Dr. Friedman is Associate Professor of Dermatology, Residency Program Director, and Director of Translational Research at the George Washington School of Medicine and Health Sciences, Washington, DC.
Dr. Friedman reports no conflicts of interest in relation to this post.
Dermatologists have become accustomed to reading about the associations of dermatologic disease with extracutaneous comorbidities (psoriasis certainly takes the lead). One may see the headline “Study finds increased risk for melanoma in female acne patients” and say “Sure, why not?” However, before we all jump on the association bandwagon, let’s better appreciate this finding.
A study published online January 8 in Cancer by Zhang et al followed 99,128 female nurses in the Nurses’ Health Study II cohort for 20 years. This cohort has been utilized for numerous prospective studies over the year. Even after adjusting for known risk factors, investigators discovered that women with a history of severe cystic teenage acne had a hazard ratio of 1.44 for melanoma. The authors replicated the association with an independent melanoma case-control study of 930 cases and 1026 controls, finding an odds ratio of 1.27. They also found that individuals with teenage acne were more likely to have nevi (52.7% vs 50.1% in the cohort study; 55.2% vs 45.1% in the control study).
These data points ultimately led the team to conclude that acne may serve as an independent risk factor for melanoma, attributing androgens in female acne as a possible and plausible explanation due to their known effect on telomere elongation; melanocytes with longer telomere lengths have more opportunity to develop mutations, which could lead to malignant transformation, as the extended length ultimately delays initiation of cellular senescence. The longer these cells are “awake,” more moles can form, which means more room for trouble.
What’s the issue?
The size of this cohort certainly gives credibility to the data and statistics presented. Although the study is powered very well by the numbers, it is a unique cohort because all participants were nurses, narrowing down the demographics to some degree given general patterns, behaviors, and backgrounds when it comes to this group, an issue that has been previously raised with using this cohort. That said, more research is certainly warranted to elucidate the proposed mechanism and further clarify the association.
From a purely clinical standpoint, this paper is powerful ammo that can be used in our war against skin cancer. This very large cohort probably does not follow the American Academy of Dermatology guidelines for sun protection, skin cancer prevention, and surveillance. It could be a nice tidbit for patients at the end of your spiel on acne and then work in the photoprotection discussion, something we haven’t been the best at according to a recent study published in JAMA Dermatology (JAMA Dermatol. 2014;150:51-55)! Would it be such a bad thing if this paper helped us encourage all women with moderate to severe acne to undertake more effective sun-safe behaviors and to visit their dermatologist every year for total-body skin examinations?