Breast cancer is a complex heterogeneous tumor that can be classified according to histological features as hormone receptor (ER+, PR+/-), human epidermal growth factor receptor 2+ (HER2+), and triple-negative breast cancer (TNBC), also known as basal cell type, which are key factors affecting patient prognosis (5, 6). The gene discussed is ERBB2; the disease is breast carcinoma.