Endocrine Therapies With Ovarian Function Suppression in Premenopausal Node+ Early Breast Cancer With Low Genomic Risk (INTERSTELLAR Trial, KBCSG-25)

What this Trial Is About

This research evaluates premenopausal women with estrogen receptor-positive (ER+) and HER2-negative breast cancer who have cancer spread to nearby lymph nodes (N1). The study focuses on patients who have undergone primary breast surgery and are identified as having a low genomic risk based on the OncoFREE4 multigene assay. The goal is to study the effects of ovarian function suppression combined with endocrine therapies in this specific group. Participants will receive ovarian function suppression (OFS) with endocrine treatments, which includes either tamoxifen or aromatase inhibitors, administered over a period of 5 years. The OFS may be delivered using drugs such as goserelin acetate or leuprorelin acetate. Alternatively, patients may choose to undergo bilateral salpingo-oophorectomy instead of OFS. Chemotherapy is not given to these patients. During the study, participants will be monitored for outcomes including distant recurrence-free survival over 5 years, as well as recurrence-free survival and invasive disease-free survival. Researchers will assess these outcomes to understand the long-term effects of the treatments. The total participation time aligns with the 5-year treatment period, with ongoing safety and disease status assessments throughout.

OFS in Premenopausal Node+ Breast Cancer With Low Genomic Risk