Abstract: Objective Exploring the relationship between gender differences in breast cancer survival outcomes and tumor subtypes by conducting the largest population-based comparative study of men with breast cancer and women with breast cancer.Methods A population-based retrospective cohort study using data from the US disease surveillance,epidemiology and final outcomes(Seer) Project 2010-2012,to investigate differences in tumor subtypes,overall survival(OS),and breast cancer-specific mortality(BCSM) between men and women.〖WTHZ〗Results〓〖WTBZ〗A total of 181814 breast cancer patients(1516 men and 180298 women) met the criteria of this study.The male patients were mostly black people,old,with low histological grade,late stage,large tumor,more lymph node and distant metastasis,and human EGFR 2(HER2) negative tumor(P<0.05).The two year OS of male and female patients was 91.2% and 93.7%,and that of BCSM was 2.2% and 2.5%,respectively.Univariate analysis showed that the OS of male triple negative(TN),hormone receptor(Hor)/HER2 positive and HOR/HER2 negative patients were worse(P<0.01).At the same time,both HOR/HER2 positive and TN subtype were significantly associated with BCSM in male patients(P<0.01).Multivariate analysis showed that OS and BCSM were worse in patients with TN MBC(P<0.05).At the same time,the results showed that male patients in the HR +/HER2 negative subgroup were less likely to die of BC after adjustment for other factors(P<0.05).Conclusion A 2year OS and BCSM analysis of breast cancer subtypes showed significant differences between male and female breast cancer patients with TN subtypes,and these differences deserve further study.

Key words: breast cancer, survival outcome, sex difference, tumor subtype