**1. Introduction**

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60 Updates on Cancer Treatment

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Pain is one of the most frequent and distressing symptoms occurring in cancer patients. Pain is present in 36–61% of cancer patients depending on the histopathological tumor type, on the stage of disease, and patient setting.[1, 3]

Sixty-four percent of patients with advanced cancer are believed to experience substantial pain as a consequence of the neoplastic condition.[4]

Unfortunately, cancer pain is often neglected and undertreated, resulting in a significantly unfavorable impact on the quality of life of the patients and their families. [5]

The National Cancer Institute estimates 1, 660, 290 new patients to be diagnosed with cancer, and about 580, 350 Americans were expected to die from cancer in any sites in 2013. [6]

Cancer pain management relies upon a comprehensive assessment characterized by pain symptoms in terms of phenomenology and pathogenesis, assessing the relation between pain and the causative disease, and clarifying the impact of pain and related co-morbidities on the patient's quality of life.

Despite recent improvements in the cancer management, obstacles to optimal cancer pain management still remain.

Additionally, the lack of psychological and psychiatric support services to support the treatment of cancer pain remains a serious issue.[7]

Hurdles to the treatment of cancer pain have been recognized, including a variety of educa‐ tional, attitudinal and institutional obstacles. As regards the education in pain management,

there appears to be a deficiency in the training of physicians and nurses. Both physicians and nurses indicated that "inability to properly assess the pain" and "inadequate knowledge about pain management" ranked among the most relevant barriers preventing a multidisciplinary approach to pain treatment and adequate cancer pain management. [8]

Despite the increasing availability of pain medications, pain continues to be deemed as moderate-to-severe in more than 50% of cancer patients.

According to a recent population-based study, investigating cancer pain in eleven European countries and Israel, 56% of patients suffered from moderate to severe pain in the previous months, and 69% reported pain-related difficulties hindering everyday activities. [9]

A systematic review completed in 2007 showed that cancer pain is present in 64% of patients with metastatic, advanced disease, in 59% of subjects undergoing cancer-related therapies. Despite effective, curative treatment, a moderate-to-severe pain intensity being reported in more than one third of all cancer patients.

Pain is present in over 50% of cancer patients, reaching higher percentages in patients with cancer at specific sites, such as stomach, uterus, lung, prostate, cervico-facial district, biliary tract, breast, colon, brain, pancreas, cervix, and ovary. [10]
