No increased skin cancer risk with topical immunosuppressant ointments, study finds

BOSTON – Adults with the chronic skin condition atopic dermatitis can rest easy in the knowledge that two topical immunosuppressant medications commonly prescribed to treat the condition do not appear to increase the risk for the most common forms of skin cancer, despite package label warnings to the contrary, researchers from Massachusetts General Hospital (MGH) found.

Looking at data on nearly 94,000 people diagnosed with dermatitis in general or more specifically atopic dermatitis –– Maryam M. Asgari, MD, MPH, investigator in the Department of Dermatology at MGH and colleagues found that patients who were prescribed topical tacrolimus or pimecrolimus did not have a greater risk for either basal cell or squamous cell carcinomas compared with patients who received prescription topical corticosteroids, the most common topical treatment for dermatitis.

Their findings are published online in JAMA Dermatology.

Tacrolimus and pimecrolimus belong to a class of drugs known as topical calcineurin inhibitors (TCI). The US Food and Drug Administration (FDA) requires that TCI medications carry a “black box” warning about increased risk for skin cancer, although previously published studies have shown conflicting results regarding the use of TCIs and skin cancer risk. The FDA has mandated long-term studies of patients with atopic dermatitis who use these products to get a better handle on their potential for increasing skin cancer risk.

“I thought that the data implicating increased skin cancer risk with TCIs was not robust, and that prompted me to get involved in studying it ” Asgari said.

The MGH researchers took advantage of the comprehensive database maintained by Kaiser Permanente Northern California in Oakland, which contains integrated pharmacy and pathology data on 93,746 adults age 40 and older who were diagnosed by a clinician with atopic dermatitis or dermatitis from January 2002 through December 2013. 

Since nearly all Kaiser Permanente patients use the health plan’s pharmacy, Asgari and colleagues were able to determine the proportions of patients who received prescriptions for TCIs vs. topical corticosteroids, and then compared those data with pathology-verified skin cancer diagnoses.

They found that there was no association between TCI use and risk for either keratinocyte carcinomas overall, or for squamous cell or basal cell carcinomas individually. Looking at different doses, frequency, and duration of TCI use did not change the findings.

“We analyzed the data with multiple sensitivity analyses to explore the association of TCI use and skin cancer risk in detail, which revealed no association each time, so that was very reassuring” Asgari says.

Asgari’s co-investigators include Ai-Lin Tsai, MA, Lyndsay Avalos, PhD, MPH, Monica Sokil, BS, and  Charles P. Quesenberry Jr, PhD, all of Kaiser Permanente Northern  California. The study was supported by a grant to Kaiser Permanente from Valeant Pharmaceuticals. Asgari disclosed receiving grants from Valeant during the conduct of the study.

About the Massachusetts General Hospital
Massachusetts General Hospital, founded in 1811, is the original and largest teaching hospital of Harvard Medical School. The MGH Research Institute conducts the largest hospital-based research program in the nation, with an annual research budget of more than $1 billion and comprises more than 8,500 researchers working across more than 30 institutes, centers and departments. In August 2020 the MGH was named #6 in the nation by U.S. News & World Report in its list of "America’s Best Hospitals."