Triple negative breast cancer subtypes and pathologic complete response rate to neoadjuvant chemotherapy

Triple negative breast cancer is a heterogeneous disease with distinct molecular subtypes that differentially respond to chemotherapy and targeted agents. The purpose of this study was to explore the clinical relevance of Lehmann triple negative breast cancer subtypes by identifying any differences in response to neoadjuvant chemotherapy among them. We performed a retrospective analysis in paraffined pre-treatment tumor biopsies from 119 triple negative breast cancer patients (88 patients treated with neoadjuvant anthracyclines and/or taxanes and 31 with anthracyclines and/or taxanes plus carboplatin). We determined Lehmann subtypes by gene-expression profiling with the GeneChip® Human Transcriptome Array 2.0. (Affymetrix). Data were normalized with the Robust Multichip Analysis (RMA) algorithm in the Affymetrix Expression Console (EC, v.1.4.1) and annotated in the statistical computing environment R (v.3.2.3) using hg19 human genome built. Duplicated genes were mean summarized.