Skin Cancer

Skin cancers (skin neoplasms) are named after the type of skin cell from which they arise. Basal cell cancer originates from the lowest layer of the epidermis, and is the most common but least dangerous skin cancer. Squamous cell cancer originates from the middle layer, and is less common but more likely to spread and, if untreated, become fatal. Melanoma, which originates in the pigment-producing cells (melanocytes), is the least common, but most aggressive, most likely to spread and, if untreated, become fatal.

Most cases are caused by over-exposure to UV rays from the sun or sunbeds.Treatment is generally via surgical removal.
Melanoma has one of the higher survival rates among cancers, with over 75% of people surviving 10 years in the UK during 2005–2007.In the UK in 2010, 12,818 people were diagnosed with malignant melanoma, and about 100,000 people were diagnosed with non-melanoma skin cancer. There were 2,746 deaths from skin cancer, 2,203 from malignant melanoma and 546 from non-malignant melanoma. In the US in 2008, 59,695 people were diagnosed with melanoma, and 8,623 people died from it.
Basal cell carcinomas are present on sun-exposed areas of the skin, especially the face. They rarely metastasize and rarely cause death. They are easily treated with surgery or radiation. Squamous cell carcinomas (SCC) are common, but much less common than basal cell cancers. They metastasize more frequently than BCCs. Even then, the metastasis rate is quite low, with the exception of SCC of the lip, ear, and in immunosuppressed patients. Melanomas are the least frequent of the 3 common skin cancers. They frequently metastasize, and could potentially cause death once they spread.
Less common skin cancers include: Dermatofibrosarcoma protuberans, Merkel cell carcinoma, Kaposi's sarcoma, keratoacanthoma, spindle cell tumors, sebaceous carcinomas, microcystic adnexal carcinoma, Pagets's disease of the breast, atypical fibroxanthoma, leimyosarcoma, and angiosarcoma.
The BCC and the SCCs often carry a UV-signature mutation indicating that these cancers are caused by UV-B radiation via the direct DNA damage. However the malignant melanoma is predominantly caused by UV-A radiation via the indirect DNA damage.The indirect DNA damage is caused by free radicals and reactive oxygen species. Research indicates that the absorption of three sunscreen ingredients into the skin, combined with a 60-minute exposure to UV, leads to an increase of free radicals in the skin, if applied in too little quantities and too infrequently.However, the researchers add that newer creams often do not contain these specific compounds, and that the combination of other ingredients tends to retain the compounds on the surface of the skin. They also add the frequent re-application reduces the risk of radical formation.

Signs and symptoms

There are a variety of different skin cancer symptoms. These include changes in the skin that do not heal, ulcering in the skin, discolored skin, and changes in existing moles, such as jagged edges to the mole and enlargement of the mole.

Basal cell carcinoma

Basal cell carcinoma usually presents as a raised, smooth, pearly bump on the sun-exposed skin of the head, neck or shoulders. Sometimes small blood vessels can be seen within the tumor. Crusting and bleeding in the center of the tumor frequently develops. It is often mistaken for a sore that does not heal. This form of skin cancer is the least deadly and with proper treatment can be completely eliminated, often without scarring.
ALTERNATIVE TREATMENT FOR SKIN CANCER

Squamous cell carcinoma

Squamous cell carcinoma is commonly a red, scaling, thickened patch on sun-exposed skin. Some are firm hard nodules and dome shaped like keratoacanthomas. Ulceration and bleeding may occur. When SCC is not treated, it may develop into a large mass. Squamous cell is the second most common skin cancer. It is dangerous, but not nearly as dangerous as a melanoma.

Melanoma

Most melanomas consist of various colors from shades of brown to black. A small amount of melanomas are pink, red or fleshy in color; these are called amelanotic melanomas which tend to be more aggressive. Warning signs of malignant melanoma include change in the size, shape, color or elevation of a mole. Other signs are the appearance of a new mole during adulthood or pain, itching, ulceration, redness around the site, or bleeding at the site. An often-used mnemonic is "ABCDE", where A= asymmetrical, B= "borders" (irregular= "Coast of Maine sign"), C= "color" (variegated), D= "diameter" (larger than 6 mm—the size of a pencil eraser) and E= "evolving."

Other

Merkel cell carcinomas are most often rapidly growing, non-tender red, purple or skin colored bumps that are not painful or itchy. They may be mistaken for a cyst or other type of cancer.

Causes

Ultraviolet radiation from sun exposure is the primary cause of skin cancer.Other factors that play a role include:

• Smoking tobacco
• HPV infections increase the risk of squamous cell carcinoma.
• Some genetic syndromes including congenital melanocytic nevi syndrome which is characterized by the presence of nevi (birthmarks or moles) of varying size which are either present at birth, or appear within 6 months of birth. Nevi larger than 20 mm (3/4") in size are at higher risk for becoming cancerous.
• Chronic non-healing wounds. These are called Marjolin's ulcers based on their appearance, and can develop into squamous cell carcinoma.
• Ionizing radiation, environmental carcinogens, artificial UV radiation (e.g. tanning beds), aging, and light skin color. It is believed that tanning beds are the cause of hundreds of thousands of basal and squamous cell carcinomas.The World Health Organization now places people who use artificial tanning beds in its highest risk category for skin cancer.
• The use of many immunosuppressive medication increase the risk of skin cancer. Cyclosporin A, a calcineurin inhibitor for example increases the risk approximately 200 times, and azathioprine about 60 times.^[16]