently confirm that survival remains disappointing, with less than half of all patients surviving at 5 years. Where the disease appears resectable and patients are sufficiently fit, surgery remains the mainstay of curative therapy. However, the overall poor prognosis with esophagectomies has led to the investigation of multimodal therapies in order to improve the treatment results. Among these, preoperative chemoradiotherapy (CRT) (neoadjuvant CRT) has been developed and proved promising; nonethe‐ less, morbidity and mortality have increased. What this means is that any improvement in survival rates of complete resection or local disease control by neoadjuvant CRT happens at the expense of greater toxicity. Several meta-analysis have elucidated that preoperative CRT significantly (Fiorica et al., 2004) or at least non-significantly increased (Kranzfelder et al.,

On the other hand, evidence for CRT as a curative intent (definitive CRT: dCRT) has been established for patients with esophageal cancer who otherwise do not qualify for surgery due to disease extent and/or medical comorbidity. In Japan, dCRT for T4/M1(lymph) squamous cell cancer (SCC) achieved 1-, 2-, and 3-year SRs of 41%, 27-32%, and 22-23%, respectively, which compared well with SRs of T4 SCC undergoing resection (Ishida, et al., 2004; Japanese

> © 2013 Shimoyama; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

distribution, and reproduction in any medium, provided the original work is properly cited.

and reproduction in any medium, provided the original work is properly cited.


## **Definitive Chemo-Radiotherapy for Resectable Esophageal Cancer — Unresolved Problems Remain**

Shouji Shimoyama

nant pleural mesothelioma (MS01): A multicentre randomised trial. Lancet 2008, May

[100] Scagliotti GV, Shin DM, Kindler HL, Vasconcelles MJ, Keppler U, Manegold C, et al. Phase II study of pemetrexed with and without folic acid and vitamin B12 as frontline therapy in malignant pleural mesothelioma. J Clin Oncol 2003, Apr 15;21(8):

[101] Dowell JE, Dunphy FR, Taub RN, Gerber DE, Ngov L, Yan J, et al. A multicenter phase II study of cisplatin, pemetrexed, and bevacizumab in patients with advanced

[102] Garland LL, Rankin C, Gandara DR, Rivkin SE, Scott KM, Nagle RB, et al. Phase II study of erlotinib in patients with malignant pleural mesothelioma: A southwest on‐

[103] Bottomley A, Coens C, Efficace F, Gaafar R, Manegold C, Burgers S, et al. Symptoms and patient-reported well-being: Do they predict survival in malignant pleural meso‐ thelioma? A prognostic factor analysis of EORTC-NCIC 08983: Randomized phase III study of cisplatin with or without raltitrexed in patients with malignant pleural mes‐

[104] De Graaf-Strukowska L, van der Zee J, van Putten W, Senan S. Factors influencing the outcome of radiotherapy in malignant mesothelioma of the pleura--a single-insti‐ tution experience with 189 patients. Int J Radiat Oncol Biol Phys 1999, Feb 1;43(3):

malignant mesothelioma. Lung Cancer 2012, Jul 4.

othelioma. J Clin Oncol 2007, Dec 20;25(36):5770-6.

cology group study. J Clin Oncol 2007, Jun 10;25(17):2406-13.

17;371(9625):1685-94.

200 Cancer Treatment - Conventional and Innovative Approaches

1556-61.

511-6.

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/55501

### **1. Introduction**

Esophageal cancer, the 8th most common cancer and 6th leading cause of cancer deaths worldwide (Jemal et al., 2010), remains an invasive disease with 5-year overall survival rates (SRs) of only 20% in the USA (Daly, et al., 1996), 13% in UK (http://info.cancerresearchuk.org/ cancerstats/types/oesophagus/survival/), and less than 10% in most parts of Europe (Keighley 2003). In Japan, an updated nationwide survey (http://ganjoho.jp/public/statistics/backnum‐ ber/2011\_en.html) has demonstrated 5-year SRs of 33% for all esophageal cancers and 43% for resected cases, while in the USA, the survivals have improved to 42% in the past decade (Rice et al., 2009). Still, these statistics consistently confirm that survival remains disappointing, with less than half of all patients surviving at 5 years. Where the disease appears resectable and patients are sufficiently fit, surgery remains the mainstay of curative therapy. However, the overall poor prognosis with esophagectomies has led to the investigation of multimodal therapies in order to improve the treatment results. Among these, preoperative chemoradiotherapy (CRT) (neoadjuvant CRT) has been developed and proved promising; nonethe‐ less, morbidity and mortality have increased. What this means is that any improvement in survival rates of complete resection or local disease control by neoadjuvant CRT happens at the expense of greater toxicity. Several meta-analysis have elucidated that preoperative CRT significantly (Fiorica et al., 2004) or at least non-significantly increased (Kranzfelder et al., 2011; Urschel et al., 2003) postoperative in-hospital mortality.

On the other hand, evidence for CRT as a curative intent (definitive CRT: dCRT) has been established for patients with esophageal cancer who otherwise do not qualify for surgery due to disease extent and/or medical comorbidity. In Japan, dCRT for T4/M1(lymph) squamous cell cancer (SCC) achieved 1-, 2-, and 3-year SRs of 41%, 27-32%, and 22-23%, respectively, which compared well with SRs of T4 SCC undergoing resection (Ishida, et al., 2004; Japanese

© 2013 Shimoyama; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Society of Esophageal Diseases, 2005; Y Nishimura et al., 2002; Ohtsu, et al., 1999; Kumekawa et al., 2006) [Table 1], although they were not a nonrandomized comparison. Subsequently, three pivotal RCTs demonstrated that survival results were similar between dCRT and neoadjuvant CRT followed by surgery or surgery only. A German trial revealed that dCRT with at least 65Gy for T3-4/N0-1/M0 SCC offered similar survival results with less likelihood of treatment-related mortality as compared with neoadjuvant CRT with 40Gy radiation (Stahl, et al., 2005). A French FFCD trial recruiting T3/N0-1/M0 SCC patients found no benefit of subsequent surgery following CRT for those responding to CRT (Bedenne et al., 2007). This study has established a rationale that the response to neoadjuvant CRT is a favorable prog‐ nostic sign which allows the selection of patients most likely to benefit from dCRT, thereby indicating the potential of dCRT for organ-sparing treatments. A CURE trial conducted in China compared T2-3/N1 SCC patients undergoing standard esophagectomy with those undergoing dCRT with 50-60Gy radiation and observed no survival differences between these two treatments (Chiu et al., 2005). Consequently, a very recent meta-analysis has also eluci‐ dated that there is no trend regarding differences in overall survival between surgery and dCRT (Pöttgen et al., 2012).

**2. Definitive CRT for resectable esophageal cancer is promising and could**

Definitive Chemo-Radiotherapy for Resectable Esophageal Cancer — Unresolved Problems Remain

http://dx.doi.org/10.5772/55501

203

Many chemotherapeutic agents are potential candidates that could be combined with radiation (Kleinberg et al., 2007). Among these, the most frequently used agents are fluorouracil and cisplatin, both act as radiosensitizers. Fluorouracil inhibits DNA and RNA synthesis resulting in decreasing radiation-induced DNA injury repair, which eventually enhances radiationinduced cytotoxicity. Cisplatin forms inter- and intrastrand cross-links to DNA that impede repair. This action also leads to decrease in cellular repair in response to radiation-induced damage. Therefore, besides a direct action of fluorouracil and cisplatin to DNA, these two

Several nonrandomized comparisons have been conducted to investigate whether dCRT could achieve the same impact on survival as esophagectomy for those patients deemed suitable for surgery. More important are the encouraging results of dCRT for patients with operable rather than inoperable esophageal cancer. Table 2 lists the results of dCRT for each stage of esophageal cancer; these studies of dCRT with at least 60Gy radiation have shown consistent favorable SRs, which compare favorably with the Japan nationwide 3-year SR (44%) of surgery only (Japanese Society of Esophageal diseases, 2005). Ishikura et al. (Ishikura, et al., 2003) and Hironaka et al. (Hironaka et al., 2003) respectively recruited T1-3 (70% T3) and T2-3 SCC patients, and dCRT yielded 3-year and 5-year SRs of 49-55% and 46-49%, respectively. Three other dCRT studies revealed promising 3-year SRs which were 80% for patients with stage II SCC (Morota et al., 2009), 45% for those with stage II and III SCC (K Kato et al., 2011), and 72% for those with stage 0-III SCC (Murakami et al., 1998). These results motivated the researchers to conduct dCRT studies for less progressed esophageal SCC. For T1N0M0 stage I esophageal SCC, dCRT resulted in 1-, 2-, 3-, 4-, and 5-year SRs of 98%, 93%, 79-89%, 81%, and 66-67%, respectively, which could be compared favorably with survivals of surgical cases (H Kato et al., 2009; Minashi et al., 2006; K Yamada et al., 2006; Yamamoto et al., 2011). These findings are indeed encouraging and dCRT could be an alternative to esophagectomy. In addition, since dCRT can preserve the esophagus, it could theoretically offer better posttreatment quality of life than that for patients treated by surgery. Indeed, esophagectomy resulted in worse functional, symptomatic, and global quality of life scores at 6 weeks postoperatively than before surgery (Blazeby et al., 2000). However, the recently accumulated data on dCRT has

When considering dCRT—especially for potentially resectable esophageal cancer, risks from the treatment, i.e., treatment-related complications or death, should be taken into account in evaluating whether dCRT could substitute for surgery. Some patients undergoing dCRT have experienced severe grade 3/4 pericarditis, pleural effusion, and radiation pneumonitis, which

**be an alternative to esophagectomy**

agents and radiation act synergistically.

raised several issues of concern.

**3.1. Invasiveness of dCRT**

**3. Problems remain to be resolved**


**Table 1.** Treatment results of definitive chemo-radiotherapy for far advanced esophageal cancer in Japan.

Against these backgrounds and considering that surgery for esophageal cancer is a formida‐ bleprocedure with significant morbidity and mortality (asdiscussedin section3.1) which raises concerns about its applicability in most patients, dCRT, at first investigated with palliative intent, has been further extended to resectable cases. While there was much initial enthusi‐ asm for dCRT, notes of caution have been raised in interpreting the accumulated dCRT experience. These should be resolved for the further advancement of multimodal approaches for esophageal cancer. This chapterintroduces current problems to be taken into account when performing dCRT, especially for patients with potentially resectable esophageal cancer.

### **2. Definitive CRT for resectable esophageal cancer is promising and could be an alternative to esophagectomy**

Many chemotherapeutic agents are potential candidates that could be combined with radiation (Kleinberg et al., 2007). Among these, the most frequently used agents are fluorouracil and cisplatin, both act as radiosensitizers. Fluorouracil inhibits DNA and RNA synthesis resulting in decreasing radiation-induced DNA injury repair, which eventually enhances radiationinduced cytotoxicity. Cisplatin forms inter- and intrastrand cross-links to DNA that impede repair. This action also leads to decrease in cellular repair in response to radiation-induced damage. Therefore, besides a direct action of fluorouracil and cisplatin to DNA, these two agents and radiation act synergistically.

