ERBB2 and neoplasm: Detected mutations were more frequent in luminal B tumors (61.1%; 11/18), followed by the luminal B/HER2-positive subtype (50%; 4/8) and triple-negative tumor samples (42.9%; 3/7), with no mutations identified in HER2-positive (n = 4) and luminal A (n = 3) tumor subtypes.