Adjuvant Endocrine Therapy for Estrogen Receptor-beta Positive Triple Negative Breast Cancer

The study is a prospective multi-center randomized control clinical trial which is sponsored by the researchers. The purpose of this study is to determine the effectiveness of adjuvant endocrine therapy for operable ER-beta positive, ER-alpha/PR negative, Her-2 negative breast cancer(triple negative breast cancer, TNBC) patients. The ER-beta positive TNBC patients who had undergone modified radical mastectomy or breast-conserving surgery were randomly (1:1) enrolled to receive toremifene (60 mg per day for premenopausal and perimenopausal patients) /anastrozole(1mg per day for postmenopausal patients) or observation within 4 weeks after adjuvant chemotherapy and/or radiation therapy if necessary.The follow-up time will be at least five years. The disease free survival(DFS) and overall survival(OS) between endocrine group and observation group will be compared to evaluate the effectiveness.