OFS plus AI or SERM vs. SERM alone in premenopausal women with hormone receptor-positive breast cancer: a prospective cohort study using the real-world database

Background Ovarian function suppression (OFS) plus other endocrine treatment was recommended to hormone receptor (HR)-positive breast cancer by some guidelines recently. We performed this study to validate the survival benefits of OFS plus aromatase inhibitors (AI) or selective estrogen receptor modulators (SERM) in the real world.