Melanoma is a cancer that originates in pigment-producing cells known as melanocytes. It usually starts in the skin, but the mouth, eyes or internal organs can also be affected. Although less common than other types of skin cancer, melanoma is more likely to spread—a process known as metastasis—and it is much more likely to be deadly.
Melanoma rates have been rising in recent decades. Over 100,000 people will develop melanoma, and nearly 7,000 will die from it this year, according to the American Cancer Society.
White people are most likely to develop melanoma, but it can also occur in people with dark skin. Black people may develp a form called acral lentiginous melanoma on the palms, soles of the feet or under fingernails or toenails.
The main risk factor for melanoma is exposure to ultraviolet radiation from the sun or tanning beds. The best way to protect yourself is to avoid the sun during the middle of the day, use a broad-spectrum sunscreen and cover your skin.
The most common sign of melanoma is an unusual dark spot on the skin—but most moles are not cancerous. Other warning signs include redness or swelling around a mole, oozing or bleeding moles and sores that don’t heal. Check your skin regularly, and report suspicious changes to your doctor.
The sooner melanoma is detected, the easier it is to treat. Small, localized cancer can often be surgically removed. Nearby lymph nodes may also be removed and tested to determine whether the cancer has spread. Radiation therapy may be used to kill malignant cells that remain after surgery or to shrink cancer that cannot be removed.
Metastatic melanoma that has spread elsewhere is more difficult to treat. Chemotherapy does not work very well against melanoma, and it is usually not the first line of treatment.
Targeted therapies work against cancer with specific characteristics, often blocking proteins that play a role in cell growth. About half of all melanomas have a BRAF gene mutation, which makes them susceptible to BRAF inhibitors. Other drugs target the MEK protein; BRAF and MEK inhibitors often work better in combination.
The newest type of treatment helps the immune system fight cancer. Because melanoma has more mutations than other cancers, it is easier for the immune system to recognize, and it responds better to immunotherapy. Melanoma was the first approved indication for checkpoint inhibitors, which restore T-cell activity against cancer.
Treatment for melanoma has evolved rapidly in recent years, and survival rates have improved dramatically. What’s more, new treatment approaches are being developed. Ask your doctor whether a clinical trial might be a good option for you.