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Melanoma is skin cancer of the melanocytes, the cells that produce skin color and give moles their dark color.

Moles are collections of melanocytes. Normally, moles are benign. Sometimes, however, a mole can develop into melanoma. A new mole may also be an early sign of melanoma. The three major types of skin cancer are basal cell, squamous cell, and melanoma. Basal cell and squamous cell are the two most common. Melanomas account for less than 5% of all skin cancer cases; however, they are more dangerous because they are far more likely to spread to other parts of the body.

Melanoma occurs when melanocytes divide without control or order. The disease typically starts in the skin, but it also may arise in other areas where melanocytes are found, such as in the eyes, digestive system, nail beds, or lymph nodes.

Ultraviolet radiation from the sun is the main cause of skin cancer. Artificial radiation from sun lamps and tanning booths can also cause skin cancer. Exposure