Should You Get Screened for Skin Cancer?

Every summer as Americans slather on sun lotion, they are reminded of the dangers of skin cancer.

This year alone, more than 76,000 people in the United States will develop melanoma, the deadliest form of the disease, and about 10,000 will die from it.

The U.S. Preventive Services Task Force said on Tuesday, however, that there still isn’t enough evidence to recommend total-body screenings and declined to take a position on the practice.

In short, the 17-member independent panel said that it could not determine — after reviewing thousands of research papers and studies from around the world — whether the benefits of screening outweighed the potential for harm if unnecessary or excessive procedures were performed.

One particular study that the task force relied upon concluded that full-body screenings only reduced deaths from melanoma by one death per 100,000 people screened.

Published in the journal JAMA, the statement by the task force essentially reiterates the position it took in 2009 and has reignited debate on the issue at the height of the summer season.

To decide whether you should get screened, here are some guideposts on skin cancer research and the views of some experts.

What is skin cancer?

There are three types: squamous cell carcinoma, basal cell carcinoma and melanoma. Squamous and basal are grouped together into nonmelanoma skin cancers and are by far the most prevalent form of the disease, making up about 98 percent of cases. They are also rarely fatal, making up only about 0.1 percent of skin cancer deaths.

Melanoma poses a much bigger threat. In 2015, there were 73,870 diagnoses and 9,940 deaths in the United States.

Who is most at risk?

Those who have had melanoma, or who have a family history of the disease, and people who have more than 100 moles on their bodies are most likely to develop the disease. The task force did not include this high-risk group in its study.

White men 65 and older are at higher risk than the rest of the general population. People with light skin are also more prone to developing skin cancer than people of color, though they too can get melanoma.

What do doctors look for in a screening?

There are the A B C D E’s to identify potentially troublesome skin lesions: asymmetrical, when one half doesn’t match the other; borders of the lesion that look uneven or ragged; colors that differ from one another; diameter larger than 6 millimeters, about the size of a pencil eraser; evolving lesions over time.

What is the Preventive Services Task Force?

Members of the United States Preventive Services Task Force are appointed by the Department of Health and Human Services. The 16-member panel of preventive medicine and epidemiology experts is independent of the federal agency, and advises medical professionals on screenings.

What did the task force find?

For patients without signs or symptoms of skin cancer, the task force decided there was insufficient evidence to make recommendations either for or against skin examinations by clinicians.

The statement also relied heavily on a large German study that found that skin cancer screenings decreased melanoma deaths in the region by only about one death per 100,000 people screened.

Dr. Michael Pignone, a member of the task force, said that he was frustrated that the task force couldn’t offer more definitive guidance. “But I feel good that we can’t overstate what we know and what we don’t know,” he added.

Dr. Hensin Tsao from Massachusetts General Hospital, who wrote an editorial that accompanied the task force’s statement, cautioned that patients and doctors should not over-interpret the task force’s decision. “It is important to note that ‘insufficient evidence’ does not translate to ‘evidence of inadequacy,’ ” he said.

Why didn’t the task force provide concrete guidance?

“What we’re lacking is a high-quality study that would tell us what the reduction in death from skin cancer, specifically melanoma, would be,” Dr. Pignone said. “We just don’t have that large-scale randomized trial of screening versus no screening to give us a good sense of the reduction that comes from screening.”

How can a screening be harmful?

The task force identifies three potential problems: scarring, misdiagnosis and overdiagnosis. Cosmetic damage caused by repeated biopsies can lead to scarring, according to Dr. Pignone. Although there are no hard numbers to support an increase in misdiagnosis and overdiagnosis, the potential for unnecessary treatment could be classified as a harm.

“These are small, slow- or not-growing melanomas that if they were not ever found they wouldn’t have caused any problem in a person’s lifetime,” Dr. Pignone said. “Instead we find them in screenings, and a person has to undergo a more extreme type of treatment that gives them no benefit because that melanoma wouldn’t have caused any harm.”

But not everyone agrees with the task force.

“It’s a travesty to suggest that the harm from a little biopsy would outweigh the benefit of finding a melanoma early,” said Dr. Deborah Sarnoff, a dermatologist and senior vice president of the Skin Cancer Foundation, a nonprofit organization. “I would hate for someone to read it and not get something checked because there is ‘insufficient evidence’ — It doesn’t come with a billboard saying ‘I am melanocarcinoma.’ ”

What do doctors advise?

“The best recommendation at this point is to talk to your doctor and decide together what to do,” Dr. Pignone said.

The American College of Physicians and the American College of Preventive Medicine do not have any current recommendations on skin cancer screenings. The American Academy of Family Physicians, like the task force, concluded there was not enough evidence to provide a recommendation on the benefits and harms. The American Cancer Society, which had earlier recommended that people 20 and older should have their skin examined as part of a regular checkup, responded to Tuesday’s news by saying that it does not advise getting annual exams.

“Dermatologists know that skin cancer screenings can save lives,” Dr. Abel Torres, president of the American Academy of Dermatology, said in a statement. “We know that screenings, which are noninvasive, quick and painless, are the best tool possible to detect skin cancer early when it is most treatable.”

“As a dermatologist I personally believe that inspection of the skin is part of a good physical exam since many skin disorders can be easily detected by simply looking,” Dr. Tsao said. “Everyone should probably have their skin examined by a physician or health care provider at some point during their early adulthood.”