Malignant Melanoma – 5% of all skin cancers.
Malignant melanoma is a potentially serious type of skin cancer. It is caused by the uncontrolled growth of pigment cells, which are also called melanocytes and it appears as a spot on the skin that contains cancer cells.
Normal melanocytes are found in the basal layer (bottom part of the outer layer) of the skin. The melanocytes produce a protein called melanin, which protects the skin by absorbing ultraviolet (UV) radiation. Non-cancerous growth of melanocytes results in moles (properly called benign melanocytic naevi) and freckles (ephelides and lentigines). Cancerous growth of melanocytes results in melanoma. Even where the spot appears small, as with any cancer, the cells can grow and invade other cells and other parts of the body.