What Is Melanoma?

Melanoma is a type of skin cancer. It begins when pigment-producing (color-producing) cells, called melanocytes, begin to change and grow uncontrollably, forming a mass called a tumor. A tumor can be benign (noncancerous) or malignant (cancerous, meaning it can spread to other parts of the body). Melanoma can appear in an area no different from the surrounding skin, or it can develop from or near a mole.

Skin is made up of two main layers: the epidermis (outer layer of skin) and the dermis (inner layer of skin). The deeper layer of the epidermis contains melanocytes. Melanoma, the most aggressive form of skin cancer, starts in melanocytes and can grow deep into the dermis, invading lymph and blood vessels. Although it is found most frequently on the skin of men's backs or on women's legs, melanoma can occur anywhere on the body, including the head and neck.

The initial type of treatment is determined by the thickness of the tumor. Treatment of the primary (initial) melanoma usually involves surgery, which often cures early stage or thin melanoma.

After removal of the primary melanoma, additional surgery may be needed to make sure that the melanoma will not come back in the same area and to find out if the melanoma has spread to nearby lymph nodes (tiny, bean-shaped organs that help fight infection). This procedure, using a technique called sentinel lymph node mapping, can help your doctors evaluate risk and decide if immunotherapy, radiation therapy and chemotherapy may be needed. Scientists are also investigating new ways to treat advanced melanoma, including targeted therapy, gene therapy and vaccine therapy.