*Bone Tumors: Types and Treatments DOI: http://dx.doi.org/10.5772/intechopen.86550*

*Hormone Therapy and Replacement in Cancer and Aging-Related Diseases*

promotion of regulatory T cells [4].

cell survival and proliferation [4].

**4. Tumor biomarkers**

myeloma patients causes an increase in Th17 cells that in turn increase IL-17. IL-17 is an important cytokine that promotes osteoclast and myeloma proliferation and also mediates interactions between T cells and bone metastatic environment. Additionally, myeloid-derived suppressor cells from the bone marrow suppress innate and adaptive immune responses by impairing T-cell antigen recognition and

However, as an individual ages, the hematopoietic red bone marrow gets converted to adipose tissue-rich yellow bone marrow that has a significant impact on the development of bone metastasis. These bone marrow adipocytes not only serve as an energy source but also secrete several pro-inflammatory mediators such as IL-1β, IL-6, leptin, adiponectin, VCAM-1, TNF-α, and CXCL12 that increase cancer

Histological examination of tissue biopsy has been the most commonly used procedure for the diagnosis of bone tumors. Clinical and radiological observations also aid in diagnosis and provide a complete staging of bone cancers. But molecular and genetic markers increase the accuracy of diagnosis, assist in subtyping bone tumors, and also provide an overview of target molecules for designing therapeutic approaches. The biomarkers can be specific or non-specific; diagnostic, prognostic, or therapeutic; and serological, genetic, or histological. The clinical presentation of bone tumors is non-specific, and the most common symptoms include pain and swelling. The clinical features involve limited movement, skin hyperthermia, weight loss, and the presence of a visible mass in the anatomical profile [10].

The serological markers are generally a reflection of osteoblastic and osteoclastic activities in the bone [10]. As mentioned in the earlier sections, breast cancer metastases are mostly osteolytic, whereas metastases of prostate cancer are generally osteoblastic. Therefore, elevated levels of urinary N-terminal cross-linked telopeptide (NTx of type I collagen) and serum carboxyterminal cross-linked telopeptide (ICTP of type I collagen) in solid tumor patients and serum tartrate-resistant acid phosphatase type 5b (TRAcP-5b) in patients with breast tumor metastasis can be used for diagnosis. On the other hand, serum levels of bone-specific alkaline phosphatase (BSAP), procollagen type I N-terminal propeptide (PINP), and OPG

With reference to the genetic changes, sarcomas can be divided into three categories: sarcomas with specific translocations (e.g., Ewing's sarcoma, aneurysmal bone cyst), tumors with gene mutations or amplifications (e.g., chondrosarcomas, fibrous dysplasia), and sarcomas with genetic instability. These cytogenetic changes can be detected using banding and multicolor fluorescence in situ hybridization (FISH), array comparative genomic hybridization (array CGH), targeted detection

There are several markers that are used for prognosis or diagnosis of different

1.Degradation of collagen and the ground substance in the bone (due to prolonged exposure to fluoride) results in increased concentration of serum sialic

acid that can be used as a serum biomarker for osteosarcoma [10].

serve as the biomarkers for prostate cancer metastasis [10, 30].

techniques such as qPCR, and techniques to detect mutation [10].

types of tumors that are discussed below:

**4.1 Osteosarcoma**

*4.1.1 Serum markers*

**20**

