Dermatology Facts

Dermatology Facts—Melanoma


Melanoma is cancer that begins in melanocytes. It is the most serious type of skin cancer. Melanoma can begin as a new spot on the skin, or it can start in an existing mole. It occurs when melanocytes become abnormal, divide too often, and grow without control or order, producing too much tissue. The mass of extra tissue is called a tumor.

Melanoma can look like an atypical mole. A dermatologist can tell whether an abnormal-looking mole should be closely watched or should be removed and checked for melanoma.

Melanoma can be cured by surgery if it is discovered early when the tumor is thin (before cancer cells have grown downward from the skin surface) and before the cells have begun to spread to other places in the body. However, if melanoma is not found early, the cancer cells can invade and destroy nearby healthy skin. They also can spread and form tumors throughout the body (metastasis), making the disease much harder to control and cause serious harm, even death.

It is possible to detect melanoma early, when the disease can be cured with simple surgery. Learning about prevention and early detection is important for everyone, especially people who have a higher-than-average risk for melanoma. Those at increased risk include those who have many atypical nevi or a large number of moles. Other people at increased risk for melanoma are those who:

  • have already had the disease;
  • have close relatives who have had the disease;
  • have a history of one or more bad blistering sunburns as a child or teenager; or
  • have fair skin that burns or freckles easily.

It is important to keep in mind that not everyone who has dysplastic nevi or other risk factors for melanoma gets the disease; in fact, most do not. Also, about half the people who develop melanoma do not have atypical nevi; in fact, they may not have any known risk factor for the disease.