Risk of lymphoma in patients with atopic dermatitis and the role of topical treatment: A systematic review and meta-analysis

Background: There is controversy regarding a potential increased risk of lymphoma in patients with atopic dermatitis (AD). Objective: To assess the risk of lymphoma and the role of topical treatments in patients with AD. Methods: A systematic literature search and a separate meta-analysis were performed on case control and cohort studies. Results: Of the 3979 articles retrieved, 24 references met the inclusion criteria. In cohort studies, the risk of lymphoma was slightly increased, with a relative risk (RR) of 1.43 (95% confidence interval [CI], 1.12-1.81). In case control studies, no significant increased risk of lymphoma was found, with an odds ratio (OR) of 1.18 (95% CI, 0.94-1.47). Severity of AD was a significant risk factor. Highly potent topical steroids were associated with an increased risk of lymphoma. For topical calcineurin inhibitors (TCIs), a significant association between tacrolimus and mostly skin lymphoma was found in 1 study. Limitations: Confusion between severe AD and cutaneous T-cell lymphoma may account for part of the increased risk of lymphoma in patients with AD. Conclusion: This systematic literature review shows a slightly increased risk of lymphoma in patients with AD. Severity of AD appears to be a significant risk factor. The role of topical steroids and TCIs is unlikely to be significant.