Skin cancer is most common type in the U.S.

Last week I discussed how to protect yourself from the sun. This week I’d like to talk about skin cancer itself: the types of skin cancer, where it comes from, how it is treated, and what to look for.

Skin cancer is the most common type of cancer in the U.S. It is also one of the most preventable because exposure to ultra violet light, the harmful rays of the sun, is the most important preventable risk factor for developing skin cancer.

There are three common types of skin cancer. All three kinds of cancer form when UV rays damage the genetic material, DNA, in the skin cells, causing unrestrained growth. Two of these are called non-melanoma skin cancers, or NMSC. They account for more than 90 percent of skin cancers. The most common NMSC is called basal cell carcinoma. The other NMSC is called squamous cell carcinoma.

These kinds of cancers are relatively slow growing and don’t easily metastasize, or spread, to other areas of the body. This allows them to be easily treated by one of several techniques; often, all it takes is a simple surgery to biopsy the spot, which may allow simultaneous removal of the entire cancer. Other options include cryosurgery, which uses liquid nitrogen to freeze the area, topical chemotherapy cream, or a technique called curettage and electrodessication, which involves scraping away the cancer cells, then using an electrical current to kill any remaining cancer and stop the bleeding.

The third type, melanoma, is the most infamous type of skin cancer. Melanoma is far less common, but also more serious, than other types of skin cancer. It is more likely to invade deeper tissues and spread to other areas of the body. Melanoma forms in the pigment producing cells of the skin, called melanocytes. If found early, it is easily treated the same way as other skin cancers, but melanoma may require more aggressive chemotherapy if it has spread.

You should check yourself regularly for changes in your skin that might signal cancer, then see a doctor if you notice anything worrisome. Change is the most important sign to be aware of; new moles after age 30, and moles that bleed, itch, or grow quickly are potential culprits. Also look for a sore that won’t heal or one that keeps reappearing. The ABC’s of moles is a good way to remember what to look for:

A: Asymmetry — the mole doesn’t look the same on both halves

B: Border — The edges of the mole are jagged, uneven, or blended into the surrounding skin.

C: Color — Any change in the color of a mole, darker or lighter, or multiple colors in one mole.

D: Diameter — The mole is larger than a pencil eraser (1/4 inch).

E: Elevation — The mole is raised and uneven.

The best way to prevent skin cancer is to protect yourself from the sun. Look back to last week’s article for more information on sun safety, and check your skin regularly. I hope you have a safe and enjoyable summer, and that this information has been helpful!

n Stephanie Gering is a second year medical student at the University of Washington. She is participating in a summer clinical medicine program under the supervision of Scott Dunn, M.D., a member of Bonner General Hospital’s medical staff. The facts in this article were supplied by the American Cancer Society. For more information, visit www.cancer.org.