MEDICAL SURFARI: SIMPLE SUN SAFETY CAN PREVENT SKIN CANCER

In our culture a golden brown tan is considered attractive and most of us think we look healthier with a tan. Looks, however, can be deceiving. The fact is that our tanned skin is not healthier. The same damaging process that causes a painful, red sunburn occurs when we tan. Although most skin cancers don't appear until after age 50, the damaging effects of tanning and sunburn are cumulative, and they begin when we are young. Therefore skin cancer protection should start in childhood to prevent skin cancer later in life.

Over the past 60 years, damage to the planet's ozone layer has increased the amount of harmful light that reaches your skin. Cumulative exposure to the sun's dangerous ultraviolet rays is a chief factor in developing skin cancer.

There are two types of ultraviolet light from the sun that impact and affect the skin. Ultraviolet A (UVA), is a long wavelength light, and smooth ultraviolet B (UVB), a shorter and stronger form of sunlight. With sufficient exposure UVB rays may cause sunburn. UVA rays don't cause sunburns, and for many years doctors thought that they were not a cancer threat. However, we now know that even small amounts of UVA light can enhance the damaging and cancer-causing effects of UVB rays.

UVA rays are also able to penetrate the skin more deeply than UVB rays and damage the skin's elastic structure. This is the kind of damage is thought to be related to "aging." A single blistering sunburn can damage your skin cells enough to double your chances of developing skin cancer.

Skin cancer is the most common type of cancer in the United States. One out of every six Americans develops skin cancer in his or her lifetime. Most skin cancers are slow growing basal cell or squamous cell carcinoma. However, malignant melanoma is a fast growing, potentially fatal skin cancer that is related to sun exposure and is on the rise. About 38,000 people will be diagnosed with this type of skin cancer this year.

The key to successful treatment of skin cancer is early detection. Because skin cancers are more common among people who have fair complexion, dermatologists recommend that these high-risk adults have a complete skin examination at regular intervals. Adults should also become familiar with the appearance of their own skin and practice good skin self-examination once a month.

Any changes in the appearance of a mole should be brought to a doctor's attention. Watch for the A,B,C,D warning signs of melanoma:

A: asymmetry -- one half of the mole does not match the other

B: border -- edges of the mole are ragged, notched or blurred

C: color -- color of mole is not uniform

D: diameter -- the mole is larger than a pencil eraser (greater that 6 mm)

The most important thing that you can do to prevent skin cancer is to avoid burning your skin. Avoid the sun between 10 a.m. and 4 p.m. when its rays are strongest. Apply sunscreen with a sun protection factor (SPF) of at least 15 and reapply it every two hours when outdoors, even on cloudy days. Always wear protective clothing including a hat and sunglasses, and enjoy the shade whenever possible.

World Wide Web Resources

Your American Cancer Society

www.ca.cancer.org/

The American Cancer Society is always a reliable resource for information on all types of cancer, including skin cancer.

Skin Cancer Fact Sheet

www.asds-net.org/scfactsheet.html

For basic, quick information on skin cancer, the American Society For Dermatologic Surgery provides this fact sheet on skin cancer.

Preventing Skin Cancer

www.ama-assn.org/insight/yourhlth/skin_ca/index.htm

This site, by the American Medical Association, allows you to take an on-line quiz to assess your personal risk factors for skin cancer.

Dr. Scott Gibbs is a Cape Girardeau neurosurgeon and editor-in-chief of Mosby's Medical Surfari. You may e-mail questions to him at drgibbs@semissourian.com or write in care of the Southeast Missourian, P.O. Box 699, Cape Girardeau, Mo., 63702-0699.