Several nonrandomized comparisons have been conducted to investigate whether dCRT could achieve the same impact on survival as esophagectomy for those patients deemed suitable for surgery. More important are the encouraging results of dCRT for patients with operable rather than inoperable esophageal cancer. Table 2 lists the results of dCRT for each stage of esophageal cancer; these studies of dCRT with at least 60Gy radiation have shown consistent favorable SRs, which compare favorably with the Japan nationwide 3-year SR (44%) of surgery only (Japanese Society of Esophageal diseases, 2005). Ishikura et al. (Ishikura, et al., 2003) and Hironaka et al. (Hironaka et al., 2003) respectively recruited T1-3 (70% T3) and T2-3 SCC patients, and dCRT yielded 3-year and 5-year SRs of 49-55% and 46-49%, respectively. Three other dCRT studies revealed promising 3-year SRs which were 80% for patients with stage II SCC (Morota et al., 2009), 45% for those with stage II and III SCC (K Kato et al., 2011), and 72% for those with stage 0-III SCC (Murakami et al., 1998). These results motivated the researchers to conduct dCRT studies for less progressed esophageal SCC. For T1N0M0 stage I esophageal SCC, dCRT resulted in 1-, 2-, 3-, 4-, and 5-year SRs of 98%, 93%, 79-89%, 81%, and 66-67%, respectively, which could be compared favorably with survivals of surgical cases (H Kato et al., 2009; Minashi et al., 2006; K Yamada et al., 2006; Yamamoto et al., 2011). These findings are indeed encouraging and dCRT could be an alternative to esophagectomy. In addition, since dCRT can preserve the esophagus, it could theoretically offer better posttreatment quality of life than that for patients treated by surgery. Indeed, esophagectomy resulted in worse functional, symptomatic, and global quality of life scores at 6 weeks postoperatively than before surgery (Blazeby et al., 2000). However, the recently accumulated data on dCRT has raised several issues of concern.

### **3. Problems remain to be resolved**

### **3.1. Invasiveness of dCRT**

Society of Esophageal Diseases, 2005; Y Nishimura et al., 2002; Ohtsu, et al., 1999; Kumekawa et al., 2006) [Table 1], although they were not a nonrandomized comparison. Subsequently, three pivotal RCTs demonstrated that survival results were similar between dCRT and neoadjuvant CRT followed by surgery or surgery only. A German trial revealed that dCRT with at least 65Gy for T3-4/N0-1/M0 SCC offered similar survival results with less likelihood of treatment-related mortality as compared with neoadjuvant CRT with 40Gy radiation (Stahl, et al., 2005). A French FFCD trial recruiting T3/N0-1/M0 SCC patients found no benefit of subsequent surgery following CRT for those responding to CRT (Bedenne et al., 2007). This study has established a rationale that the response to neoadjuvant CRT is a favorable prog‐ nostic sign which allows the selection of patients most likely to benefit from dCRT, thereby indicating the potential of dCRT for organ-sparing treatments. A CURE trial conducted in China compared T2-3/N1 SCC patients undergoing standard esophagectomy with those undergoing dCRT with 50-60Gy radiation and observed no survival differences between these two treatments (Chiu et al., 2005). Consequently, a very recent meta-analysis has also eluci‐ dated that there is no trend regarding differences in overall survival between surgery and

> **Number of patients**

Cisplatin SCC <sup>28</sup> 32%

**Table 1.** Treatment results of definitive chemo-radiotherapy for far advanced esophageal cancer in Japan.

Against these backgrounds and considering that surgery for esophageal cancer is a formida‐ bleprocedure with significant morbidity and mortality (asdiscussedin section3.1) which raises concerns about its applicability in most patients, dCRT, at first investigated with palliative intent, has been further extended to resectable cases. While there was much initial enthusi‐ asm for dCRT, notes of caution have been raised in interpreting the accumulated dCRT experience. These should be resolved for the further advancement of multimodal approaches for esophageal cancer. This chapterintroduces current problems to be taken into account when performing dCRT, especially for patients with potentially resectable esophageal cancer.

Cisplatin SCC <sup>54</sup> 33% <sup>9</sup> 1YSR=41%

**Complete response rate**

Cisplatin SCC <sup>60</sup> 15% <sup>10</sup> 2YSR=32% 1.7%

Cisplatin SCC <sup>81</sup> 42% <sup>14</sup> 1YSR=62%

**Median survival time (months)**

> stage III=12 stage IV=5

**Survival**

3YSR=23% 6.8%

2YSR=27% NA

3YSR=22% 11.8%

**Tretmentrelated death**

dCRT (Pöttgen et al., 2012).

**stage**

T4 N0-1

T4 and/or

T1-4 and

**Radiation**

202 Cancer Treatment - Conventional and Innovative Approaches

M1 lymph 60 Gy Fluorouracil

M0-1 60 Gy Fluorouracil

M1 lymph 60 Gy Fluorouracil

M1lymph 60 Gy Fluorouracil

**dose Chemotherapy Histology**

**Author Tumor**

Ohtsu, 1999 T4 and/or

Nishimura, 2002

Ishida, 2004 (JCOG9516)

Kumekawa, 2006

YSR; year survival rate

When considering dCRT—especially for potentially resectable esophageal cancer, risks from the treatment, i.e., treatment-related complications or death, should be taken into account in evaluating whether dCRT could substitute for surgery. Some patients undergoing dCRT have experienced severe grade 3/4 pericarditis, pleural effusion, and radiation pneumonitis, which


treatment-related death at a rate of 3-14% of the study population (K Kato et al., 2011; Morota et al., 2009; Sai et al., 2004; Sasamoto et al., 2007; Yamashita et al., 2008) or 8-12% of the CR patients (Ishihara et al., 2010; Ishikura et al., 2003; Kumekawa et al., 2006; Minashi et al., 2006; Sasamoto et al., 2007) [Table 3]. Especially, 8% of treatment-related death among the CR patients with stage I disease (Minashi et al., 2006) cannot be overlooked because they would

Definitive Chemo-Radiotherapy for Resectable Esophageal Cancer — Unresolved Problems Remain

Hironaka, 2003 10.8%\* 13.5%\* 8.1%\* 0.0% ND Ishihara, 2010 NA 0.9%\*\* 2.7%\*\* ND 8.2% Ishikura, 2003 5.8% 5.8% 2.2% ND 10.3% Kato, 2011 (JCOG9906) 16.0% 9.0% 4.0% 5.3% ND Kumekawa, 2006 3.7% 3.7% 1.2% ND 11.8% Li , 2010 NA 6.8% NA ND ND Minashi, 2006 2.8%\* 11.1%\* 0.0% ND 8.3% Morota, 2009 1.4% 1.4% 1.4% 2.9% ND Sai, 2004 NA NA 13.8% 13.8% ND Sasamoto, 2007 8.9% 8.9% NA 7.1% 7.1% Yamamoto, 2011 0.0% 0.0% 3.7% ND ND Yamashita, 2008 NA NA 6.1% 6.1% ND

The heart is susceptible to radiation injury. Pericardial damage is most frequently mentioned, but all structures of the heart are at risk. Mediastinal radiation causes inflammation and progressive fibrosis of all of the structures of this organ. A worsening of clinical severity with increased radiation volume has been suggested. The risk of pericarditis has been found to rise with increased total dose and larger dose per fraction, reaching 3-fold and 2-fold greater relative risks at total doses of 41 Gy or greater, or a dose per fraction of 3.0 Gy or greater, respectively (Cosset et al., 1991). Another study also demonstrated that larger fraction size has a significant relationship with the chance of pericarditis (Martel et al., 1998 ). These observa‐ tions suggest that dose effect as well as fractionation effect account for the increased risk of

Radiation pneumonitis has been reported in patients who have undergone mediastinal radiation therapy for various diseases. The risks of radiation pneumonitis rise when radio‐

**Grade 3/4 Toxicities Tretment-related death**

http://dx.doi.org/10.5772/55501

205

**Pericarditis Pleural effusion Pneumonitis of all patients of CR patients**

be expected to survive by surgery unless fatal complications occurred.

**Author**

\*among the complete responders, \*\*death rate ND; not described, CR; complete response

pericarditis.

**Table 3.** Mortality and late morbidity of definitive chemo-radiotherapy.

SCC; squamous cell cancer, YSR; year survival rate

ND; not described

**Table 2.** Treatment results of definitive chemo-radiotherapy for potentially resectable esophageal cancer.

respectively developed in 1.4-16% (Hironaka et al., 2003; Ishikura et al., 2003; K Kato et al., 2011; Kumekawa et al., 2006; Minashi et al., 2006; Morota et al., 2009; Sasamoto et al., 2007), 1.4-14% (Hironaka et al., 2003;, Ishihara et al., 2010; Ishikura et al., 2003; K Kato et al., 2011; Kumekawa et al., 2006; Li et al., 2010; Minashi et al., 2006; Morota et al., 2009; Sasamoto et al., 2007), and 1.2-14% (Hironaka et al., 2003;, Ishihara et al., 2010; Ishikura et al., 2003; K Kato et al., 2011; Kumekawa et al., 2006; Morota et al., 2009; Sai et al., 2004; Yamamoto et al., 2011; Yamashita et al., 2008) of the study population. These complications eventually caused treatment-related death at a rate of 3-14% of the study population (K Kato et al., 2011; Morota et al., 2009; Sai et al., 2004; Sasamoto et al., 2007; Yamashita et al., 2008) or 8-12% of the CR patients (Ishihara et al., 2010; Ishikura et al., 2003; Kumekawa et al., 2006; Minashi et al., 2006; Sasamoto et al., 2007) [Table 3]. Especially, 8% of treatment-related death among the CR patients with stage I disease (Minashi et al., 2006) cannot be overlooked because they would be expected to survive by surgery unless fatal complications occurred.


\*among the complete responders, \*\*death rate

ND; not described, CR; complete response

respectively developed in 1.4-16% (Hironaka et al., 2003; Ishikura et al., 2003; K Kato et al., 2011; Kumekawa et al., 2006; Minashi et al., 2006; Morota et al., 2009; Sasamoto et al., 2007), 1.4-14% (Hironaka et al., 2003;, Ishihara et al., 2010; Ishikura et al., 2003; K Kato et al., 2011; Kumekawa et al., 2006; Li et al., 2010; Minashi et al., 2006; Morota et al., 2009; Sasamoto et al., 2007), and 1.2-14% (Hironaka et al., 2003;, Ishihara et al., 2010; Ishikura et al., 2003; K Kato et al., 2011; Kumekawa et al., 2006; Morota et al., 2009; Sai et al., 2004; Yamamoto et al., 2011; Yamashita et al., 2008) of the study population. These complications eventually caused

**Table 2.** Treatment results of definitive chemo-radiotherapy for potentially resectable esophageal cancer.

**Author Tumor**

Hironaka, 2003 T2-3 N

Ishikura, 2003 T1-3,M0

**Advanced cancer**

Kato, 2011

Murakami,

Yamamoto,

ND; not described

**T1 cancer** Kato, 2009 **stage**

204 Cancer Treatment - Conventional and Innovative Approaches

**Radiation**

any M0 60Gy Fluorouracil

(70% T3) 60Gy Fluorouracil

(JCOG9906) II and III 60Gy Fluorouracil

Morota, 2009 I-IVB 60Gy Fluorouracil

<sup>1998</sup> 0-III 60-75Gy Fluorouracil

(JCOG9708) T1N0M0 30Gy Fluorouracil

Minashi, 2006 T1N0M0 60Gy Fluorouracil

Yamada, 2006 T1N0M0 55-66Gy Fluorouracil

<sup>2011</sup> T1N0M0 60Gy Fluorouracil

SCC; squamous cell cancer, YSR; year survival rate

**dose Chemotherapy Histology**

**Number of patients**

Cisplatin SCC <sup>53</sup> 37(70%) <sup>33</sup> 3YSR=49%

Cisplatin SCC <sup>67</sup> ND <sup>44</sup> 3YSR=55%

Cisplatin SCC <sup>76</sup> 46(62%) <sup>29</sup> 3YSR=45%

Cisplatin SCC <sup>69</sup> 36(52.2%) ND

Cisplatin SCC <sup>30</sup> 16(53.3%) not

Cisplatin SCC <sup>72</sup> 63(88%) not

Cisplatin SCC <sup>41</sup> 36(88%) not

Cisplatin SCC <sup>54</sup> ND

Cisplatin SCC <sup>63</sup> ND ND 5YSR=66%

**Complete responders (%)**

**Median survival time (months)**

reached

reached

reached

not reached **Survival**

5YSR=46%

5YSR=49%

5YSR=37%

stage I 3YSR=80% stage II 3YSR=80% stage III 3YSR=30% stage IV 3YSR=30%

2YSR=81% 3YSR=72%

2YSR=93% 4YSR=81%

1YSR=98% 3YSR=79% 5YSR=67%

1YSR=98% 3YSR=89%

**Table 3.** Mortality and late morbidity of definitive chemo-radiotherapy.

The heart is susceptible to radiation injury. Pericardial damage is most frequently mentioned, but all structures of the heart are at risk. Mediastinal radiation causes inflammation and progressive fibrosis of all of the structures of this organ. A worsening of clinical severity with increased radiation volume has been suggested. The risk of pericarditis has been found to rise with increased total dose and larger dose per fraction, reaching 3-fold and 2-fold greater relative risks at total doses of 41 Gy or greater, or a dose per fraction of 3.0 Gy or greater, respectively (Cosset et al., 1991). Another study also demonstrated that larger fraction size has a significant relationship with the chance of pericarditis (Martel et al., 1998 ). These observa‐ tions suggest that dose effect as well as fractionation effect account for the increased risk of pericarditis.

