Sunshine makes flowers and skin cancer grow

By Amy Bertrand
Knight-Ridder News Service

Skin cancer is the fastest-growing cancer in the United States. One in five Americans will develop some form of skin cancer during their lifetime. More than 1 million new cases of skin cancer will be diagnosed this year, more than all other cancers combined, according to the American Cancer Society. That figure includes diagnoses of the most common and most curable types of skin cancer (basal cell and squamous cell) and the sometimes deadly melanoma.

"A tan is not healthy," says Dr. Scott Fosko, chairman of dermatology at St. Louis University School of Medicine. A "healthy tan" is "almost an oxymoron, because a tan is a body's reaction to the damage from the sunlight. It represents damage to skin, and one outcome is skin cancer."

Studies have shown that in 10 percent of patients, there is a genetic predisposition for skin cancer which can affect people of all skin colors.

"People of color can get melanoma on palms and soles," says Dr. Lynn Cornelius, head of dermatology at Washington University in St. Louis and a member of the Siteman Cancer Center at Barnes-Jewish Hospital. "They are at a lower risk, but it still can occur."

In the majority of cases, we know the cause — excessive sun exposure.

Unfortunately, a lot of the damage is done while we are children. Even a single blistering sunburn in adolescence doubles the risk of developing malignant melanoma later in life, says Arthur Sober, a melanoma expert from Massachusetts General Hospital. Cornelius doesn't like to go that far, but she does say, "Intermittent sunburns early in life do raise your risk of melanoma."

But the good news is that skin cancer is the most preventable type of cancer, and there are things you can do now to lower your risks:

Shield your skin

Wear sunscreen: Sunlight has two types of harmful rays — UVA rays and UVB rays. The UVB rays are the sun's burning rays (which are blocked by window glass) and are the primary cause of sunburn and skin cancer. UVA rays (which pass through window glass) penetrate deeper into the dermis, or base layer of the skin. Make sure your sunscreen offers protection against both. Lather sunscreen on at least 30 minutes before you head outside, then reapply every 90 minutes. Doctors recommend you use a sunscreen with an SPF of at least 30. Also consider using lip protection that has sunscreen. People with light or thin hair can use a spray sunscreen on their scalp. Sunscreen-protective shampoos will help keep your hair from getting brittle, but won't protect your scalp against skin cancer.

Wear protective clothing: A hat with a wide brim and long-sleeved clothing is recommended. Several manufacturers offer clothing that blocks ultraviolet rays. To protect your eyes, wear sunglasses with a label that says they block 99 percent of UV rays. Also note that, though many parents put a T-shirt on their children to keep them from getting a sunburn at the pool, once that shirt gets wet, it loses its protection.

Limit exposure

Get a shade for your car window: SLU's Fosko says he sees more cases of actinic kerotoses, which are precancerous skin lesions, on the left side of the face and forehead than on the right side.

The reason could be the time you spend in your car during your daily commute. "Even if you only have a short commute, that exposure has a cumulative effect that builds up over many years," says Fosko.

Stay out of the sun: Avoid outdoor activities between 10 a.m. and 4 p.m., when the sun's rays are the strongest, and seek shade whenever possible. Follow the shadow rule — if your shadow is shorter than you are, the sun's damaging rays are at their strongest and you are more likely to sunburn.

Beware of reflective surfaces: Sand, snow, concrete and water can reflect more than half the sun's rays onto your skin, so sitting in the shade does not guarantee protection from the sunburn.

Skin deep

Avoid tanning beds: By age 17 nearly 40 percent of girls have used a tanning bed, says the Skin Cancer Foundation. Many teens believe a tan is worth the risk.

Opt instead for sunless tanning lotions and the new sunless tanning spray booths available at many tanning salons. But beware of "tanning pills" — their main ingredient, canthaxanthin, can cause serious side effects.

Do self-screenings: Doctors recommend you check your skin once a month to see if there are any changes in moles. Use a mirror for places you can't see. And check your scalp. Fosko says he often sees cases where a hairstylist or barber was the first to notice a problem. Report any changes to your doctor immediately.

Talk to the pros

Visit your dermatologist.

Don't wait if you see something that looks suspicious on your skin. Even if you don't see a spot that's suspect, it doesn't hurt to visit your dermatologist once a year, especially if you are at risk for skin cancer.

If your doctor should find something, he or she will often take a team approach to your care. At the Siteman Cancer Center, "we have a multidisciplinary approach to melanoma," says Cornelius. "Dermatologists work with a medical oncologist and plastic surgeons and other disciplines. We see patients together so we can talk about patients from the standpoint of care."

Teach children sun protection early: Sun damage occurs with each unprotected sun exposure and accumulates over a lifetime. .

Up to 80 percent of sun damage occurs by the time we are 18. So now, as many hit middle age, they are seeing the effects of a lifetime of sun damage, whether that's in the form of precancerous cells, cancer or just wrinkles.

Damage control

Other than staying sun-smart now, what can we do to counteract the sun's damage?

"It's been shown that continued sun protection can help in decreasing the melanoma risk," says Cornelius.

Recent research has suggested that applying DNA repair enzymes to the skin in lab tests can help counteract damage. Retinoids (such as Retin-A) may temporarily prevent the development of nonmelanoma skin cancers. The research on these methods is not definitive, Cornelius says.

She also says that treating a sunburn by methods available today doesn't really help reduce the skin damage. "It's just symptomatic care with topical medication that can help reduce the discomfort." Using over-the-counter pain medication, aloe vera and cool compresses is recommended.

Wizened wisdom

And if the warnings about skin cancer aren't enough to get you to stay sun smart, consider how you'll look in 30 years.

"Basically, wrinkles are not a reflection of age," Fosko says. "They're a reflection of the amount of radiation damage. Some people who are 75 look like they're 35. When you get sun over many years you get the damage. The skin sags and loses elasticity. The great majority is from the sun."