Morphologic and molecular characterization of triple-negative breast carcinoma for identification of clinically relevant subtypes

Morphologic and molecular characterization of triple negative breast carcinoma for identification of clinically relevant subtypes Introduction: Breast carcinoma is the most common malignancy in women worldwide, and the number one cause of cancer death in women. Despite the recent advances in breast cancer diagnosis and treatment, a problem is still posed by the so called 'triple negative breast carcinomas' (TNBCs). These tumours are associated with poor prognosis and are unlikely to respond to hormonal or anti-HER2 therapy. TNBCs are grouped together despite the clear heterogeneity within the subtype; there is no widely accepted evidence- based and clinically relevant way to sub-classify them. Neither is there any standard form of targeted therapy for the disease. Epidermal growth factor receptor (EGFR) is being investigated as a potential target for treatment of TNBC. The purpose of this study was to try to identify clinically significant morphologic and/or immunophenotypic subtypes within the triple negative group of breast carcinomas. We also aimed to study the associations between EGFR changes and TNBC phenotype and clinical behaviour. Materials and methods: We performed an immunohistochemical (IHC), in situ hybridization and histo- morphological study on a set of 52 archive cases of pre-treatment TNBC...