BCs are generally divided into three subtypes based on the expression of two or three major drivers or biomarkers: (1) hormone receptor-positive (HR+) or luminal, (2) human epidermal growth factor receptor 2-positive (HER2+) or erythroblastic oncogene B 2-positive (ERBB2+), and (3) triple-negative breast cancer (TNBC) subtypes [2]. The gene discussed is ERBB2; the disease is triple-negative breast carcinoma.