Breast cancers can be categorized according to their surface receptors as endocrine receptor (ER; estrogen or progesterone receptor) positive (BRER), human epidermal growth factor receptor 2 (HER2) positive, triple‐positive (BRTP: estrogen, progesterone, and HER2 receptor negative), and triple‐negative (BRTN) [68]. This evidence concerns the gene ERBB2 and breast cancer.