Melanoma is a cancerous (malignant) tumor that begins in the melanocytes. Melanocytes are the cells that produce the skin coloring or protective pigment called melanin. Melanin helps protect the deeper layers of the skin from the harmful effects of sun rays. Melanoma cells still produce melanin, but the cells grow uncontrollably. This is why melanoma cancers have mixed shades of tan, brown and black skin cells.
It is not certain how all cases of melanoma develop. However, it is clear that excessive sun exposure, especially severe blistering sunburns early in life, can promote melanoma development. There is evidence that ultraviolet radiation used in indoor tanning equipment may cause melanoma. The risk for developing melanoma may also be inherited.
Immunosuppression—impairment of the immune system, which protects the body from foreign entities, such as germs or substances that cause an allergic reaction. This may occur as a consequence of some diseases or can be due to medications prescribed to combat autoimmune diseases or prevent organ transplant rejection.
Lentigo maligna melanoma usually occurs in the elderly. It is most common in sun-damaged skin on the face, neck, and arms. The abnormal skin areas are usually large, flat, and tan with intermixed areas of brown.
Acral-lentiginous melanoma: is the least common form of melanoma. It appears as a black discoloration on palms, fingers, soles and toes (including the skin under the nails). African-Americans and Asians are more likely to develop this form of melanoma.
Often, the first sign of melanoma is a change in the size, shape, color, or feel of an existing mole. Most melanomas have a black or blue-black area. Melanoma also may appear as a new mole. It may be black, abnormal, or “ugly looking.”
Minimizing sun exposure is the best way to prevent skin damage, including many types of skin cancer
:Protect your skin from the sun when you can — wear protective clothing such as hats, long-sleeved shirts, long skirts, or pants.
Try to avoid exposure during midday, when the sun is most intense.
Use sunscreen with an SPF of at least 15. Apply sunscreen at least one-half hour before sun exposure, and reapply frequently.
Treatment for melanoma begins with the surgical removal of the melanoma and some normal-looking skin around the growth. Removal of the normal-looking skin is known as taking margins, and is done to be sure no melanoma is left behind. Early melanoma limited to the outermost layer of the skin (the epidermis) is known as melanoma in situ (in place), and simple surgical removal produces virtually a 100 percent cure rate. If left untreated, the melanoma grows deeper in the skin and is more likely to produce a life-threatening situation.
The most commonly used treatments are surgery, radiation therapy, and chemotherapy. Surgery requires removal of part of the skin. Radiation therapy involves the use of high-energy rays to destroy cancer cells. Chemotherapy is the use of anti-cancer medications given intravenously or taken by mouth.
Radiation therapy uses high energy x-rays to kill cancer cells, or involves the injection of radioisotopes in the areas where cancer has been found. The use of Alpha-Interferon to bolster the immune system has been tried with about a 10% success rate.