Topical calcineurin inhibitors did not increase skin cancer risk in atopic dermatitis

Among a large cohort of patients with atopic dermatitis, treatment with topical calcineurin inhibitors demonstrated no association with elevated risk for keratinocyte carcinoma, according to a study.

“Topical calcineurin inhibitors (TCIs), primarily used to treat atopic dermatitis, carry a black box label warning users about the potential for increased skin cancer risk,” Maryam M. Asgari, MD, MPH, of the department of dermatology at Massachusetts General Hospital and the department of population medicine at Harvard Medical School, and colleagues wrote.

They added that the potential association between TCI therapy and risk for keratinocyte carcinoma (KC) — defined as basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) — remains poorly defined due to a lack of large-scale post-marketing surveillance studies.

The retrospective cohort included 93,746 adults aged 40 years or older who had been diagnosed with AD by a physician between Jan. 1, 2002, and Dec. 31, 2013. Eligible participants were accrued from Kaiser Permanente in Northern California. The mean age of patients in the cohort was 58.5 years, with 58.7% women.

Skin cancer outcomes were compared for patients treated with TCIs vs. topical corticosteroids. Other factors that underwent analysis included TCI dose, frequency and duration of exposure, according to the findings.

The analysis included 7,033 patients exposed to TCIs, 73,674 patients treated with topical corticosteroids and 46,141 patient who were not treated with either medication.

Results showed that there were 7,744 incident KCs overall.

Multivariate analysis results showed that TCI exposure failed to correlate with KC risk overall when compared with corticosteroid exposure (adjusted HR = 1.02; 95% CI, 0.93-1.13).

A similar outcome was reported for the association between BCC risk and TCI exposure compared with topical corticosteroid exposure (aHR = 1.01; 95% CI, 0.90-1.14). SCC risk also was not elevated in TCI exposure compared with corticosteroid exposure (aHR = 0.94; 95% CI, 0.82-1.08).

When patients exposed to TCIs were compared with patients who were exposed to neither medication, a similar outcome was reported for BCC risk (aHR = 1.04; 95% CI, 0.91-1.19).

TCI dose, frequency or duration of use failed to affect overall KC, BCC or SCC risk, according to the findings.

“These findings suggest that use of TCIs may be safe with respect to KC risk among adults with AD,” the researchers wrote.