In summary, among women with ER+/HER2- BC with 1–3 positive axillary lymph nodes, and a RS of 20-25—in contrast to the RxPONDER—we observed that CET was associated with an OS benefit in women regardless of age underscoring that there could be hormone independent anti-tumor effects of chemotherapy in ER+ breast cancer. This evidence concerns the gene ERBB2 and breast cancer.