Detailed Information on Melanoma

Melanoma is the most risky type of skin cancer. Melanoma is a malignant tumor of melanocytes which are found predominantly in skin but also in the bowel and the eye. It is due to wild growth of pigment cells, called melanocytes. Melanoma is most common in white skinned individuals, but it may rarely develop in those with dark skin as well. About one in fifteen white skinned New Zealanders are expected to develop melanoma in their lifetime. Melanoma can occur in adults of any age but is very rare in children.

Melanoma can also include the colored area of the eye. Malignant melanoma accounts for 75 percent of all deaths linked with skin cancer. There are four main types of melanoma. Superficial spreading melanoma is the most frequent type of melanoma. It is usually flat and irregular in shape and color, with varying shades of black and brown. Nodular melanoma usually starts as a raised area that is dark blackish-blue or bluish-red, although some are without color. Lentigo maligna melanoma usually occurs in the elderly. It is most common in sun-damaged skin on the face, neck, and arms.

Acral lentiginous melanoma is the least common form of melanoma. It generally occurs on the palms, soles, or under the nails and is more familiar in African Americans. Melanoma can extend very quickly. Melanoma may show on normal skin, or it may begin at a mole or other area that has changed in appearance. Some moles present at birth may develop into melanomas. The development of melanoma is related to sun exposure, particularly to sunburns during childhood, and is most common among people with fair skin, blue or green eyes, and red or blond hair. Melanomas are removed surgically.

The level of surgery depends on the thickness of the melanoma and its site. Most thin melanomas do not require widespread surgery. They are generally removed using a local anaesthetic, and the fault stitched up. A small area of normal skin around the melanoma is also excised to make sure that all the melanoma cells have been removed. Radiation therapy is frequently used after surgical resection for patients with locally or regionally advanced melanoma. High risk melanomas may require adjuvant treatment.  Various chemotherapy agents are used, including dacarbazine; immunotherapies as well as local perfusion are used.