The intrinsic, molecular subtypes of invasive breast carcinomas are clinically relevant classifications, which include triple-negative breast cancer (TNBC), human epidermal growth factor receptor 2 (HER2)-enriched (nonluminal), luminal B-like HER2-positive, luminal B-like HER2-negative, and luminal A breast cancer [2,4]. The gene discussed is ERBB2; the disease is breast carcinoma.