A form of cancer that begins in melanocytes (cells that make the pigment melanin). It may begin in a mole (skin melanoma), but can also begin in other pigmented tissues, such as in the eye or in the intestines. Most melanocytes are in the skin. See the picture of a melanocyte and other skin cells.
Melanoma can occur on any skin surface. In men, it’s often found on the skin on the head, on the neck, or between the shoulders and the hips. In women, it’s often found on the skin on the lower legs or between the shoulders and the hips.
Melanoma is rare in people with dark skin. When it does develop in people with dark skin, it’s usually found under the fingernails, under the toenails, on the palms of the hands, or on the soles of the feet.
Symptoms of Melanoma
Often the first sign of melanoma is a change in the shape, color, size, or feel of an existing mole. Melanoma may also appear as a new mole. Thinking of “ABCDE” can help you remember what to look for:
- Asymmetry: The shape of one half does not match the other half.
- Border that is irregular: The edges are often ragged, notched, or blurred in outline. The pigment may spread into the surrounding skin.
- Color that is uneven: Shades of black, brown, and tan may be present. Areas of white, gray, red, pink, or blue may also be seen.
- Diameter: There is a change in size, usually an increase. Melanomas can be tiny, but most are larger than the size of a pea (larger than 6 millimeters or about 1/4 inch).
- Evolving: The mole has changed over the past few weeks or months.
Melanomas can vary greatly in how they look. Many show all of the ABCDE features. However, some may show changes or abnormal areas in only one or two of the ABCDE features.
In more advanced melanoma, the texture of the mole may change. The skin on the surface may break down and look scraped. It may become hard or lumpy. The surface may ooze or bleed. Sometimes the melanoma is itchy, tender, or painful.
Stages of Melanoma
These are the stages of melanoma:
Stage 0: The melanoma involves only the top layer of skin. It is called melanoma in situ.
Stage I: The tumor is no more than 1 millimeter thick (about the width of the tip of a sharpened pencil.) The surface may appear broken down. Or, the tumor is between 1 and 2 millimeters thick, and the surface is not broken down.
Stage II: The tumor is between 1 and 2 millimeters thick, and the surface appears broken down. Or, the thickness of the tumor is more than 2 millimeters, and the surface may appear broken down.
Stage III: The melanoma cells have spread to at least one nearby lymph node. Or, the melanoma cells have spread from the original tumor to tissues nearby.
Stage IV: Cancer cells have spread to the lung or other organs, skin areas, or lymph nodes far away from the original growth. Melanoma commonly spreads to other parts of the skin, tissue under the skin, lymph nodes, and lungs. It can also spread to the liver, brain, bones, and other organs.
Treatment for Melanoma
Surgery: In general, the surgeon will remove the cancerous growth and some normal tissue around it. This reduces the chance that cancer cells will be left in the area. There are several methods of surgery for skin cancer. The method your doctor uses depends mainly on the type of skin cancer, the size of the cancer, and where it was found on your body.
Chemotherapy: Chemotherapy uses drugs to kill cancer cells. Drugs for skin cancer can be given in many ways. Read more about Chemotherapy here.
Photodynamic Therapy: Photodynamic therapy (PDT) uses a drug along with a special light source, such as a laser light, to kill cancer cells. PDT may be used to treat very thin, early-stage basal cell or squamous cell skin cancer (Bowen disease).
The drug is either rubbed into the skin or injected intravenously. The drug is absorbed by cancer cells. It stays in cancer cells longer than in normal cells. Several hours or days later, a special light is focused on the cancer. The drug becomes active and destroys the cancer cells.
The side effects of PDT are usually not serious. PDT may cause burning or stinging pain. It also may cause burns, swelling, or redness. It may scar healthy tissue near the growth. If you have PDT, you will need to avoid direct sunlight and bright indoor light for at least 6 weeks after treatment.
Biological Therapy: Some people with advanced melanoma receive a drug called biological therapy. Biological therapy for melanoma is treatment that may improve the body’s natural defense (immune system response) against cancer.
One drug for melanoma is interferon. It’s injected intravenously (usually at a hospital or clinic) or injected under the skin (at home or in a doctor’s office). Interferon can slow the growth of melanoma cells.
Another drug used for melanoma is interleukin-2. It’s given intravenously. It can help the body destroy cancer cells. Interleukin-2 is usually given at the hospital.
Other drugs may be given at the same time to prevent side effects. The side effects differ with the drug used, and from person to person. Biological therapies commonly cause a rash or swelling. You may feel very tired during treatment. These drugs may also cause a headache, muscle aches, a fever, or weakness.
Radiation Therapy: Radiation therapy uses high-energy rays to kill cancer cells. The radiation comes from a large machine outside the body. It affects cells only in the treated area. You will go to a hospital or clinic several times for this treatment. Read more about Radiation Therapy here.