Radiation pneumonitis has been reported in patients who have undergone mediastinal radiation therapy for various diseases. The risks of radiation pneumonitis rise when radio‐ therapy is combined with chemotherapy (McDonald et al., 1995; M Yamada et al., 1998). The risks of lung toxicity appear to be related to dose-volume parameters such as the irradiated lung volume, mean lung dose (Hernando et al., 2001), total dose (Roach et al., 1995), daily fraction dose (Roach et al., 1995), and number of daily fractions (Roach et al., 1995), —although there are some inconsistencies (Allen et al., 2003). Similarly, the percentage of lungs receiving a specified dose has also been reported to be a predictor of pneumonitis (Madani et al., 2007; Tsujino et al., 2003).

The study period is also a determinant. Single institutions in the USA (Orringer et al., 2007) or Italy (Ruol et al., 2009) experienced consistently decreased hospital mortality from 4% to 1% (Orringer et al., 2007) or from 8.2% to 2.6% (Ruol et al., 2009). Taking into account the various determinants of hospital mortality, the treatment-related death rates of 8-12% among CR patients of dCRT are undoubtedly higher than those of surgical mortality in Japan, but equal to or lower than in some countries. Considering the balance between the risks of dCRT and those of surgery, dCRT is regarded as a risky treatment as compared with surgery in some

Definitive Chemo-Radiotherapy for Resectable Esophageal Cancer — Unresolved Problems Remain

http://dx.doi.org/10.5772/55501

207

The lack of any definitive diagnostic methods currently available for the response evaluation after dCRT remain pressing issues following dCRT. Strikingly, some segments of patients who underwent surgery following dCRT due to persistent disease proved to be complete respond‐ ers postoperatively. The rates of such seemingly unnecessary salvage surgery are 10-50% (Ariga, et al., 2009; Beseth et al., 2000; Lim et al., 2003; Murakami et al., 1998; M Nishimura et al., 2007; Tachimori et al., 2009; Wilson et al., 2002). On the other hand, clinically diagnosed CR patients sometimes prove to have residual diseases and eventually exhibit relapse. The rates of overall recurrence or local recurrence after CR are substantial, being respectively 19-67% and 14-40% (Di Fiore et al., 2006; Ishihara et al., 2010; Kumekawa et al., 2006; Minashi et al., 2006; Morota et al., 2009; Murakami et al., 1998; Takeuchi et al., 2007; Tougeron et al., 2008; Wilson et al., 2000) [Table 4], suggesting that patients whose tumor response is deemed complete after dCRT could have residual diseases and that clinically CR is not always a reason to preclude further additional treatment. Such local recurrence rates do not depend on the initial tumor stage or depth. These discrepancies may be ascribed to the limitations of current

There are several diagnostic tools for evaluating responses to CRT. Endoscopy is an easily available means of investigation, but its accuracy is low as recurrent or residual tumors often lie beneath the mucosa [Figure 1]. Negative endoscopy findings have sometimes included microscopic foci of a residual tumor in the resected esophagus specimens. Moreover, the differentiation between tumor and radiation changes is not easy. A false negative rate of 48% for biopsy by endoscopy (Jones et al., 1997) suggests a poor correlation between endoscopic

Endoscopic ultrasonography (EUS) also cannot reliably distinguish a residual tumor from postinflammatory changes, which is, on the other hand, a characteristic of the efficacy of dCRT. Even in earlier reports demonstrating the efficacy of EUS, (Hirata et al., 1997; Willis et al., 2002), it should be noted that a perfect discrimination between T0 and T1 tumors was not a consideration) since a certain degree of remaining tumor (<50-70%) was considered an EUSbased response, or a scattered or even a remaining degree of 1/3< viable cells was considered a pathological response. Such a cut-off value is less useful for deciding the need for salvage surgery following dCRT because only patients with no viable cells could theoretically be escaped from salvage surgery. EUS T staging accuracy after neoadjuvant CRT was only 43%,

countries or in some institutions where surgery can be performed more safely.

**3.2. Response evaluation is not necessarily perfect**

imaging methods.

findings and pathologic status.

The obstruction of cardiac and mediastinal lymphatic vessels due to radiation fibrosis has been postulated as a possible etiology of radiation-induced pericardial and pleural effusions. As a result, radiation-induced cardiac or lung disease is responsible for a certain fraction of death not directly attributable to esophageal cancer itself in some patients who would survive if they could have undergone surgery without complications. Although nonsurgical approaches are appealing in trying to manage this difficult disease, it is a fact that there is a fine therapeutic window because of the significant toxicities, and the toxicity may outweigh any potential advantages.

If treatment-related morbidity and mortality of dCRT exceed those of surgery, the benefits of dCRT may be cancelled. Therefore, the risk balance between dCRT and surgery should be taken into account in consideration of dCRT; however, one should remember that the mor‐ bidity and mortality of esophagectomy differ considerably between countries. Surgical mortality was 2-4% in Japan (Fujita et al., 2010; Suzuki et al., 2011; Tachimori et al., 2009), while 4.2-7.6% in Taiwan (Lin et al., 2006), 6% in Italy (Ruol et al., 2009), 4-13% in the Netherlands (Steyerberg et al., 2006; Wouters et al., 2008), and 6-23% in the USA (Atkins et al., 2004; Bailey et al., 2003; Birkmeyer et al., 2002; Dimick et al., 2005; Finks et al., 2011; Rentz et al., 2003), suggesting that differences in surgical mortality between countries can be more than doubled or quadrupled.

However, the risk comparison between dCRT and surgery should require considerations of the hospital volume, surgeon volume, specialization, study period, and country, i.e., when and where the studies of dCRT are conducted, as well as the number of esphagectomies that each surgeon performs. With regard to hospital volume, even in the USA —where surgical mortality is generally high, hospital mortality after esophagectomy varied from 23% for institutions undertaking <2 cases per annum to 8% for those undertaking 20 or more cases per annum (Birkmeyer et al., 2002). In Japan, the average mortality was 1.8% when >51 esophagectomies per annum were undertaken, compared with 4.6% if 20 or fewer esophagectomies were performed per annum (Suzuki et al., 2011). Fujita et al. (Fujita et al., 2010) and Kazui et al. (Kazui et al., 2007) also reported a larger hospital volume with a lower 30-day or in-hospital mortality rates. The same volume-outcome relationship was also observed in Taiwan (Lin et al., 2006) and the Netherlands (Wouters et al., 2008). In addition, high volume surgeons experienced a 4.2% mortality rate, which was one-quarter of that of low volume surgeons, approaching the average in-hospital mortality in Japan (Migliore et al., 2007). Also in Japan, risk of morbidity by low volume surgeons is twice that of high volume surgeons (Yasunaga et al., 2009). Collectively, a larger experience of esophagectomies could significantly reduce the 30-day or in-hospital mortality from 18% to 5% (Metzger et al., 2004).

The study period is also a determinant. Single institutions in the USA (Orringer et al., 2007) or Italy (Ruol et al., 2009) experienced consistently decreased hospital mortality from 4% to 1% (Orringer et al., 2007) or from 8.2% to 2.6% (Ruol et al., 2009). Taking into account the various determinants of hospital mortality, the treatment-related death rates of 8-12% among CR patients of dCRT are undoubtedly higher than those of surgical mortality in Japan, but equal to or lower than in some countries. Considering the balance between the risks of dCRT and those of surgery, dCRT is regarded as a risky treatment as compared with surgery in some countries or in some institutions where surgery can be performed more safely.

### **3.2. Response evaluation is not necessarily perfect**

therapy is combined with chemotherapy (McDonald et al., 1995; M Yamada et al., 1998). The risks of lung toxicity appear to be related to dose-volume parameters such as the irradiated lung volume, mean lung dose (Hernando et al., 2001), total dose (Roach et al., 1995), daily fraction dose (Roach et al., 1995), and number of daily fractions (Roach et al., 1995), —although there are some inconsistencies (Allen et al., 2003). Similarly, the percentage of lungs receiving a specified dose has also been reported to be a predictor of pneumonitis (Madani et al., 2007;

The obstruction of cardiac and mediastinal lymphatic vessels due to radiation fibrosis has been postulated as a possible etiology of radiation-induced pericardial and pleural effusions. As a result, radiation-induced cardiac or lung disease is responsible for a certain fraction of death not directly attributable to esophageal cancer itself in some patients who would survive if they could have undergone surgery without complications. Although nonsurgical approaches are appealing in trying to manage this difficult disease, it is a fact that there is a fine therapeutic window because of the significant toxicities, and the toxicity may outweigh any potential

If treatment-related morbidity and mortality of dCRT exceed those of surgery, the benefits of dCRT may be cancelled. Therefore, the risk balance between dCRT and surgery should be taken into account in consideration of dCRT; however, one should remember that the mor‐ bidity and mortality of esophagectomy differ considerably between countries. Surgical mortality was 2-4% in Japan (Fujita et al., 2010; Suzuki et al., 2011; Tachimori et al., 2009), while 4.2-7.6% in Taiwan (Lin et al., 2006), 6% in Italy (Ruol et al., 2009), 4-13% in the Netherlands (Steyerberg et al., 2006; Wouters et al., 2008), and 6-23% in the USA (Atkins et al., 2004; Bailey et al., 2003; Birkmeyer et al., 2002; Dimick et al., 2005; Finks et al., 2011; Rentz et al., 2003), suggesting that differences in surgical mortality between countries can be more than doubled

However, the risk comparison between dCRT and surgery should require considerations of the hospital volume, surgeon volume, specialization, study period, and country, i.e., when and where the studies of dCRT are conducted, as well as the number of esphagectomies that each surgeon performs. With regard to hospital volume, even in the USA —where surgical mortality is generally high, hospital mortality after esophagectomy varied from 23% for institutions undertaking <2 cases per annum to 8% for those undertaking 20 or more cases per annum (Birkmeyer et al., 2002). In Japan, the average mortality was 1.8% when >51 esophagectomies per annum were undertaken, compared with 4.6% if 20 or fewer esophagectomies were performed per annum (Suzuki et al., 2011). Fujita et al. (Fujita et al., 2010) and Kazui et al. (Kazui et al., 2007) also reported a larger hospital volume with a lower 30-day or in-hospital mortality rates. The same volume-outcome relationship was also observed in Taiwan (Lin et al., 2006) and the Netherlands (Wouters et al., 2008). In addition, high volume surgeons experienced a 4.2% mortality rate, which was one-quarter of that of low volume surgeons, approaching the average in-hospital mortality in Japan (Migliore et al., 2007). Also in Japan, risk of morbidity by low volume surgeons is twice that of high volume surgeons (Yasunaga et al., 2009). Collectively, a larger experience of esophagectomies could significantly reduce the

30-day or in-hospital mortality from 18% to 5% (Metzger et al., 2004).

Tsujino et al., 2003).

206 Cancer Treatment - Conventional and Innovative Approaches

advantages.

or quadrupled.

