ERBB2 and breast cancer: Inhibitors targeting programmed death‐1 (PD‐1)/programmed death ligand‐1 (PD‐L1) have transformed the treatment landscape for various malignancies, including advanced human epidermal growth factor receptor 2 (HER2) negative breast cancer, demonstrating significant clinical efficacy and long‐term survival benefits.1, 2, 3, 4