It is a more serious problem than the more common skin cancers, basal cell cancer or squamous cell cancer. Unlike these cancers, melanoma often will spread (metastasize) to other parts of the body. About 68,720 patients in the US will be diagnosed with melanoma in 2009 and 8650 will die from this cancer.
It is the 5th most common disease in men and 6th most common disease in women.
Approximately 83% of diagnoses are made from the local site.
Melanoma can spread by local extension (through lymphatics) and/or by hematogenous routes (through the bloodstream) to distant sites. The risk of relapse may decrease over time, but late relapses are not uncommon.
Most melanomas are dark, but some are not, and may be flesh colored or pink to red. If there is a serious question of skin cancer, the mole or pigmented area will be cut out (local excision). This is usually done in a doctor’s office. It is important that this remove the entire mole if possible.
In the earliest melanomas, the abnormal cells are found only in the outer layer of skin cells and do not invade the body. It is more advanced if the growth goes deeper than 4 millimeters (less than 1/6 of an inch) into the skin. Most melanomas fall between these two extremes. More serious still are melanomas that have spread to the body tissue below the skin, show additional tumor around original tumor (satellite tumors), or have spread to lymph nodes or other organs.
Surgery is the primary treatment of all stages of melanoma. A second procedure is normally done to ensure complete removal of the melanoma. Complete removal of all the melanoma before it has spread is the only sure cure for melanoma. Usually, the biopsy site and a rim of apparently normal skin are removed. This is called a re-excision. The amount removed depends on how deep the melanoma has grown. Skin may have to be taken from another area of the body and put (or “grafted”) where the cancer has been taken out.
Chemotherapy uses drugs to kill cancer cells. However, chemotherapy has not been shown to be very effective in treating melanoma. Clinical studies are being done to find chemotherapy drugs that are more effective. Radiation uses x-rays to kill cancer cells and shrink tumors. Radiation shrinks and slows, but does not usually cure, melanoma.
Treatment of advanced (stage III) melanoma may involve surgical removal of the tumors and any affected lymph nodes, followed by systemic or local chemotherapy with single or multiple agents. The five-year survival rate for treated Stage III patients is about 60 percent, and both the disease and the treatment often compromise quality of life.