USPSTF finds insufficient evidence in favor of screening for skin cancer

There is not sufficient evidence to recommend visual skin examination by a clinician in screening for skin cancer in asymptomatic adults, the U.S. Preventive Services Task Force concluded after a systematic review of available clinical trials.

Despite the lack of evidence, researchers stressed the need for skin cancer prevention and high-quality clinical trials to provide more information on screening.

The agency noted that it "prioritized outcomes related to melanoma in developing this recommendation statement."

"Skin cancer includes melanoma and basal and squamous cell carcinoma," the task force wrote in JAMA. "Basal and squamous cell carcinoma, known together as nonmelanoma skin cancer, are the most common types of cancer in the Unites States and represent the vast majority of all cases of skin cancer (> 98%). However, nonmelanoma skin cancer rarely results in death or substantial morbidity (< 0.1% of patient deaths are caused by this type of cancer), whereas melanoma skin cancer has notably higher mortality rates."

The USPSTF statement, an update from recommendations issued in 2009 that also found insufficient evidence, stated that there was no evidence to conclude that screening reduced skin cancer morbidity or mortality.

The review included 13 "fair- or good-quality" studies that were reported in 15 publications; none were randomized clinical trials, according to Karen J. Wernli, PhD, MS, from the Group Health Research Institute at Kaiser Permanente Research Affiliates and lead author of the review.

"Only limited evidence was identified for skin cancer screening, particularly regarding potential benefit of skin cancer screening on melanoma mortality," they concluded. "Future research on skin cancer screening should focus on evaluating the effectiveness of targeted screening in those considered to be at higher risk for skin cancer."

The recommendation statement echoed their findings.

"Several comments suggested that the USPSTF should consider making a separate positive recommendation for persons who are at increased risk for skin cancer (eg, those with a family history of melanoma), as they may potentially benefit more from a screening intervention," the agency wrote. "At present, there is insufficient evidence for any population that regular visual skin examination by a clinician can reduce skin cancer-related morbidity and mortality; the USPSTF agrees that targeted research among populations with the highest burden of disease would be useful."

The USPSTF noted that many medical organizations, such as the American College of Physicians, American College of Preventive Medicine and the American Academy of Dermatology, have not issued recommendations regarding skin cancer screening. The American Academy of Family Physicians also reported insufficient evidence and the American Cancer Society recommended a skin exam for adults 20 years and older.

In an accompanying editorial published in JAMA Internal Medicine, Eleni Linos, MD, PhD, from the department of dermatology from the University of California, San Francisco, and colleagues wrote that the ruling will likely leave national organizations disappointed and patients and physicians confused.

"However, the USPSTF recommendations are based on a rigorous evidence review that balanced the benefits and risks of screening," they wrote. "The potential benefits are apparent, but the risks, such as unnecessary procedures and their downstream complications, may not be. Overtreatment of skin cancer may be especially problematic for patients with limited life expectancy due to old age or comorbidities. These patients may not live long enough to benefit from more intensive treatments but may be at risk for short-term treatment-related complications."

Linos and colleagues also stressed that the recommendations are not downplaying the importance of skin cancer.

"Instead, the report should motivate us to improve the evidence base for identifying groups of people in whom the benefits of screening might outweigh risks," they concluded. "We need high-quality, long-term randomized clinical trials of the effectiveness of screening on skin cancer prevention. Meanwhile, we should also fully implement skin cancer primary prevention by eliminating indoor tanning exposure, especially among youths, and increasing the use of sun-protection strategies that work." – by Chelsea Frajerman Pardes

References:

Linos E, et al. JAMA Intern Med. 2016;doi:10.1001/jamainternmed.2016.5008.
USPSTF. JAMA. 2016;doi:10.1001/jama.2016.8465.
Wernli KJ, et al. JAMA. 2016;doi:10.1001/jama.2016.5415.

Disclosures: The researchers report no relevant financial disclosures.