History of allergy and atopic dermatitis in relation to squamous cell and Basal cell carcinoma of the skin.

BACKGROUND: Little is known about whether history of allergies and atopy is related to the occurrence of keratinocyte cancers. Thus, we evaluated the association between history of allergies and atopy and the incidence of squamous cell carcinoma (SCC) and early onset basal cell carcinoma (BCC).
METHODS: As part of a population-based case-control study, interviews were conducted with 1,050 residents of New Hampshire (375 early onset BCC cases and 251 controls, 254 SCC cases and 432 controls). ORs of SCC and early onset BCC and history of allergy and atopic dermatitis were computed using logistic regression, while controlling for potential confounding factors.
RESULTS: An overall inverse association was observed between a history of allergy and early onset BCC [OR, 0.61; 95% confidence interval (CI), 0.38-0.97] but not SCC (OR, 1.18; 95% CI, 0.78-1.79). Among women, we found reduced ORs of both early onset BCC and of SCC in relation to allergy history (early onset BCC OR, 0.53; 95% CI, 0.31-0.92 and SCC OR, 0.59; 95% CI, 0.29-1.19). Among men, we observed no clear association with early onset BCC (OR, 0.87; 95% CI, 0.39-1.99) and an increased risk of SCC (OR, 1.58; 95% CI, 0.93-2.69).
CONCLUSION: Our findings suggest that allergies and atopy may influence risk of early onset BCC and SCC, and that effects may be gender specific. IMPACT: A deeper understanding of the immune mechanisms underlying allergies and atopy may provide new routes of preventing keratinocyte cancers. ©2015 American Association for Cancer Research.