Chemotherapeutic strategies for patients with HER2+ BC are based on intravenous therapy with paclitaxel–trastuzumab, adriamycin–cyclophosphamide–paclitaxel–trastuzumab ± pertuzumab, or docetaxel–carboplatin–trastuzumab ± pertuzumab. This evidence concerns the gene ERBB2 and breast cancer.