Ovarian cancer and smoking: Individual participant meta-analysis including 28 114 women with ovarian cancer from 51 epidemiological studies

Abstract

Background Smoking has been linked to mucinous ovarian cancer, but its eff ects on other ovarian cancer subtypes and on overall ovarian cancer risk are unclear, and the fi ndings from most studies with relevant data are unpublished. To assess these associations, we review the published and unpublished evidence. Methods Eligible epidemiological studies were identifi ed by electronic searches, review articles, and discussions with colleagues. Individual participant data for 28 114 women with and 94 942 without ovarian cancer from 51 epidemiological studies were analysed centrally, yielding adjusted relative risks (RRs) of ovarian cancer in smokers compared with never smokers. Findings After exclusion of studies with hospital controls, in which smoking could have aff ected recruitment, overall ovarian cancer incidence was only slightly increased in current smokers compared with women who had never smoked (RR 1.06, 95% CI 1.01-1.11, p=0.01). Of 17 641 epithelial cancers with specifi ed his