The lack of any definitive diagnostic methods currently available for the response evaluation after dCRT remain pressing issues following dCRT. Strikingly, some segments of patients who underwent surgery following dCRT due to persistent disease proved to be complete respond‐ ers postoperatively. The rates of such seemingly unnecessary salvage surgery are 10-50% (Ariga, et al., 2009; Beseth et al., 2000; Lim et al., 2003; Murakami et al., 1998; M Nishimura et al., 2007; Tachimori et al., 2009; Wilson et al., 2002). On the other hand, clinically diagnosed CR patients sometimes prove to have residual diseases and eventually exhibit relapse. The rates of overall recurrence or local recurrence after CR are substantial, being respectively 19-67% and 14-40% (Di Fiore et al., 2006; Ishihara et al., 2010; Kumekawa et al., 2006; Minashi et al., 2006; Morota et al., 2009; Murakami et al., 1998; Takeuchi et al., 2007; Tougeron et al., 2008; Wilson et al., 2000) [Table 4], suggesting that patients whose tumor response is deemed complete after dCRT could have residual diseases and that clinically CR is not always a reason to preclude further additional treatment. Such local recurrence rates do not depend on the initial tumor stage or depth. These discrepancies may be ascribed to the limitations of current imaging methods.

There are several diagnostic tools for evaluating responses to CRT. Endoscopy is an easily available means of investigation, but its accuracy is low as recurrent or residual tumors often lie beneath the mucosa [Figure 1]. Negative endoscopy findings have sometimes included microscopic foci of a residual tumor in the resected esophagus specimens. Moreover, the differentiation between tumor and radiation changes is not easy. A false negative rate of 48% for biopsy by endoscopy (Jones et al., 1997) suggests a poor correlation between endoscopic findings and pathologic status.

Endoscopic ultrasonography (EUS) also cannot reliably distinguish a residual tumor from postinflammatory changes, which is, on the other hand, a characteristic of the efficacy of dCRT. Even in earlier reports demonstrating the efficacy of EUS, (Hirata et al., 1997; Willis et al., 2002), it should be noted that a perfect discrimination between T0 and T1 tumors was not a consideration) since a certain degree of remaining tumor (<50-70%) was considered an EUSbased response, or a scattered or even a remaining degree of 1/3< viable cells was considered a pathological response. Such a cut-off value is less useful for deciding the need for salvage surgery following dCRT because only patients with no viable cells could theoretically be escaped from salvage surgery. EUS T staging accuracy after neoadjuvant CRT was only 43%,


a rate ascribed to significant fibrosis and inflammation caused by CRT (Isenberg et al., 1998). Consequently, EUS had a tendency to overstage lower pathological T stages. On the other hand, 79% of pathologically complete responders were diagnosed as having T+ disease (Zuccaro et al., 1999). These T+ patients underwent immediate post CRT surgery, but this could deem unnecessary because of pathological CR. Similarly, EUS could not detect microscopic disease, while 27% of patients with positive EUS findings proved to have no residual tumor in the resected specimens (Beseth et al., 2000). Furthermore, EUS may be suboptimal when the

Definitive Chemo-Radiotherapy for Resectable Esophageal Cancer — Unresolved Problems Remain

http://dx.doi.org/10.5772/55501

209

Researchers have reported a low accuracy of CT for the assessment of responses in patients with esophageal cancer; this accuracy was substantially worse than that of EUS and FDG-PET (fluorine18-labelled deoxyglucose in positron emission tomography). This is most likely owing to the difficulty in the differentiation between viable tumors and reactive changes, including edema, fibrosis, and inflammation at CT. CT tumor volume change was poorly correlated with pathological tumor response (Griffith et al., 1999). Some tumors exhibited marked volume regression with a poor histological response, while some tumors showed little volume regression with a considerable histological response. This means that CT by itself represents an inadequate tool in assessing those who have residual disease and those who should undergo

On the other hand, PET is a useful noninvasive tool in discriminating responders from nonresponders, with the colleration between PET-based response assessment and pathology being 78% (Flamen et al., 2002). The sensitivity and specificity of PET ranged from 71-100% and 55-95%, respectively (Brücher et al., 2001; Flamen et a., 2002; Weber et al., 2001). Any false positive results are attributable to the metabolically active leukocytes or macrophages associated with post CRT inflammation. False negative phenomena can occur because PET is

Patients who have received dCRT should undergo subsequent surgery if the tumors exhibit strictures or subsequent relapse. Salvage surgery is a surgery for residual or recurrent disease following dCRT, but it is technically more difficult and highly invasive than primary surgery, leading to increased morbidity (50-79%) and in-hospital mortality (7-22%) due to the adverse events of predominantly respiratory complications and anastomotic leakage (Chao et al., 2009; Nakamura et al., 2004; M. Nishimura et al., 2007; Oki et al., 2007; Smithers et al., 2007; Swisher et al., 2002; Tachimori et al., 2009; Tomimaru et al., 2006). These complications are attributable to the radiation-induced injury in the thoracic cavity that causes an increase in bleeding, fibrotic masses around the tumor due to the fibrogenic pathway that makes surgical technique more difficult, and an increasingly fragile stomach, esophagus, and trachea arising from the impaired blood supply that eventually causes anastomotic leakage or conduit necrosis. Even in Japan, these hospital mortality rates are obviously higher than those for primary esophagectomy reported from specialized centers or in a nationwide survey (2-4%) (Fujita et al., 2010; Suzuki et al., 2011; Tachimori et al., 2009). Reserving surgery for patients not already cured by CRT should always be taken into account in performing dCRT, and efforts

surgery following CRT. Jones et al. reported the same results (Jones, et al., 1999).

unable to detect perfectly the residual viable disease in the primary tumor.

sonography probe cannot pass the tumor.

**3.3. Salvage surgery is highly invasive**

SCC; squamous cell cancer. ADC; adenocarcinoma

ND; not described, CR; complete response

**Table 4.** Overall and local recurrence rates among CR patients undergoing dCRT.

**Figure 1.** Low and high magnifications of a patient who was considered CR after CRT. Histological specimens revealed small foci of a residual tumor in the esophageal wall which could not be detected by endoscopically obtained biopsy specimens preoperatively.

a rate ascribed to significant fibrosis and inflammation caused by CRT (Isenberg et al., 1998). Consequently, EUS had a tendency to overstage lower pathological T stages. On the other hand, 79% of pathologically complete responders were diagnosed as having T+ disease (Zuccaro et al., 1999). These T+ patients underwent immediate post CRT surgery, but this could deem unnecessary because of pathological CR. Similarly, EUS could not detect microscopic disease, while 27% of patients with positive EUS findings proved to have no residual tumor in the resected specimens (Beseth et al., 2000). Furthermore, EUS may be suboptimal when the sonography probe cannot pass the tumor.

Researchers have reported a low accuracy of CT for the assessment of responses in patients with esophageal cancer; this accuracy was substantially worse than that of EUS and FDG-PET (fluorine18-labelled deoxyglucose in positron emission tomography). This is most likely owing to the difficulty in the differentiation between viable tumors and reactive changes, including edema, fibrosis, and inflammation at CT. CT tumor volume change was poorly correlated with pathological tumor response (Griffith et al., 1999). Some tumors exhibited marked volume regression with a poor histological response, while some tumors showed little volume regression with a considerable histological response. This means that CT by itself represents an inadequate tool in assessing those who have residual disease and those who should undergo surgery following CRT. Jones et al. reported the same results (Jones, et al., 1999).

On the other hand, PET is a useful noninvasive tool in discriminating responders from nonresponders, with the colleration between PET-based response assessment and pathology being 78% (Flamen et al., 2002). The sensitivity and specificity of PET ranged from 71-100% and 55-95%, respectively (Brücher et al., 2001; Flamen et a., 2002; Weber et al., 2001). Any false positive results are attributable to the metabolically active leukocytes or macrophages associated with post CRT inflammation. False negative phenomena can occur because PET is unable to detect perfectly the residual viable disease in the primary tumor.

### **3.3. Salvage surgery is highly invasive**

**Author Tumor stage**

<sup>2006</sup> T1-4/N0-1/M0 50 Gy or 60

208 Cancer Treatment - Conventional and Innovative Approaches

SCC; squamous cell cancer. ADC; adenocarcinoma

**Table 4.** Overall and local recurrence rates among CR patients undergoing dCRT.

ND; not described, CR; complete response

specimens preoperatively.

Di Fiore,

Ishihara, 2010

Kumekaw

Minashi,

Morota, 2009

Murakami

Takeuchi, 2007

Tougeron , 2008

Wilson,

**Radiation**

**dose Histology Number of**

a, 2006 T1-4 and M1lymph 60 Gy SCC <sup>81</sup> 34(42.0%) ND 25%

<sup>2006</sup> T1N0M0 60 Gy SCC <sup>41</sup> 36(88%) 39% 14%

, 1998 0-III 60-75 Gy SCC <sup>30</sup> 16(53.3%) 19% ND

<sup>2000</sup> anyT, anyN, M0 50 Gy SCC+ADC <sup>31</sup> 24 (77.4%) 67% 21%

**Figure 1.** Low and high magnifications of a patient who was considered CR after CRT. Histological specimens revealed small foci of a residual tumor in the esophageal wall which could not be detected by endoscopically obtained biopsy

**patients**

I-IVA 60 Gy ND 173 110 (63.6%) 26% 12%

I-IVB 60 Gy SCC 69 36(52.2%) ND 17%

II-III 60 Gy SCC 178 113 (63.5%) 36% ND

I-IV 50-55 Gy SCC+ADC 109 63(58%) 52% 33%

**Complete responders (%)**

Gy SCC <sup>116</sup> 86 (74.1%) ND 40%

**Overall recurrence rate after CR**

**Local recurrence rate after CR**

> Patients who have received dCRT should undergo subsequent surgery if the tumors exhibit strictures or subsequent relapse. Salvage surgery is a surgery for residual or recurrent disease following dCRT, but it is technically more difficult and highly invasive than primary surgery, leading to increased morbidity (50-79%) and in-hospital mortality (7-22%) due to the adverse events of predominantly respiratory complications and anastomotic leakage (Chao et al., 2009; Nakamura et al., 2004; M. Nishimura et al., 2007; Oki et al., 2007; Smithers et al., 2007; Swisher et al., 2002; Tachimori et al., 2009; Tomimaru et al., 2006). These complications are attributable to the radiation-induced injury in the thoracic cavity that causes an increase in bleeding, fibrotic masses around the tumor due to the fibrogenic pathway that makes surgical technique more difficult, and an increasingly fragile stomach, esophagus, and trachea arising from the impaired blood supply that eventually causes anastomotic leakage or conduit necrosis. Even in Japan, these hospital mortality rates are obviously higher than those for primary esophagectomy reported from specialized centers or in a nationwide survey (2-4%) (Fujita et al., 2010; Suzuki et al., 2011; Tachimori et al., 2009). Reserving surgery for patients not already cured by CRT should always be taken into account in performing dCRT, and efforts

should be continuously made to reduce mortality and to select patients who stand to benefit most from this invasive treatment.

50.4Gy (Minsky et al., 2002; Nakajima et al., 2009) has recently prompted a phase II study of

Definitive Chemo-Radiotherapy for Resectable Esophageal Cancer — Unresolved Problems Remain

http://dx.doi.org/10.5772/55501

211

The combination of conventional CRT with molecular targeting therapies has been developing. This combination is encouraged by the findings that radiotherapy plus cetuximab, a mono‐ clonal antibody against epidermal growth factor receptor, for loco-regionally advanced SCC of the head and neck resulted in the prolonged duration of loco-regional control, progression free survival, and overall survival as compared with radiotherapy alone (Bonner et al., 2006; Bonner et al., 2010). The feasibility of adding cetuximab to CRT for esophageal cancer is supported by the safety profiles of this combination without any increase in esophagitis or other radiation-enhanced toxicity (Safran et al., 2008). The ongoing phase III trials (NCT 00655876, NCT01107639, NCT00509561) will provide evidence whether cetuximab in combi‐ nation with CRT is effective in locally advanced or resectable esophageal cancer (http://

A gain in survival with a substantial increase in toxicity necessitates considerable caution that immediately draws the attention of clinicians. Diagnostic tools which can accurately evaluate tumor response early in the course of dCRT can facilitate decisions about whether this toxic therapy should be continued in responders, or stopped in non-responders. However, there are currently no modalities that can definitively confirm CR. The reason for this problem is that the tools to estimate individual patient prognosis or tumor response are unreliable, and a diagnosis of CR is possibly merely by resected specimens. This means that negative findings by these imaging methods do not rule out residual disease. Clearly, patients with residual disease would no longer be long term survivors without undergoing resection. Therefore, efforts should continue to establish diagnostic tools for the detection of residual diseases after

One challenge in this regard lies in the detection of histologic markers—such as p53, Ki67, and EGF-R—for the prediction of therapeutic response; however, neither a single marker nor a combination of markers can correctly be used to predict the response with sufficient accuracy. The small number of patients or small number of genes investigated in this field is a further limitation. In the future, gene profiling may help identify markers that can be used in combi‐ nation with conventional imaging methods for the prediction of the response to dCRT.

dCRT with a radiation dose of 50.4Gy for stage II/III esophageal SCC (JCOG0909).

