Triple-negative breast cancer subtypes and pathologic complete-response rate to neoadjuvant chemotherapy: Results from the GEICAM/2006-2003 study.

1024 Background: Triple negative breast cancer (TNBC) is a heterogeneous disease with distinct molecular subtypes that differentially respond to chemotherapy (CHT) and targeted agents. In a recent study, Lehmann et al. (JCI 2011) identified six molecular subtypes of TNBC, characterized on the basis of gene ontologies and differential gene expression. However, their clinical utility remains unclear. We aimed to explore the clinical relevance of these molecular subtypes in TNBC determining differences in response to neoadjuvant chemotherapy in a randomized phase II trial, the GEICAM/ 2006-03. Methods: The GEICAM/ 2006-03 study evaluated a regimen of anthracyclines and taxanes +/- carboplatin in the neoadjuvant treatment of patients (pts) with TNBC (Alba, BCRT 2012). We determined TNBC molecular subtypes in FFPE pre-treatment tumor biopsies from pts recruited in this study. Gene expression profile was determined using HTA 2.0 arrays (Illumina). Subtypes were identified with the online tool TNBC type (http://...