Different response to neoadjuvant chemotherapy for different molecular subtypes in patients with locally advanced breast cancer

Abstract

The aim of this study was to evaluate the impact of different molecular subtypes defined by immunohistochemistry (IHC) staining on the response rate for patients with locally advanced breast cancer received neoadjuvant chemotherapy. One hundred and seven breast cancer patients admitted from 2007 to 2011 who received 4 cycles of docetaxel/epirubicin-combined (TE) neoadjuvant chemotherapy were retrospectively reviewed, the patients were classified into 4 subtypes: luminal A, luminal B, HER-2 and triple negative breast cancer (TNBC) according to different combination patterns of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor-2 (HER-2) expression defined by IHC method. The correlation between response rate and the molecular subtypes were analyzed. The pathological complete response (PCR), clinical complete response (CCR), clinical partial response (CPR), and clinical stable disease (CSD) rate of whole group was 15.89% (17/107), 22.43% (24/107), 63.55% (68/107), 14.02% (15/107), respectively, and the overall response rate (ORR) was 85.98% (92/107). The PCR rate and ORR of luminal A, luminal B, HER-2 and TNBC subtypes was 4.76% and 73.81%; 16.67% and 83.33%; 17.65% and 100.00%; 30.00% and 96.67%, respectively. The PCR and ORR rate of HER-2/TNBC subtypes was higher than that of luminal A/B subtypes (P = 0.019, P = 0.002, respectively). Different molecular subtypes display different response rate for patients with locally advanced breast cancer received neoadjuvant TE chemotherapy, HER-2/TNBC subtypes have a higher PCR and ORR rate than that of luminal A/B subtypes.