Melanoma is less common but more dangerous than other types of skin cancers. Melanomas are cancers of the pigment-producing cells in the skin, known as melanocytes. Normally these cells produce melanin which protect the skin from UV damage from the sun. When melanocytes become cancerous, they have the ability to grow rapidly and develop into malignant tumors, making melanoma a serious and life-threating disease. Melanomas can arise within an existing mole, but most develop on normal skin. Skin self-exams are encouraged and can help find concerning lesions when they are still very treatable. Early diagnosis and treatment is the best course of action.