Review of evidence
The USPSTF commissioned a systematic review to evaluate the benefits and harms of screening for skin cancer in asymptomatic adolescents and adults, including evidence for both keratinocyte carcinoma (basal cell carcinoma and squamous cell carcinoma) and cutaneous melanoma.
Foundational evidence showed that the sensitivity of visual skin examination by a clinician to detect melanoma ranged from 40% to 70% and specificity ranged from 86% to 98%. Evidence that evaluated the diagnostic accuracy of visual skin examination to detect keratinocyte carcinoma was limited and inconsistent. There were no new studies reporting on diagnostic accuracy for an asymptomatic screening population.
The USPSTF also reviewed 20 studies in 29 articles (n = 6,053,411). This included three nonrandomized studies evaluating two skin cancer screening programs in Germany, but results were inconsistent. In addition, the ecological and nonrandomized design of the studies limited the conclusions that could be drawn and the applicability to a U.S. population was difficult to assess because of differences in population diversity and health care delivery in the United States.
Other nonrandomized studies that looked at various outcomes, such as harms and stage at diagnosis and melanoma or all-cause mortality, also did not provide sufficient evidence to support screening.
Research is needed
In a second accompanying editorial published in JAMA Dermatology, Adewole S. Adamson, MD, MPP, of the division of dermatology and dermatologic surgery at the University of Texas, Austin, pointed out that unlike other cancer screening programs, such as those for breast, colon, and prostate cancer, skin cancer screening programs are somewhat less organized.
Dr. Adewole "Ade" Adamson
The other programs focus on defined groups of the population, generally with easily identifiable characteristics such as age, sex, and family history, and importantly, there are always defined ages for initiation and halting of screening and intervals for screening frequency. None of these basic screening parameters have been widely adopted among dermatologists in the United States, he wrote. “One important reason why skin cancer screening has remained inconsistent is that it is not covered by Medicare or by many commercial insurance companies,” Dr. Adamson told this news organization. “The test, in this case the skin exam, is often performed as part of a routine dermatology visit.”
Dermatologists should take the lead on this, he said. “Dermatologists should push for a high quality prospective clinical trial of skin cancer screening, preferably in a high-risk population.”
Dr. Donahue agrees that research is needed, as noted in the recommendation. For example, studies are needed demonstrating consistent data of the effects of screening on morbidity and mortality or early detection of skin cancer, and clearer descriptions of skin color and inclusion of a full spectrum of skin colors in study participants. Clinical research is also needed on outcomes in participants that reflect the diversity of the U.S. population.
“I hope funding agencies will be interested in this area of study,” she said. “We put out the whole systematic review and point out the gaps. We need consistent evidence in detecting cancer early and reducing complications from skin cancer.”
The U.S. Congress mandates that the Agency for Healthcare Research and Quality support the operations of the USPSTF.
None of the USPSTF authors report any disclosures. Dr. Asgari reported receiving royalties from UpToDate. Dr. Crane did not make any disclosures. Dr. Adamson reported serving as an expert reviewer for the U.S. Preventive Services Task Force skin cancer screening report, as well as support from the Robert Wood Johnson Foundation, the Dermatology Foundation Public Health Career Development Award, the National Institutes of Health, the American Cancer Society, and Meredith’s Mission for Melanoma.
A version of this article originally appeared on Medscape.com.