The researchers noted that the inclusion of siblings in the study suggests that sun exposure in childhood was not a confounding factor. Presumably, they wrote, the siblings had similar levels of exposure as children, although exposure to sun bed tanning could differ between siblings.
“Study methods appear very strong and consistent with other work done in the area,” Dr. Silverberg said in the interview. As for possible causes of the disparities, he noted that exposure to the sun or to tanning beds could explain the greater risk of BCC among men who have sex with men. “For SCC, there may be a biological link, as studies have suggested a link with human papillomavirus for that particular cancer,” he added.
No study funding was reported. The study authors reported disclosures that included grants, research grants, speaker fees, and/or advisory board honoraria from several drug manufacturers. Dr. Silverberg has no relevant disclosures.