Melanoma is the most dangerous type of skin cancer. It is the leading cause of death from skin disease.
Melanoma can also involve the colored part of the eye. For information about that form of melanoma, see melanoma of the eye.
Skin cancer - melanoma
Melanoma is caused by changes in cells called melanocytes, which produce a skin pigment called melanin. Melanin is responsible for skin and hair color. It can appear on normal skin, or it may begin as a mole or other area that has changed in appearance. Some moles that are present at birth may develop into melanomas.
There are four major types of melanoma:
Rarely, melanomas appear in the mouth, iris of the eye, or retina at the back of the eye. They may be found during dental or eye examinations. Although very rare, melanoma can also develop in the vagina, esophagus, anus, urinary tract, and small intestine.
Melanoma is not as common as other types of skin cancer. However, the rate of melanoma is steadily increasing.
The risk of developing melanoma increases with age. However, it is also frequently seen in young people.
You are more likely to develop melanoma if you:
Other risk factors include:
A mole, sore, lump, or growth on the skin can be a sign of melanoma or other skin cancer. A sore or growth that bleeds, or changes in skin coloring may also be a sign of skin cancer.
The ABCDE system can help you remember possible symptoms of melanoma:
The key to successfully treating melanoma is recognizing symptoms early. You might not notice a small spot if you don't look carefully. Have yearly body checks by a dermatologist, and examine your skin once a month. Use a hand mirror to check hard-to-see places. Call your doctor if you notice anything unusual.
Your doctor will check your skin and look at the size, shape, color, and texture of any suspicious areas.
If your doctor thinks you might have skin cancer, a piece of skin will be removed and sent to a lab for examination under a microscope. This is called a skin biopsy. There are different types of skin biopsies. All or part of the growth will be removed.
A sentinel lymph node (SLN) biopsy may be done in some people with melanoma to see if the cancer has spread to nearby lymph nodes.
Once melanoma has been diagnosed, CT scans or other types of x-ray tests may be done to see if the cancer has spread.
Surgery is needed to treat melanoma. The skin cancer and some surrounding tissue will be removed. How much skin is removed depends on how deep the melanoma has grown.
If the cancer has spread to nearby lymph nodes, these lymph nodes may also be removed. After surgery, you may receive a medicine called interferon.
Treatment is more difficult when the melanoma has spread to other organs. When it spreads to other organs, it usually cannot be cured. Treatment involves shrinking the skin cancer and making you as comfortable as possible. You may receive:
If you have melanoma that is hard to treat, you might consider enrolling in a clinical trial. Ask your doctor for more information. Researchers continue to study new treatments.
See: Cancer support group
How well a patient does depends on many things, including how quickly the cancer was diagnosed and how far it has spread.
If caught early, some melanomas can be cured.
Melanoma that is very deep or has spread to the lymph nodes is more likely to return after treatment. If it is deeper than 4 mm or has spread to the lymph nodes, you are more likely to have the cancer spread to other tissues and organs.
Melanoma usually cannot be cured when the cancer has spread beyond the skin and nearby lymph nodes.
If you have had melanoma and recovered, it is very important to examine your body regularly for any unusual changes. Your risk for melanoma is increased once you have had this cancer. Melanoma may return years later.
Melanoma can spread to other parts of the body very quickly.
Melanoma treatment can cause side effects, including pain, nausea, and fatigue.
Call your health care provider if you notice a new growth or any other changes in your skin. You should also call if an existing spot becomes painful or swollen, or if it starts to bleed or itch.
The American Cancer Society recommends professional skin examinations every year for people older than 40, and every 3 years for people ages 20 - 40.
You should also examine your skin once a month, using a mirror to check hard-to-see places. Call your doctor if you notice any changes.
The best way to prevent skin cancer is to reduce your exposure to sunlight. Ultraviolet light is most intense between 10 a.m. and 4 p.m., so try to avoid sun exposure during these hours. Protect the skin by wearing hats, long-sleeved shirts, long skirts, or pants.
Other important facts to help you avoid too much sun exposure:
Goodson AG, Grossman D. Strategies for early melanoma detection: Approaches to the patient with nevi. J Am Acad Dermatol. 2009;60:719-735.
Hodi FS, O'Day SJ, McDermott DF, et al. Improved survival with ipilimumab in patients with metastatic melanoma. N Eng J Med. 2010;363:711-723.
Lange JR, Fecher LA, Sharfman WH, et al. Melanoma. In: Abeloff MD, Armitage JO, Nierderhuber JE, Kastan MB, McKenna WG, eds. Abeloff's Clinical Oncology. 4th ed. Philadelphia, Pa: Churchill Livingstone; 2008:chap 73.
National Comprehensive Cancer Network. NCCN Medical Practice Guidelines and Oncology: Melanoma. V.4.2011.