Melanoma
Melanoma is a type of cancer that begins in the melanocytes. These are cells that make the pigment melanin. Melanomas often start in moles on the skin. They can also start in other parts of the body that have melanocytes. This includes the fingernails, toenails, eyes, and the GI tract. Rarely, melanomas can also form in the nasal passages, sinuses, or in the genital area. Melanoma can spread (metastasize) to other parts of the body.