Personal history of rosacea and risk of incident cancer among women in the US

BACKGROUND: Rosacea is an inflammatory skin disease. We examined the association between personal history of rosacea and risk of incident cancers. METHODS: A total of 75 088 whites were included from the Nurses' Health Study II (1991–2011). Information on clinician-diagnosed rosacea and diagnosis year was collected in 2005. All cancers other than basal cell carcinoma (BCC) were confirmed. RESULTS: During 1 447 205 person-years, we identified 5194 cases with internal malignancies and 5788 with skin cancers. We did not observe significant associations between personal history of rosacea and internal malignancies, except for thyroid cancer (hazard ratio (HR)=1.59, 95% confidence interval (CI)=1.07–2.36). Among skin cancers, personal history of rosacea was associated with an elevated risk of BCC (HR=1.50, 95% CI=1.35–1.67). CONCLUSIONS: We suggest possible associations between personal history of rosacea and an increased risk of thyroid cancer and BCC. Further studies are warranted to replicate our findings and to explore the underlying mechanisms.