Melanoma is a cancer that forms in the pigment cells (melanocytes) of the skin. There were approximately forty-seven thousand new cases in the United States in the year 2000, nearly eight thousand of which were fatal, mostly due to metastases. Reports of melanoma cases doubled in frequency during the last decade of the twentieth century. Solar exposure and genetic factors are responsible for the majority of cases.

Reduction in exposure to ultraviolet light, especially early in life, and regular screening of those at increased risk are the best approaches to reducing mortality from melanomas. The overall five-year survival rate is 85 percent, and surgical excision of early tumors is usually curative. More effective treatment for advanced malignant melanoma is needed, however.

ARTHUR J. SOBER

(SEE ALSO: Cancer; Skin Cancer; Ultraviolet Radiation)