RESEARCH ARTICLE The CYP19 RS4646 Polymorphism Is Related to the Prognosis of Stage I–II and Operable Stage III Breast Cancer

Purpose Aromatase, encoded by the CYP19 gene, catalyzes the final step of the conversion of an-drogens to estrogens. Given the critical role of CYP19 in estrogen synthesis, the potential in-fluence of CYP19 rs4646 polymorphism on breast cancer survival, deserves further study. Methods Genotyping for CYP19 rs4646 variants was performed on 406 Chinese women with stage I–II and operable stage III breast cancer. Associations were evaluated between CYP19 rs4646 genotypes and disease-free survival (DFS). Results In premenopausal patients, women who are homozygous for the minor allele (AA) have a longer DFS compared with those carrying the major allele (CC or AC) (87 months versus 48.7 months; Hazard ratio (HR) = 0.56, 95 % CI = 0.318-0.985, P = 0.041). These differ-ences were further demonstrated by a multivariate analysis (HR = 0.456, 95 % CI = 0.249-0.836, P = 0.011). Conversely, the same variant (AA) was estimated to be associated with a poorer DFS in postmenopausal women (AA versus AC or CC: 13.7 months versus 56.3 months; HR = 2.758, 95 % CI = 1.432-5.313, P = 0.002). Furthermore, the differences were confirmed by the COX proportional hazards model (HR = 2.983, 95 % CI =1.494-5.955, P