**4. Future perspectives**

clinicaltrials.gov).

CRT.

**Author details**

Shouji Shimoyama

Gastrointestinal Unit, Settlement Clinic, Japan

First, invasiveness undoubtedly depends on surgical procedure. The most common surgical approaches which are applicable to cancers of the upper, middle and lower esophagus are the Ivor-Lewis or McKeown esophagectomy. The Ivor-Lewis esophagectomy involves right thoracotomy with midline laparotomy and an anastomosis of the gastric conduit to the proximal mediastinal esophagus (at or above the azygos vein). The McKeown technique involves right thoracotomy, laparotomy, and cervical anastomosis, which facilitates precise surgical staging and enables more local control (van de Ven et al., 1999). The extent of lym‐ phadenectomy is three-field (cervial thoracic, abdominal), which has traditionally been more prevalent in Japan, measuring the prevalence of positive cervical nodes (Akiyama et al., 1994; Nishihira et al., 1995). The survival benefit of three-field lymphadenectomy was suggeted in Japanese (Nishihira et al., 1998) and Western series (Altorki et al., 2002). Importantly, the risks of positive cervical nodes are substantial even at an earlier stage (Stein et al., 2005), and are seemingly independent of histological types (SCC or adenocarcinoma) or independent of tumor location within the esophagus (Akiyama et al., 1994; van de Ven et al., 1999). The McKeown technique enables this dissection to be performed under direct vision, allowing more precise dissection in cases where the tumor is large, lymphadenopathy is present, or the tumor is located in proximity to the airway (upper or middle thoracic esophagus). However, in salvage surgery, attempts have been made to reduce surgical morbidity and mortality with preservation of the blood supply to the trachea or to the main bronchus as well as to the reconstruction conduit. These include a reduced scope of lymphadenectomy with avoidance of cervical lymph node dissection or the preservation of right and left bronchial arteries (Tachimori et al., 2009).

Second, an accurate prediction of resection status prior to surgery is important at the time of completion of dCRT since resection status is one of the significant factors that affect survival after salvage surgery. Long term survivors after salvage surgery were those undergoing R0 resection, while no patients left with gross or microscopic residual tumors after salvage surgery (R1/R2 resections) survived more than 24 months in any series (Chao et al., 2009; Nakamura et al., 2004; Oki et al., 2007; Swisher et al., 2002; Tachimori et al., 2009; Tomimaru et al., 2006). Multivariate analysis also confirmed resection status correlation with patient survival (Chao et al., 2009; Tomimaru et al., 2006). However, the resection status cannot be confidently predicted before surgery or even during surgery because of the indistinct planes between a tumor and fibrotic masses within the irradiated mediastinum. In this regard, PET, which has a relatively high specificity, could identify non-responders for dCRT and may be a more useful imaging modality than CT or EUS (Swisher et al., 2004) to select patients who are absolutely unfit for salvage surgery, allowing for early modifications of the treatment strategy of such selected patients.

Third, it is imaginable that larger, more advanced cancers are more difficult to control than smaller ones and require longer doses of RT; however, higher radiation doses are associated with increased morbidity. A dose of 60Gy of radiation has been used for dCRT in Japan (Kenjo et al., 2009). In this regard, the possibility of reducing total radiation volume from 64.8Gy to 50.4Gy (Minsky et al., 2002; Nakajima et al., 2009) has recently prompted a phase II study of dCRT with a radiation dose of 50.4Gy for stage II/III esophageal SCC (JCOG0909).

### **4. Future perspectives**

should be continuously made to reduce mortality and to select patients who stand to benefit

First, invasiveness undoubtedly depends on surgical procedure. The most common surgical approaches which are applicable to cancers of the upper, middle and lower esophagus are the Ivor-Lewis or McKeown esophagectomy. The Ivor-Lewis esophagectomy involves right thoracotomy with midline laparotomy and an anastomosis of the gastric conduit to the proximal mediastinal esophagus (at or above the azygos vein). The McKeown technique involves right thoracotomy, laparotomy, and cervical anastomosis, which facilitates precise surgical staging and enables more local control (van de Ven et al., 1999). The extent of lym‐ phadenectomy is three-field (cervial thoracic, abdominal), which has traditionally been more prevalent in Japan, measuring the prevalence of positive cervical nodes (Akiyama et al., 1994; Nishihira et al., 1995). The survival benefit of three-field lymphadenectomy was suggeted in Japanese (Nishihira et al., 1998) and Western series (Altorki et al., 2002). Importantly, the risks of positive cervical nodes are substantial even at an earlier stage (Stein et al., 2005), and are seemingly independent of histological types (SCC or adenocarcinoma) or independent of tumor location within the esophagus (Akiyama et al., 1994; van de Ven et al., 1999). The McKeown technique enables this dissection to be performed under direct vision, allowing more precise dissection in cases where the tumor is large, lymphadenopathy is present, or the tumor is located in proximity to the airway (upper or middle thoracic esophagus). However, in salvage surgery, attempts have been made to reduce surgical morbidity and mortality with preservation of the blood supply to the trachea or to the main bronchus as well as to the reconstruction conduit. These include a reduced scope of lymphadenectomy with avoidance of cervical lymph node dissection or the preservation of right and left bronchial arteries

Second, an accurate prediction of resection status prior to surgery is important at the time of completion of dCRT since resection status is one of the significant factors that affect survival after salvage surgery. Long term survivors after salvage surgery were those undergoing R0 resection, while no patients left with gross or microscopic residual tumors after salvage surgery (R1/R2 resections) survived more than 24 months in any series (Chao et al., 2009; Nakamura et al., 2004; Oki et al., 2007; Swisher et al., 2002; Tachimori et al., 2009; Tomimaru et al., 2006). Multivariate analysis also confirmed resection status correlation with patient survival (Chao et al., 2009; Tomimaru et al., 2006). However, the resection status cannot be confidently predicted before surgery or even during surgery because of the indistinct planes between a tumor and fibrotic masses within the irradiated mediastinum. In this regard, PET, which has a relatively high specificity, could identify non-responders for dCRT and may be a more useful imaging modality than CT or EUS (Swisher et al., 2004) to select patients who are absolutely unfit for salvage surgery, allowing for early modifications of the treatment strategy of such

Third, it is imaginable that larger, more advanced cancers are more difficult to control than smaller ones and require longer doses of RT; however, higher radiation doses are associated with increased morbidity. A dose of 60Gy of radiation has been used for dCRT in Japan (Kenjo et al., 2009). In this regard, the possibility of reducing total radiation volume from 64.8Gy to

most from this invasive treatment.

210 Cancer Treatment - Conventional and Innovative Approaches

(Tachimori et al., 2009).

selected patients.

The combination of conventional CRT with molecular targeting therapies has been developing. This combination is encouraged by the findings that radiotherapy plus cetuximab, a mono‐ clonal antibody against epidermal growth factor receptor, for loco-regionally advanced SCC of the head and neck resulted in the prolonged duration of loco-regional control, progression free survival, and overall survival as compared with radiotherapy alone (Bonner et al., 2006; Bonner et al., 2010). The feasibility of adding cetuximab to CRT for esophageal cancer is supported by the safety profiles of this combination without any increase in esophagitis or other radiation-enhanced toxicity (Safran et al., 2008). The ongoing phase III trials (NCT 00655876, NCT01107639, NCT00509561) will provide evidence whether cetuximab in combi‐ nation with CRT is effective in locally advanced or resectable esophageal cancer (http:// clinicaltrials.gov).

A gain in survival with a substantial increase in toxicity necessitates considerable caution that immediately draws the attention of clinicians. Diagnostic tools which can accurately evaluate tumor response early in the course of dCRT can facilitate decisions about whether this toxic therapy should be continued in responders, or stopped in non-responders. However, there are currently no modalities that can definitively confirm CR. The reason for this problem is that the tools to estimate individual patient prognosis or tumor response are unreliable, and a diagnosis of CR is possibly merely by resected specimens. This means that negative findings by these imaging methods do not rule out residual disease. Clearly, patients with residual disease would no longer be long term survivors without undergoing resection. Therefore, efforts should continue to establish diagnostic tools for the detection of residual diseases after CRT.

One challenge in this regard lies in the detection of histologic markers—such as p53, Ki67, and EGF-R—for the prediction of therapeutic response; however, neither a single marker nor a combination of markers can correctly be used to predict the response with sufficient accuracy. The small number of patients or small number of genes investigated in this field is a further limitation. In the future, gene profiling may help identify markers that can be used in combi‐ nation with conventional imaging methods for the prediction of the response to dCRT.

### **Author details**

Shouji Shimoyama

Gastrointestinal Unit, Settlement Clinic, Japan

### **References**

[1] Akiyama, H, Tsurumaru, M, Udagawa, H, & Kajiyama, Y. (1994). Radical lymph node dissection for cancer of the thoracic esophagus. Ann Surg. , 220(3)

[12] Bonner, J. A, Harari, P. M, Giralt, J, Cohen, R. B, Jones, C. U, Sur, R. K, Raben, D, Baselga, J, Spencer, S. A, Zhu, J, Youssoufian, H, Rowinsky, E. K, & Ang, K. K. (2010). Radiotherapy plus cetuximab for locoregionally advanced head and neck cancer: 5 year survival data from a phase 3 randomised trial, and relation between cetuximab-

Definitive Chemo-Radiotherapy for Resectable Esophageal Cancer — Unresolved Problems Remain

http://dx.doi.org/10.5772/55501

213

[13] Brücher, B. L, Weber, W, Bauer, M, Fink, U, Avril, N, Stein, H. J, Werner, M, Zimmer‐ man, F, Siewert, J. R, & Schwaiger, M. (2001). Neoadjuvant therapy of esophageal squamous cell carcinoma: response evaluation by positron emission tomography.

[14] Chao, Y. K, Chan, S. C, Chang, H. K, Liu, Y. H, Wu, Y. C, Hsieh, M. J, Tseng, C. K, & Liu, H. P. (2009). Salvage surgery after failed chemo-radiotherapy in squamous cell

[15] Chiu, P. W, Chan, A. C, Leung, S. F, Leong, H. T, Kwong, K. H, Li, M. K, Au-yeung, A. C, Chung, S. C, & Ng, E. K. (2005). Multicenter prospective randomized trial com‐ paring standard esophagectomy with chemo-radiotherapy for treatment of squa‐ mous esophageal cancer: early results from the Chinese University Research Group

[17] Cosset, J. M, Henry-amar, M, Pellae-cosset, B, Carde, P, Girinski, T, Tubiana, M, & Hayat, M. (1991). Pericarditis and myocardial infarctions after Hodgkin's disease

[18] Daly, J. M, Karnell, L. H, & Menck, H. R. (1996). National Cancer Data Base report on

[19] Di FioreF., Lecleire, S., Rigal, O., Galais, M.P., Ben Soussan, E., David, I., Paillot, B., Jacob, J.H., & Michel, P. ((2006). Predictive factors of survival in patients treated with definitive chemo-radiotherapy for squamous cell esophageal carcinoma. World J

[20] Dimick, J. B, Wainess, R. M, & Upchurch, G. R. Jr, Iannettoni, M.D., & Orringer, M.B. ((2005). National trends in outcomes for esophageal resection. Ann Thorac Surg. ,

[21] Finks, J. F, Osborne, N. H, & Birkmeyer, J. D. (2011). Trends in hospital volume and operative mortality for high-risk surgery. N Engl J Med. , 364(22), 2128-2137.

