Association between atopic dermatitis and squamous cell carcinoma: a case–control study.

Abstract: Background: Conflicting data have been published on whether an association exists between atopic dermatitis (AD) and nonmelanoma skin cancer. This study aimed to determine whether individuals with AD had an increased risk of squamous cell carcinoma (SCC) development. Methods: We conducted a retrospective, case–control study of patients residing in Olmsted County, Minnesota. Cases were selected from patients seen at Mayo Clinic (Rochester, Minnesota) who had an initial SCC diagnosis (either invasive SCC or SCC <italic>in situ</italic>) from January 1, 1996, through December 23, 2010. Age‐ and sex‐matched controls were selected from patients seen at Mayo Clinic with no history of SCC before the case event date. Results: Three hundred ninety‐nine individuals with a documented history of SCC were identified and matched with 780 controls who did not have a history of SCC. After adjusting for race, smoking history, ionizing radiation exposure, corticosteroid and cyclosporine use, and non‐SCC skin cancers, the odds ratio for SCC development between patients with history of AD versus patients without history of AD was 1.75 (95% CI, 1.05–2.93). Conclusions: Our findings support an increased risk of SCC development in the setting of AD. [ABSTRACT FROM AUTHOR]