Potential association between rosacea and cancer: A study in a medical center in southern China.

Growing evidence suggests that rosacea increases the risk of systemic diseases, but studies of the relationships between rosacea and cancer are rare. Aimed to assess the relationship between rosacea and cancer, a total of 7548 patients with confirmed internal malignancies and 8340 cancer-free individuals aged 18 years or more were included in this study from November 2015 to October 2017. Clinical characteristics, personal history and laboratory data were recorded when patients were diagnosed with rosacea. Logistic regression analyses were performed to analyze associations between cancer and rosacea. We found rosacea significantly affected more women than men in both cancer and cancer-free group. The data showed there was no relationship between rosacea and lung, gastrointestinal, nasopharyngeal and gynecological cancer. However, rosacea was significantly associated with the increased risk of breast cancer and glioma, but negatively associated with the risk of hematological cancer. Of the 190 female breast cancer patients with rosacea, 98.95% had the erythematotelangiectatic subtype of rosacea, 48.42% had chloasma and 76.31% of them were Fitzpatrick skin type III and IV. In our binary regression model, breast cancer patients with rosacea had a higher prevalence of estrogen receptor-positive status, lower high-density lipoprotein levels and higher low-density lipoprotein than patients with breast cancer but no rosacea. Our findings indicate that rosacea is significantly associated with higher incidence of breast cancer, glioma and lower prevalence of hematological cancer.