[22] Fiorica, F. Di Bona, D., Schepis, F., Licata, A., Shahied, L., Venturi, A., Falchi, A.M., Craxì, A., & Cammà, C. ((2004). Preoperative chemo-radiotherapy for oesophageal

[23] Flamen, P, Van Cutsem, E, Lerut, A, Cambier, J. P, Haustermans, K, Bormans, G, De Leyn, P, Van Raemdonck, D, De Wever, W, Ectors, N, Maes, A, & Mortelmans, L. (2002). Positron emission tomography for assessment of the response to induction ra‐

cancer: a systematic review and meta-analysis. Gut. , 53(7), 925-930.

induced rash and survival. Lancet Oncol. , 11(1), 21-28.

carcinoma of the esophagus. Eur J Surg Oncol. , 35(3), 289-294.

for Esophageal Cancer (CURE). J Gastrointest Surg. , 9(6), 794-802.

therapy. Int J Radiat Oncol Biol Phys. , 21(2), 447-449.

esophageal carcinoma. Cancer. , 78(8), 1820-1828.

Gastroenterol. , 12(26), 4185-4190.

Ann Surg. , 233(3), 300-309.

[16] http://clinicaltrialsgov

79(1), 212-216.


**References**

212 Cancer Treatment - Conventional and Innovative Approaches

[1] Akiyama, H, Tsurumaru, M, Udagawa, H, & Kajiyama, Y. (1994). Radical lymph

[2] Allen, A. M, & Henning, G. T. Ten Haken, R.K., Hayman, J.A., & Martel, M.K. ((2003). Do dose-volume metrics predict pulmonary function changes in lung irradia‐

[3] Altorki, N, Kent, M, Ferrara, C, & Port, J. (2002). Three-field lymph node dissection for squamous cell and adenocarcinoma of the esophagus. Ann Surg. , 236(2)

[4] Ariga, H, Nemoto, K, Miyazaki, S, Yoshioka, T, Ogawa, Y, Sakayauchi, T, Jingu, K, Miyata, G, Onodera, K, Ichikawa, H, Kamei, T, Kato, S, Ishioka, C, Satomi, S, & Ya‐ mada, S. (2009). Prospective comparison of surgery alone and chemo-radiotherapy with selective surgery in resectable squamous cell carcinoma of the esophagus. Int J

[5] Atkins, B. Z, Shah, A. S, Hutcheson, K. A, Mangum, J. H, Pappas, T. N, & Harpole, D. H. Jr, & D'Amico, T.A. ((2004). Reducing hospital morbidity and mortality following

[6] Bailey, S. H, Bull, D. A, Harpole, D. H, Rentz, J. J, Neumayer, L. A, Pappas, T. N, Da‐ ley, J, Henderson, W. G, Krasnicka, B, & Khuri, S. F. (2003). Outcomes after esopha‐

[7] Bedenne, L, Michel, P, Bouché, O, Milan, C, Mariette, C, Conroy, T, Pezet, D, Roullet, B, Seitz, J. F, Herr, J. P, Paillot, B, Arveux, P, Bonnetain, F, & Binquet, C. (2007). Che‐ moradiation followed by surgery compared with chemoradiation alone in squamous

[8] Beseth, B. D, Bedford, R, Isacoff, W. H, Holmes, E. C, & Cameron, R. B. (2000). Endo‐ scopic ultrasound does not accurately assess pathologic stage of esophageal cancer

[9] Birkmeyer, J. D, Siewers, A. E, Finlayson, E. V, Stukel, T. A, Lucas, F. L, Batista, I, Welch, H. G, & Wennberg, D. E. (2002). Hospital volume and surgical mortality in

[10] Blazeby, J. M, Farndon, J. R, Donovan, J, & Alderson, D. (2000). A prospective longi‐ tudinal study examining the quality of life of patients with esophageal carcinoma.

[11] Bonner, J. A, Harari, P. M, Giralt, J, Azarnia, N, Shin, D. M, Cohen, R. B, Jones, C. U, Sur, R, Raben, D, Jassem, J, Ove, R, Kies, M. S, Baselga, J, Youssoufian, H, Amellal, N, Rowinsky, E. K, & Ang, K. K. (2006). Radiotherapy plus cetuximab for squamous-cell

gectomy: a ten-year prospective cohort. Ann Thorac Surg. , 75(1), 217-222.

cancer of the esophagus: FFCD 9102. J Clin Oncol. , 25(10), 1160-1168.

after neoadjuvant chemo-radiotherapy. Am Surg. , 66(9), 827-831.

carcinoma of the head and neck. N Engl J Med. , 354(6), 567-578.

the United States. N Engl J Med. , 346(15), 1128-1137.

Cancer. , 88(8), 1781-1787.

node dissection for cancer of the thoracic esophagus. Ann Surg. , 220(3)

tion? Int J Radiat Oncol Biol Phys. , 55(4), 921-929.

esophagectomy. Ann Thorac Surg. , 78(4), 1170-1176.

Radiat Oncol Biol Phys. , 75(2), 348-356.


diochemotherapy in locally advanced oesophageal cancer. Ann Oncol. , 13(3), 361-368.

[35] Japanese Society of Esophageal diseasesComprehensive registry of esophageal can‐

Definitive Chemo-Radiotherapy for Resectable Esophageal Cancer — Unresolved Problems Remain

http://dx.doi.org/10.5772/55501

215

[36] Jemal, A, Center, M. M, Desantis, C, & Ward, E. M. (2010). Global patterns of cancer incidence and mortality rates and trends. Cancer Epidemiol Biomarkers Prev. , 19(8),

[37] Jones, D. R, Detterbeck, F. C, Egan, T. M, & Parker, L. A. Jr, Bernard, S.A., & Tepper, J.E. ((1997). Induction chemo-radiotherapy followed by esophagectomy in patients

[38] Jones, D. R, & Parker, L. A. Jr, Detterbeck, F.C., & Egan, T.M. ((1999). Inadequacy of computed tomography in assessing patients with esophageal carcinoma after induc‐

[39] Kato, H, Sato, A, Fukuda, H, Kagami, Y, Udagawa, H, Togo, A, Ando, N, Tanaka, O, Shinoda, M, Yamana, H, & Ishikura, S. II trial of chemo-radiotherapy for stage I esophageal squamous cell carcinoma: Japan Clinical Oncology Group Study

[40] Kato, K, Muro, K, Minashi, K, Ohtsu, A, Ishikura, S, Boku, N, Takiuchi, H, Komatsu, Y, Miyata, Y, & Fukuda, H. Gastrointestinal Oncology Study Group of the Japan Clinical Oncology Group (JCOG). ((2011). Phase II Study of Chemo-radiotherapy with 5-Fluorouracil and Cisplatin for Stage II-III Esophageal Squamous Cell Carcino‐

[41] Kazui, T, Osada, H, & Fujita, H. Committee for Scientific Affairs. ((2007). An attempt to analyze the relation between hospital surgical volume and clinical outcome. Gen

[42] Keighley, M. R. (2003). Gastrointestinal cancers in Europe. Aliment Pharmacol Ther.

[43] Kenjo, M, Uno, T, Murakami, Y, Nagata, Y, Oguchi, M, Saito, S, Numasaki, H, Teshi‐ ma, T, & Mitsumori, M. (2009). Radiation therapy for esophageal cancer in Japan: re‐ sults of the Patterns of Care Study 1999-2001. Int J Radiat Oncol Biol Phys. , 75(2),

[44] Kleinberg, L, Gibson, M, Forastiere, K, & Chemo-radiotherapy, A. A. for localized esophageal cancer: regimen selection and molecular mechanisms of radiosensitiza‐

[45] Kranzfelder, M, Schuster, T, Geinitz, H, Friess, H, & Büchler, P. (2011). Meta-analysis of neoadjuvant treatment modalities and definitive non-surgical therapy for oeso‐

[46] Kumekawa, Y, Kaneko, K, Ito, H, Kurahashi, T, Konishi, K, Katagiri, A, Yamamoto, T, Kuwahara, M, Kubota, Y, Muramoto, T, Mizutani, Y, & Imawari, M. (2006). Late

ma: JCOG Trial (JCOG 9906). Int J Radiat Oncol Biol Phys. , 81(3), 684-690.

with carcinoma of the esophagus. Ann Thorac Surg. , 64(1), 185-191.

cer in Japan, 1999. ((2005). Esophagus, , 2(2), 43-69.

tion chemo-radiotherapy. Cancer. , 85(5)

(JCOG9708). Jpn J Clin Oncol. , 39(10), 638-643.

Thorac Cardiovasc Surg. , 55(12), 483-492.

tion. Nat Clin Pract Oncol. , 4(5), 282-294.

phageal squamous cell cancer. Br J Surg. , 98(6), 768-783.

Suppl 3, , 18, 7-30.

357-363.

1893-1907.


[35] Japanese Society of Esophageal diseasesComprehensive registry of esophageal can‐ cer in Japan, 1999. ((2005). Esophagus, , 2(2), 43-69.

diochemotherapy in locally advanced oesophageal cancer. Ann Oncol. , 13(3),

[24] Fujita, H, Ozawa, S, Kuwano, H, Ueda, Y, Hattori, S, & Yanagawa, T. (2010). Esopha‐ gectomy for cancer: clinical concerns support centralizing operations within the larg‐

[26] Griffith, J. F, Chan, A. C, Chow, L. T, Leung, S. F, Lam, Y. H, Liang, E. Y, Chung, S. C, & Metreweli, C. (1999). Assessing chemotherapy response of squamous cell oesopha‐

[27] Hernando, M. L, Marks, L. B, Bentel, G. C, Zhou, S. M, Hollis, D, Das, S. K, Fan, M, Munley, M. T, Shafman, T. D, Anscher, M. S, & Lind, P. A. (2001). Radiation-induced pulmonary toxicity: a dose-volume histogram analysis in 201 patients with lung can‐

[28] Hirata, N, Kawamoto, K, Ueyama, T, Masuda, K, Utsunomiya, T, & Kuwano, H. (1997). Using endosonography to assess the effects of neoadjuvant therapy in pa‐ tients with advanced esophageal cancer. AJR Am J Roentgenol. , 169(2), 485-491.

[29] Hironaka, S, Ohtsu, A, Boku, N, Muto, M, Nagashima, F, Saito, H, Yoshida, S, Nishi‐ mura, M, Haruno, M, Ishikura, S, Ogino, T, Yamamoto, S, & Ochiai, A. (2003). Non‐ randomized comparison between definitive chemo-radiotherapy and radical surgery in patients with T(2-3)N(any) M(0) squamous cell carcinoma of the esophagus. Int J

[31] Isenberg, G, Chak, A, Canto, M. I, Levitan, N, Clayman, J, Pollack, B. J, & Sivak, M. V. Jr. ((1998). Endoscopic ultrasound in restaging of esophageal cancer after neoadju‐

[32] Ishida, K, Ando, N, Yamamoto, S, Ide, H, & Shinoda, M. (2004). Phase II study of cis‐ platin and 5-fluorouracil with concurrent radiotherapy in advanced squamous cell carcinoma of the esophagus: a Japan Esophageal Oncology Group (JEOG)/Japan

Clinical Oncology Group trial (JCOG9516). Jpn J Clin Oncol. , 34(10), 615-619.

[33] Ishihara, R, Yamamoto, S, Iishi, H, Takeuchi, Y, Sugimoto, N, Higashino, K, Uedo, N, Tatsuta, M, Yano, M, Imai, A, & Nishiyama, K. (2010). Factors predictive of tumor re‐ currence and survival after initial complete response of esophageal squamous cell carcinoma to definitive chemo-radiotherapy. Int J Radiat Oncol Biol Phys. , 76(1),

[34] Ishikura, S, Nihei, K, Ohtsu, A, Boku, N, Hironaka, S, Mera, K, Muto, M, Ogino, T, & Yoshida, S. (2003). Long-term toxicity after definitive chemo-radiotherapy for squa‐ mous cell carcinoma of the thoracic esophagus. J Clin Oncol. , 21(14), 2697-2702.

