Incisional biopsy site in an acral lentiginous melanoma on the sole of the foot of a 56 year old African American male patient. An incisional biopsy only removes part of the tumour. Melanoma is a form of skin cancer that arises from melanocytes, the cells that produce melanin, the pigment that gives skin its colour. Acral melanoma is a rare form that affects the hands and feet and is most common in people with darker skin. The main cause of melanoma is exposure to ultraviolet radiation in sunlight. It is an aggressive cancer that often spreads (metastasizes) to other parts of the body. Treatment is with surgical excision of the melanoma.