Triple-negative breastcancer (TNBC) is a highly aggressive breastcancer type with a poor prognosis and accounts for approximately 15%of total breast cancer cases.1 TNBC cellslack the expression of the estrogen receptor (ER), progesterone receptor(PR), and human epidermal growth factor receptor-2 (HER2). The gene discussed is ERBB2; the disease is breast carcinoma.