[30] http://infocancerresearchuk.org/cancerstats/types/oesophagus/survival/

vant chemoradiation. Gastrointest Endosc. , 48(2), 158-163.

er hospitals. Dis Esophagus. , 23(2), 145-152.

cer. Int J Radiat Oncol Biol Phys. , 51(3), 650-659.

Radiat Oncol Biol Phys. , 57(2), 425-433.

[25] http://ganjohojp/public/statistics/backnumber/(2011). en.html

geal carcinoma with spiral CT. Br J Radiol. , 72(859), 678-684.

361-368.

214 Cancer Treatment - Conventional and Innovative Approaches

123-129.


toxicity in complete response cases after definitive chemo-radiotherapy for esopha‐ geal squamous cell carcinoma. J Gastroenterol. , 41(5), 425-432.

[58] Morota, M, Gomi, K, Kozuka, T, Chin, K, Matsuura, M, Oguchi, M, Ito, H, & Yama‐ shita, T. (2009). Late toxicity after definitive concurrent chemo-radiotherapy for

Definitive Chemo-Radiotherapy for Resectable Esophageal Cancer — Unresolved Problems Remain

http://dx.doi.org/10.5772/55501

217

[59] Murakami, M, Kuroda, Y, Okamoto, Y, Kono, K, Yoden, E, Kusumi, F, Hajiro, K, Matsusue, S, & Takeda, H. (1998). Neoadjuvant concurrent chemo-radiotherapy fol‐ lowed by definitive high-dose radiotherapy or surgery for operable thoracic esopha‐

[60] Nakajima, T. E, Ura, T, Ito, Y, Kato, K, Minashi, K, Nihei, K, Hironaka, S, Boku, N, Kagami, Y, & Muro, K. I trial of 5-fluorouracil with cisplatin and concurrent stand‐ ard-dose radiotherapy in Japanese patients with stage II/III esophageal cancer. Jpn J

[61] Nakamura, T, Hayashi, K, Ota, M, Eguchi, R, Ide, H, Takasaki, K, & Mitsuhashi, N. (2004). Salvage esophagectomy after definitive chemotherapy and radiotherapy for

[62] Nishihira, T, Hirayama, K, & Mori, S. (1998). A prospective randomized trial of ex‐ tended cervical and superior mediastinal lymphadenectomy for carcinoma of the

[63] Nishihira, T, Sayama, J, Ueda, H, Sugawara, K, Takano, R, Sagawa, J, Katayama, M, Shineha, R, Hirayama, K, & Mori, S. (1995). Lymph flow and lymph node metastasis

[64] Nishimura, M, Daiko, H, Yoshida, J, & Nagai, K. (2007). Salvage esophagectomy fol‐ lowing definitive chemo-radiotherapy. Gen Thorac Cardiovasc Surg. , 55(11),

[65] Nishimura, Y, Suzuki, M, Nakamatsu, K, Kanamori, S, Yagyu, Y, & Shigeoka, H. (2002). Prospective trial of concurrent chemo-radiotherapy with protracted infusion of 5-fluorouracil and cisplatin for T4 esophageal cancer with or without fistula. Int J

[66] Ohtsu, A, Boku, N, Muro, K, Chin, K, Muto, M, Yoshida, S, Satake, M, Ishikura, S, Ogino, T, Miyata, Y, Seki, S, Kaneko, K, & Nakamura, A. (1999). Definitive chemoradiotherapy for T4 and/or M1 lymph node squamous cell carcinoma of the esopha‐

[67] Oki, E, Morita, M, Kakeji, Y, Ikebe, M, Sadanaga, N, Egasira, A, Nishida, K, Koga, T, Ohata, M, Honboh, T, Yamamoto, M, Baba, H, & Maehara, Y. (2007). Salvage esopha‐ gectomy after definitive chemo-radiotherapy for esophageal cancer. Dis Esophagus. ,

[68] Orringer, M. B, Marshall, B, Chang, A. C, Lee, J, & Pickens, A. Two thousand tran‐ shiatal esophagectomies: changing trends, lessons learned. Ann Surg. , 246(3),

thoracic esophageal carcinoma. Int J Radiat Oncol Biol Phys. , 75(1), 122-128.

geal carcinoma. Int J Radiat Oncol Biol Phys. , 40(5), 1049-1059.

advanced esophageal cancer. Am J Surg. , 188(3), 261-266.

Clin Oncol. , 39(1), 37-42.

461-464.

20(4), 301-304.

363-372.

thoracic esophagus. Am J Surg. , 175(1)

in esophageal cancer. Surg Today. , 25(4)

Radiat Oncol Biol Phys. , 53(1), 134-139.

gus. J Clin Oncol. , 17(9), 2915-2921.


[58] Morota, M, Gomi, K, Kozuka, T, Chin, K, Matsuura, M, Oguchi, M, Ito, H, & Yama‐ shita, T. (2009). Late toxicity after definitive concurrent chemo-radiotherapy for thoracic esophageal carcinoma. Int J Radiat Oncol Biol Phys. , 75(1), 122-128.

toxicity in complete response cases after definitive chemo-radiotherapy for esopha‐

[47] Li, Q. Q, Liu, M. Z, Hu, Y. H, Liu, H, He, Z. Y, & Lin, H. X. (2010). Definitive concom‐ itant chemo-radiotherapy with docetaxel and cisplatin in squamous esophageal car‐

[48] Lim, J. T, Truong, P. T, Berthelet, E, Pai, H, Joe, H, Wai, E, Larsson, S, Kader, H. A, Weinerman, B, Wilson, K, & Olivotto, I. A. (2003). Endoscopic response predicts for survival and organ preservation after primary chemo-radiotherapy for esophageal

[49] Lin, H. C, Xirasagar, S, Lee, H. C, & Chai, C. Y. (2006). Hospital volume and inpatient mortality after cancer-related gastrointestinal resections: the experience of an Asian

[50] Madani, I, De Ruyck, K, Goeminne, H, De Neve, W, Thierens, H, & Van Meerbeeck, J. (2007). Predicting risk of radiation-induced lung injury. J Thorac Oncol. , 2(9),

[51] Martel, M. K, & Sahijdak, W. M. Ten Haken, R.K., Kessler, M.L., & Turrisi, A.T.

[52] Fraction size and dose parameters related to the incidence of pericardial effusionsInt

[53] Mcdonald, S, Rubin, P, Phillips, T. L, & Marks, L. B. (1995). Injury to the lung from cancer therapy: clinical syndromes, measurable endpoints, and potential scoring sys‐

[54] Metzger, R, Bollschweiler, E, Vallböhmer, D, Maish, M, Demeester, T. R, & Hölscher, A. H. (2004). High volume centers for esophagectomy: what is the number needed to

[55] Migliore, M, Choong, C. K, Lim, E, Goldsmith, K. A, Ritchie, A, & Wells, F. C. s case volume of oesophagectomy for cancer strongly influences the operative mortality

[56] Minashi, K, Doi, T, Muto, M, Mera, K, Yano, T, & Ohtsu, A. (2006). chemo-radiother‐ apy for superficial esophageal squamous cell carcinoma. Stomach and Intestine. , 41,

[57] Minsky, B. D, Pajak, T. F, Ginsberg, R. J, Pisansky, T. M, Martenson, J, Komaki, R, Okawara, G, Rosenthal, S. A, & Kelsen, D. P. (2002). INT 0123 (Radiation Therapy Oncology Group 94-05) phase III trial of combined-modality therapy for esophageal cancer: high-dose versus standard-dose radiation therapy. J Clin Oncol. , 20(5),

achieve low postoperative mortality? Dis Esophagus. , 17(4), 310-314.

geal squamous cell carcinoma. J Gastroenterol. , 41(5), 425-432.

cancer. Int J Radiat Oncol Biol Phys. , 57(5), 1328-1335.

cinoma. Dis Esophagus. , 23(3), 253-259.

216 Cancer Treatment - Conventional and Innovative Approaches

country. Ann Surg Oncol. , 13(9), 1182-1188.

J Radiat Oncol Biol Phys. , 40(1), 155-161.

tems. Int J Radiat Oncol Biol Phys. , 31(5), 1187-1203.

rate. Eur J Cardiothorac Surg. , 32(2), 375-380.

864-874.

((1998).

1467-1474.

1167-1174.


[69] Pöttgen, C, & Stuschke, M. (2012). Radiotherapy versus surgery within multimodali‐ ty protocols for esophageal cancer- A meta-analysis of the randomized trials. Cancer Treat Rev. , 38(6), 599-604.

Chemoradiation with and without surgery in patients with locally advanced squa‐

Definitive Chemo-Radiotherapy for Resectable Esophageal Cancer — Unresolved Problems Remain

http://dx.doi.org/10.5772/55501

219

[79] Stein, H. J, Feith, M, Bruecher, B. L, Naehrig, J, Sarbia, M, & Siewert, J. R. (2005). Ear‐ ly esophageal cancer: pattern of lymphatic spread and prognostic factors for long-

[80] Steyerberg, E. W, Neville, B. A, Koppert, L. B, Lemmens, V. E, Tilanus, H, Coebergh, W, Weeks, J. W, & Earle, J. C. C.C. ((2006). Surgical mortality in patients with esopha‐ geal cancer: development and validation of a simple risk score. J Clin Oncol. , 24(26),

[81] Suzuki, H, Gotoh, M, Sugihara, K, Kitagawa, Y, Kimura, W, Kondo, S, Shimada, M, Tomita, N, Nakagoe, T, Hashimoto, H, Baba, H, Miyata, H, & Motomura, N. (2011). Nationwide survey and establishment of a clinical database for gastrointestinal sur‐ gery in Japan: Targeting integration of a cancer registration system and improving

[82] Swisher, S. G, Maish, M, Erasmus, J. J, Correa, A. M, Ajani, J. A, Bresalier, R, Komaki, R, Macapinlac, H, Munden, R. F, Putnam, J. B, Rice, D, Smythe, W. R, Vaporciyan, A. A, Walsh, G. L, Wu, T. T, & Roth, J. A. (2004). Utility of PET, CT, and EUS to identify pathologic responders in esophageal cancer. Ann Thorac Surg. , 78(4), 1152-1160. [83] Swisher, S. G, Wynn, P, Putnam, J. B, Mosheim, M. B, Correa, A. M, Komaki, R. R, Ajani, J. A, Smythe, W. R, Vaporciyan, A. A, Roth, J. A, & Walsh, G. L. (2002). Salvage esophagectomy for recurrent tumors after definitive chemotherapy and radiothera‐

[84] Tachimori, Y, Kanamori, N, Uemura, N, Hokamura, N, Igaki, H, & Kato, H. (2009). Salvage esophagectomy after high-dose chemo-radiotherapy for esophageal squa‐

[85] Takeuchi, S, Ohtsu, A, Doi, T, Kojima, T, Minashi, K, Mera, K, Yano, T, Tahara, M, Muto, M, & Nihei, K. (2007). A retrospective study of definitive chemo-radiotherapy

[86] Tomimaru, Y, Yano, M, Takachi, K, Miyashiro, I, Ishihara, R, Nishiyama, K, Sasaki, Y, Ishikawa, O, Doki, Y, & Imaoka, S. (2006). Factors affecting the prognosis of pa‐ tients with esophageal cancer undergoing salvage surgery after definitive chemo-ra‐

[87] Tougeron, D. Di Fiore, F., Thureau, S., Berbera, N., Iwanicki-Caron, I., Hamidou, H., Paillot, B., & Michel, P. ((2008). Safety and outcome of definitive chemo-radiotherapy

[88] Tsujino, K, Hirota, S, Endo, M, Obayashi, K, Kotani, Y, Satouchi, M, Kado, T, & Taka‐ da, Y. (2003). Predictive value of dose-volume histogram parameters for predicting

in elderly patients with oesophageal cancer. Br J Cancer. , 99(10), 1586-1592.

for elderly patients with esophageal cancer. Am J Clin Oncol. , 30(6), 607-611.

mous cell carcinoma of the esophagus. J Clin Oncol. , 23(10), 2310-2317.

term survival after surgical resection. Ann Surg. , 242(4)

the outcome of cancer treatment. Cancer Sci. , 102(1), 226-230.

mous cell carcinoma. J Thorac Cardiovasc Surg. , 137(1), 49-54.

py. J Thorac Cardiovasc Surg. , 123(1), 175-183.

diotherapy. J Surg Oncol. , 93(5), 422-428.

