ERBB2 and breast cancer: Fig. 3 shows the histological classification of BC.28 The identification of biomarkers of cancer is among the most effective methods for identifying malignant and even premalignant lesions in the early stages.29 The study of gene expression arrays has contributed to the understanding of many markedly distinct BC subtypes.30 BC can currently be categorized as luminal A, luminal B, HER2-overexpressing, or triple-negative on the basis of genetic testing, histopathology and immunohistochemical analysis, based on the 2011 St.