Analyzing data from 16,745 patients with BC, we demonstrated that CET was associated with 32% lower risk of death and higher 3‐ and 5‐year OS rates (98.1% vs. 97.0%, and 95.4% vs. 92.0%, respectively), when compared to ET alone in women >50 years of age with RS ≥26 pT1‐ pT2 N0M0 HR+/HER2‐BC. Here, ERBB2 is linked to breast cancer.