Identifying High-Risk Triple-Negative Breast Cancer Patients by Molecular Subtyping

Triple-negative breast cancer (TNBC) is considered the most aggressive type of breast cancer with limited options for therapy. TNBC is a heterogeneous disease and tumours has been classified into TNBC subtypes using gene expression profiling to distinguish basal-like1 (BL1), basal-like2 (BL2), immunomodulatory (IM), mesenchymal (M), mesenchymal/stem-like (MSL), luminal androgen receptor (LAR) and one non-classifiable group (called unstable, UNS). The aim of this study was to verify the clinical relevance of molecular subtyping of TNBCs by expression analysis to improve the individual indication of systemic therapy. Molecular subtyping was performed in 124 TNBC tumours that were obtained from a prospective, multicentre cohort including 1,270 histopathologically confirmed invasive, non-metastatic breast cancers (NCT 01592825).