4277-4284.


Chemoradiation with and without surgery in patients with locally advanced squa‐ mous cell carcinoma of the esophagus. J Clin Oncol. , 23(10), 2310-2317.

[79] Stein, H. J, Feith, M, Bruecher, B. L, Naehrig, J, Sarbia, M, & Siewert, J. R. (2005). Ear‐ ly esophageal cancer: pattern of lymphatic spread and prognostic factors for longterm survival after surgical resection. Ann Surg. , 242(4)

[69] Pöttgen, C, & Stuschke, M. (2012). Radiotherapy versus surgery within multimodali‐ ty protocols for esophageal cancer- A meta-analysis of the randomized trials. Cancer

[70] Rentz, J, Bull, D, Harpole, D, Bailey, S, Neumayer, L, Pappas, T, Krasnicka, B, Hen‐ derson, W, Daley, J, & Khuri, S. (2003). Transthoracic versus transhiatal esophagecto‐ my: a prospective study of 945 patients. J Thorac Cardiovasc Surg. , 125(5), 1114-1120.

[71] Rice, T. W, Rusch, V. W, Apperson-hansen, C, Allen, M. S, Chen, L. Q, Hunter, J. G, Kesler, K. A, Law, S, Lerut, T. E, Reed, C. E, Salo, J. A, Scott, W. J, Swisher, S. G, Wat‐ son, T. J, & Blackstone, E. H. Worldwide esophageal cancer collaboration. ((2009). Dis

[72] Roach, M. rd,. Gandara, D.R., You, H.S., Swift, P.S., Kroll, S., Shrieve, D.C., Wara, W.M., Margolis, L., & Phillips, T.L. ((1995). Radiation pneumonitis following com‐ bined modality therapy for lung cancer: analysis of prognostic factors. J Clin Oncol. ,

[73] Ruol, A, Castoro, C, Portale, G, Cavallin, F, Sileni, V. C, Cagol, M, Alfieri, R, Corti, L, Boso, C, Zaninotto, G, Peracchia, A, & Ancona, E. (2009). Trends in management and prognosis for esophageal cancer surgery: twenty-five years of experience at a single

[74] Safran, H, Suntharalingam, M, Dipetrillo, T, Ng, T, Doyle, L. A, Krasna, M, Plette, A, Evans, D, Wanebo, H, Akerman, P, Spector, J, Kennedy, N, & Kennedy, T. (2008). Ce‐ tuximab with concurrent chemoradiation for esophagogastric cancer: assessment of

[75] Sai, H, Mitsumori, M, Yamauchi, C, Araki, N, Okumura, S, Nagata, Y, Nishimura, Y, & Hiraoka, M. (2004). Concurrent chemo-radiotherapy for esophageal cancer: com‐ parison between intermittent standard-dose cisplatin with 5-fluorouracil and daily low-dose cisplatin with continuous infusion of 5-fluorouracil. Int J Clin Oncol. , 9(3),

[76] Sasamoto, R, Sakai, K, Inakoshi, H, Sueyama, H, Saito, M, Sugita, T, Tsuchida, E, Ito, T, Matsumoto, Y, Yamanoi, T, Abe, E, Yamana, N, & Sasai, K. (2007). Long-term re‐ sults of chemo-radiotherapy for locally advanced esophageal cancer, using daily lowdose 5-fluorouracil and cis-diammine-dichloro-platinum (CDDP). Int J Clin Oncol. ,

[77] Smithers, B. M, Cullinan, M, Thomas, J. M, Martin, I, Barbour, A. P, Burmeister, B. H, Harvey, J. A, Thomson, D. B, Walpole, E. T, & Gotley, D. C. (2007). Outcomes from salvage esophagectomy post definitive chemo-radiotherapy compared with resection following preoperative neoadjuvant chemo-radiotherapy. Dis Esophagus. , 20(6),

[78] Stahl, M, Stuschke, M, Lehmann, N, Meyer, H. J, Walz, M. K, Seeber, S, Klump, B, Budach, W, Teichmann, R, Schmitt, M, Schmitt, G, Franke, C, & Wilke, H. (2005).

Treat Rev. , 38(6), 599-604.

218 Cancer Treatment - Conventional and Innovative Approaches

Esophagus. , 22(1), 1-8.

13(10), 2606-2612.

149-153.

12(1), 25-30.

471-477.

institution. Arch Surg. , 144(3), 247-254.

toxicity. Int J Radiat Oncol Biol Phys. , 70(2), 391-395.


radiation pneumonitis after concurrent chemoradiation for lung cancer. Int J Radiat Oncol Biol Phys. , 55(1), 110-115.

[99] Yamashita, H, Nakagawa, K, Yamada, K, Kaminishi, M, Mafune, K, & Ohtomo, K. (2008). A single institutional non-randomized retrospective comparison between de‐ finitive chemo-radiotherapy and radical surgery in 82 Japanese patients with resecta‐

Definitive Chemo-Radiotherapy for Resectable Esophageal Cancer — Unresolved Problems Remain

http://dx.doi.org/10.5772/55501

221

[100] Yasunaga, H, Matsuyama, Y, & Ohe, K. Japan Surgical Society. ((2009). Effects of hos‐ pital and surgeon case-volumes on postoperative complications and length of stay af‐

[101] Zuccaro, G. Jr, Rice, T.W., Goldblum, J., Medendorp, S.V., Becker, M., Pimentel, R., Gitlin, L., & Adelstein, D.J. ((1999). Endoscopic ultrasound cannot determine suitabil‐ ity for esophagectomy after aggressive chemo-radiotherapy for esophageal cancer.

ble esophageal squamous cell carcinoma. Dis Esophagus. , 21(5), 430-436.

ter esophagectomy in Japan. Surg Today. , 39(7), 566-571.

Am J Gastroenterol. , 94(4), 906-912.


[99] Yamashita, H, Nakagawa, K, Yamada, K, Kaminishi, M, Mafune, K, & Ohtomo, K. (2008). A single institutional non-randomized retrospective comparison between de‐ finitive chemo-radiotherapy and radical surgery in 82 Japanese patients with resecta‐ ble esophageal squamous cell carcinoma. Dis Esophagus. , 21(5), 430-436.

radiation pneumonitis after concurrent chemoradiation for lung cancer. Int J Radiat

[89] Urschel, J. D, & Vasan, H. of randomized controlled trials that compared neoadju‐ vant chemoradiation and surgery to surgery alone for resectable esophageal cancer.

[90] van de VenC., De Leyn, P., Coosemans, W., Van Raemdonck, D., Lerut, T. ((1999). Three-field lymphadenectomy and pattern of lymph node spread in T3 adenocarci‐ noma of the distal esophagus and the gastro-esophageal junction. Eur J Cardiothorac

[91] Weber, W. A, Ott, K, Becker, K, Dittler, H. J, Helmberger, H, Avril, N. E, Meisetschl‐ äger, G, Busch, R, Siewert, J. R, Schwaiger, M, & Fink, U. (2001). Prediction of re‐ sponse to preoperative chemotherapy in adenocarcinomas of the esophagogastric

[92] Willis, J, Cooper, G. S, Isenberg, G, & Sivak, M. V. Jr, Levitan, N., Clayman, J., & Chak, A. ((2002). Correlation of EUS measurement with pathologic assessment of ne‐ oadjuvant therapy response in esophageal carcinoma. Gastrointest Endosc. , 55(6),

[93] Wilson, K. S, & Lim, J. T. (2000). Primary chemo-radiotherapy and selective oesopha‐ gectomy for oesophageal cancer: goal of cure with organ preservation. Radiother On‐

[94] Wilson, K. S, Wilson, A. G, & Dewar, G. J. (2002). Curative treatment for esophageal cancer: Vancouver Island Cancer Centre experience from 1993 to 1998. Can J Gastro‐

[95] Wouters, M. W, Wijnhoven, B. P, Karim-kos, H. E, Blaauwgeers, H. G, Stassen, L. P, Steup, W. H, Tilanus, H. W, & Tollenaar, R. A. (2008). High-volume versus low-vol‐ ume for esophageal resections for cancer: the essential role of case-mix adjustments

[96] Yamada, K, Murakami, M, Okamoto, Y, Okuno, Y, Nakajima, T, Kusumi, F, Takaku‐ wa, H, & Matsusue, S. (2006). Treatment results of chemo-radiotherapy for clinical stage I (T1N0M0) esophageal carcinoma. Int J Radiat Oncol Biol Phys. , 64(4),

[97] Yamada, M, Kudoh, S, Hirata, K, Nakajima, T, & Yoshikawa, J. (1998). Risk factors of pneumonitis following chemo-radiotherapy for lung cancer. Eur J Cancer. , 34(1),

[98] Yamamoto, S, Ishihara, R, Motoori, M, Kawaguchi, Y, Uedo, N, Takeuchi, Y, Higashi‐ no, K, Yano, M, Nakamura, S, & Iishi, H. (2011). Comparison between definitive che‐ mo-radiotherapy and esophagectomy in patients with clinical stage I esophageal

squamous cell carcinoma. Am J Gastroenterol. , 106(6), 1048-1054.

junction by metabolic imaging. J Clin Oncol. , 19(12), 3058-3065.

based on clinical data. Ann Surg Oncol. , 15(1), 80-87.

Oncol Biol Phys. , 55(1), 110-115.

220 Cancer Treatment - Conventional and Innovative Approaches

Am J Surg. , 185(6), 538-543.

Surg. , 15(6), 769-773.

655-661.

1106-1111.

71-75.

col. , 54(2), 129-134.

enterol. , 16(6), 361-368.


**Chapter 10**

**A Review of Radiation Therapy's Role in Early-Stage**

With the exception of skin cancer, breast cancer is the most commonly diagnosed cancer in women in the United States and the most developed European countries [1]. Although breast cancer has been known to be a major cause of mortality in women living in affluent countries, this disease does not discriminate crossing racial, gender, geograph‐ ic, and economic lines. Encouraging reports indicate there may be a trend toward decreasing breast cancer incidence in countries where there is a decline in hormone replacement therapy [31,6]. Furthermore, it has been reported that breast cancer mortality has fallen in industrialized countries in the last decade [7,36,6]. Reasons for declining

Treatment of breast cancer requires a multidisciplinary approach. The surgeon, medical oncologist, radiation oncologist, and pathologist play a role in developing treatment options for the patient. Radiation therapy has a significant part in the treatment of breast cancer, both

Breast conserving surgery includes partial mastectomy, lumpectomy, tylectomy, wide local excision, and quadrantectomy. These techniques followed by 5-7 weeks of radia‐ tion therapy have been known for over two decades as breast conservation therapy. Initially accepted as a form of breast cancer treatment in Europe, breast conservation therapy is now accepted throughout the world and has gained popularity in the United

> © 2013 Herron et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

distribution, and reproduction in any medium, provided the original work is properly cited.

and reproduction in any medium, provided the original work is properly cited.

**Breast Cancer and an Introduction to Electronic**

Brent Herron, Alex Herron, Kathryn Howell,

Additional information is available at the end of the chapter

mortality may include early detection and better treatment.

for noninvasive and invasive cancers.

States since the early 1980s.

**Brachytherapy**

Daniel Chin and Luann Roads

http://dx.doi.org/10.5772/55621

**1. Introduction**
