Inclusion Criteria:  age≥18 years; Tumor that expressed ER or progesterone receptor in at least 10% of the cells, as assessed by immunohistochemical testing T1 to T3, any N, and M0, according to the TNM classification Any type of breast surgical procedure Any type of preoperative and/or postoperative adjuvant chemotherapy prior to enrollment Capable of receiving the study drug within 12 weeks after surgery or after postoperative chemotherapy completion prior to enrollment Eastern Cooperative Oncology Group performance status of Grade 0 or 1  Exclusion Criteria:  Bilateral oophorectomy or ovarian irradiation No use of other OFS drugs