Too Much Sun Increases Risk Of Melanoma

Summer is a time to sport shorts, tees and tanks; play outside or hit the beach.

There's lots of fun to be had in the sun. But too much sun exposure can increase your risk of developing melanoma.

The deadliest form of skin cancer, melanoma begins in the melanocytes, the melanin-producing cells located in the bottom layer of the epidermis. Melanomas can develop anywhere on the skin, including the neck and face; they typically start to form on the trunk (chest and back) in men and on the legs in women. The risk for melanoma increases as people age, but the condition isn't uncommon in people under 30. Recent medical studies suggest that some people with melanoma have an early history, going back to childhood, of sunburns or other intense exposure to ultraviolet (UV) rays. 

Melanoma tumors look like moles. Because melanoma cells can still make melanin, the tumors are usually brown or black. In cases where melanoma cells don't make melanin, tumors can appear pink, tan, skin-colored, red or white. Melanoma is more common in Caucasians than African Americans, though African Americans are susceptible to developing melanoma on the palms of their hands, soles of their feet, and under their nails.

In addition to UV radiation from sunlight, exposure to tanning beds and sun lamps, atypical moles, the presence of multiple moles, and a weakened immune system are among risk factors for melanoma. Even family history can play a role. But overexposure to sunlight, the main source of UV rays, stands out as the most serious risk factor.

UV rays are strongest during the summer, at high altitudes, near the equator and at midday. You should use precaution even on days when it isn't sunny out, says Dr. Arun A. Mavanur, a board-certified surgeon at LifeBridge Health who specializes in surgical oncology (cancer surgery).

"It isn't just exposure to direct sunlight that increases melanoma risk. It's the ultraviolet rays. On a cloudy day, you still have UV light. You may not have sunlight, but you have UV light," Mavanur said.

Because skin damage can still occur on cloudy or overcast days, Mavanur says, sun safety "has to become a year-round habit." He says people should apply a thick layer of broad-spectrum sunscreen (which can protect the skin from both UVA and UVB rays) with an SPF (sun protection factor) of 15 or higher at least 15 minutes before going outside. (You should reapply sunscreen every two hours or after swimming, sweating or drying yourself with a towel.) It's also important to wear sunglasses and a hat with a wide brim to protect your face and eyes.

Regarding clothing, long-sleeve shirts, pants and long skirts provide more protection from sunlight. Dark colors, because they can more effectively absorb UV rays, provide more protection than light-colored clothing. It's harder for UV rays to penetrate clothing with tightly woven fabric than loosely woven clothing. Also, dry fabric offers more protection than wet fabric.

Seek shade whenever possible. The Centers for Disease Control and Prevention (CDC) says avoiding the sun from 10 a.m. to 4 p.m. March through October and from 9 a.m. to 3 p.m., when the presence of UV light is strongest, is ideal.

Melanoma is among the conditions treated by medical oncologists at LifeBridge Health. To schedule an appointment with one of our highly trained physicians and find out why LifeBridge Health is Baltimore's premier health care organization, fill out our online appointment request form, or call 410-601-WELL. Click here to learn more about ongoing melanoma clinical trials. You can learn more about melanoma, including possible treatment options, by clicking here.