The U.S. Preventive Services Task Force says there is "adequate evidence" that such counseling, which includes warning youth against increasingly-popular indoor tanning, can promote safe-sun behavior, with no serious potential harms.

"There were a number of different approaches to doing this, but all of them were focused on helping young people understand that exposure to sun and to indoor tanning -- all of the things that kids would do to get tanned -- actually result in skin damage that makes your skin ugly," said Dr. Virginia Moyer, chair of the task force from Baylor College of Medicine in Houston.

On the other hand, teens might not respond to messages about sun protection that warn of long-term cancer risks, Moyer said.

"Ugly skin is part of the pathway that eventually leads to the cancer," she told Reuters Health. "In a way we're asking them to stop it in its tracks."

Skin cancer is the most common form of cancer in the U.S. Although most cases are less-deadly forms called basal cell cancer or squamous cell cancer, the number of dangerous melanomas has been increasing -- to about 70,000 in 2011, Moyer and her colleagues reported Monday in the Annals of Internal Medicine.

Making sun-safe behavioral changes at a young age, the researchers said, can cut down on the risk of skin cancer later in life.

There's less evidence that counseling adults age 25 and older can make a difference in terms of decreasing their risk for skin cancer, the task force wrote -- so it couldn't make a recommendation for or against those doctor-patient conversations.

Sun-related counseling "takes up time and there are other things that we know are beneficial and we don't want to waste time on things that we don't know about," Moyer said.

But that doesn't mean doctors shouldn't discuss sunscreen and tanning if a patient brings it up, she added.

THE CASE FOR FULL-BODY SCREENING

In 2009 guidelines, the USPSTF said there's not enough evidence to determine the balance of benefits and harms tied to doing full-body exams to check for signs of skin cancer in adults.

But a recent study from Germany found that when one region made that type of screening available, deaths from skin cancer dropped by close to 50 percent -- to one melanoma death or fewer per every 100,000 people each year. Rates in neighboring regions that didn't do screening remained the same over time.

The screening program was started for adults in Schleswig-Holstein in 2003 and 2004, and has since been rolled out to all of Germany, with research continuing on its effect on death rates.

The findings can't prove the screening itself saved lives, researchers wrote in the journal Cancer. Starting the screening program ushered in new awareness about skin cancer that could have led people to change their sun-related behavior.

Still, Dr. Alexander Katalinic, of University Hospital Schleswig-Holstein in Luebeck, and his colleagues concluded, "the evidence is now strong enough to support the efficacy of screening programs for melanoma (with their associated professional training, publicity, and education) as a means to reduce melanoma mortality."

Germany is the only country that has implemented full-body skin cancer screening, Katalinic said, and screening there is covered by insurance. Under the screening program, each check for skin cancer lesions costs 21 Euros (about $27), and can be done every other year.

"Primary prevention (such as behavioral counseling) is not enough," Katalinic told Reuters Health. "I think screening has the potential to save lives."

The USPSTF will be due to review the evidence of harms and benefits of full-body screening within a few years. As with any screening program, the harms of checking for signs of skin cancer include diagnosing and treating people who never would have developed full-fledged, symptomatic cancer.

Katalinic said that one of the ways to refine the screening process is to figure out who is most at risk for melanoma and screen them frequently and lower-risk people less often.

SOURCES: bit.ly/atTzv0 Annals of Internal Medicine, online May 7, 2012 and Cancer, online April 19, 2012.

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