This is a multicenter, randomized, open-Label , non-inferiority phase III study . All premenopausal women breast cancer subjects were randomly allocated to either the study group or control group in a 1:1 ratio. Furthermore, all subjects received tamoxifen citrate treatment throughout the entire duration of the study. The efficacy of maintaining serum E2 levels ≤30 pg/mL at 4-48 weeks post-treatment will be assessed in both groups.
