NRG-BR009: Testing the addition of chemotherapy to the usual treatment of ovarian function suppression plus hormonal therapy in premenopausal ER-positive/HER2-negative breast cancer patients who are at high risk of cancer returning.
This Phase III Trial will determine whether adjuvant chemotherapy (ACT) added to ovarian function suppression (OFS) plus endocrine therapy (ET) is superior to OFS plus ET in improving invasive breast cancer-free survival (IBCFS) among premenopausal, early- stage breast cancer (EBC) patients with estrogen receptor (ER)-positive, HER2-negative tumors and 21-gene recurrence score (RS) between 16-25 (for pN0 patients) and 0-25 (for pN1 patients).