skin cancer

Cancer that forms in tissues of the skin. There are several types of skin cancer. Skin cancer that forms in melanocytes is called melanoma. Skin cancer that forms in basal cells (small, round cells in the base of the outer layer of skin) is called basal cell carcinoma. Skin cancer that forms in squamous cells (flat cells that form the surface of the skin) is called squamous cell carcinoma. Skin cancer that forms in neuroendocrine cells (cells that release hormones in response to signals from the nervous system) is called neuroendocrine carcinoma of the skin. Most skin cancers form in older people on parts of the body exposed to the sun or in people who have weakened immune system. Estimated new cases and deaths from skin (nonmelanoma) cancer in the United States in 2009: New cases: more than 1,000,000 & Deaths: less than 1,00 The skin is the body’s largest organ. It protects against heat, sunlight, injury, and ifection. Skin also helps control body temperature and stores water, fat, and Vitamin D. The skin has several layers, but the two main layers are the epidermis (upper or outer layer) and the dermis (lower or inner layer). Skin cancer begins in the epidermis, which is made up of 3 kinds of cell :no :1 Squamouc cell. Thin, flat cells that form the top layer of the epidermis.

Basal cell: Round cells under the squamous cells.

Melonocytes: Found in the lower part of the epidermis, these cells make melanin, the pigment that gives skin its natural color. When skin is exposed to the sun, melanocytes make more pigment, causing the skin to darken. Skin cancer can occur anywhere on the body, but it is most common in skin that is often exposed to sunlight, such as the face, neck, hands, and arms. There are several types of cancer that start in the skin. The most common types are basal cell carcinoma and squamous cell carcinoma which are nonmelanoma Skin cancer . Actinic Keratosis is a skin condition that sometimes develops into squamous cell carcinoma.

Nonmelanoma skin cancers rarely spread to other parts of the body.Melanoma, the rarest form of skin cancer, is more likely to invade nearby tissues and spread to other parts of the body. See the following PDQ summaries for information on melanoma and other kinds of skin cancer: Two in every 3 Australians will be affected by skin cancer over their lifetime. The prevalence of skin cancer will continue to increase due to the ageing population and represents a significant problem in our community.

Cure of early (T1-2) de novo cutaneous squamous cell carcinoma (CSCC) treated with either curative intent surgery or radiotherapy is 85-100%. However, the cure rate for locally advanced, recurrent, or metastatic disease to regional nodes following surgery alone are much lower, in the order of 20-70%. Metastatic CSCC is the most common malignancy of the parotid region in Australia . The 5 year loco-regional control with surgery alone is in the order of 40%-45%. The addition of post-operative radiotherapy improves loco-regional control by 15-20%, and is therefore considered the standard of care in this group of patients. Recent data have shown that synchronous post-operative chemo-radiotherapy is superior to post-operative radiotherapy alone in "high-risk" mucosal head and neck squamous cell carcinoma (HNSCC). However, to date, there is no evidence from randomised trials that such a benefit exists in CSCC of the head and neck. At present there is little consensus amongst clinicians in Australia as to who should receive post-operative chemo-radiotherapy in CSCC. Although tumour control rates may be improved, the addition of chemotherapy may also significantly increase treatment related toxicity. Nonetheless, some centres have adopted the use of post-operative chemo-radiotherapy in selected patients with CSCC based on extrapolation from mucosal sites. This has resulted in a wide variability in practice for this disease. Australia is uniquely placed to perform such a trial comparing post-operative chemo-radiotherapy to post-operative radiotherapy alone in high-risk CSCC due to the high rate of skin cancer. Currently there are limited data to guide management of patients with resected CSCC who are at high risk for recurrence. While it is reasonable to hypothesize that concurrent chemotherapy in this setting will confer a similar benefit to that seen in mucosal HNSCC, this can only be established by a randomized trial as proposed. If the addition of chemotherapy is shown to be beneficial and safe, then these results are likely to be translated into standard practice both nationally and internationally quite rapidly. On the other hand, if the treatment is found to be ineffective then patients will be spared the unnecessary toxicity and inconvenience associated with the addition of chemotherapy. A further important aspect of this trial will be the assessment of patient-related outcomes using a validated quality of life questionnaire. It will be important to ascertain whether any improvement in locoregional control due to the addition of chemotherapy, is also associated with improvement in quality of life compared to the control arm.

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