Long Term Cohort Study of Adding Ovarian Function Suppression to Tamoxifen in Young Women

This study evaluates the long-term effects of adding 2 years of ovarian function suppression (OFS) to tamoxifen therapy in young premenopausal women with hormone receptor-positive breast cancer after chemotherapy. The study will assess recurrence, breast cancer-specific survival, and overall survival beyond 10 years to determine the long-term benefits of OFS treatment.

NCT Number	NCT07735897
Lead Sponsor	MedicalExcellence Collaborators: Asan Medical Center
Conditions	Breast Cancer
Enrollment	1,483 participants
Start Date	2026-07-01
Primary Completion	2034-03-01 (estimated)
Study Completion	2034-05-01 (estimated)
Updated on ClinicalTrials.gov	2026-07-31