Current perspectives on genotype classification and individualized drug targeting in triple-negative breast cancer

Abstract

Triple negative breast cancer (TNBC), a special subset of breast cancer, refers to negative expressions of estrogen receptors (ER), progesterone receptors (PR) and human epidermal growth receptor 2 (HER2). It is associated with extreme local recurrence and distant metastasis with highly invasive character. With advances in genomics, the bases of molecular classification of TNBC now include the heterogeneity of its expression at the molecular level and clinical pathology, apart from classical immunohistochemistry. Every subtype of TNBC has different individualized target drugs, which include epidermal growth factor receptor (EGFR) inhibitor, poly-AD-ribose polymerase (PARP) inhibitor, anthracycline or paclitaxel, immunotherapy and vascular endothelial growth factor receptor (VEGFR) inhibitor. Combinations of target drugs are also used. Thus, there are no widely recognized standards of genotype classification and individualized drug targeting in TNBC. In this review, relevant studies and latest developments on TNBC are presented.