Skin cancer, malignant melanoma, is a type of skin tumor that is characterized by the cancerous growth of melanocytes, which are cells that produce a dark pigment called melanin.

Cancer of the skin is the most common type of cancer and continues to grow in incidence. Skin cancer starts in the top layer of skin (the epidermis) but can grow down into the lower layers, the dermis and the subcutaneous layer. There are three main types of cells located in the epidermis, each of which can become cancerous. Melanocytes are the pigmented cells that are scattered throughout the skin, providing protection from ultraviolet (UV) light. Basal cells rest near the bottom of the epidermis and the layer of cells that continually grow to replace skin. The third type of epidermal cell is the squamous cells which make up most of the cells in human skin.

Malignant...