Abstract B05: Pathologic complete response is an independent prognostic factor for locoregional recurrence in locally advanced breast cancer patients after neoadjuvant chemotherapy

Abstract

Abstract Background: Neoadjuvant chemotherapy (NAC) has been the standard approach for downstaging in locally advanced breast cancer and can improve breast conservation rates. Pathologic complete response (pCR) after NAC has been reported to have favorable long-term outcome. However, there is still high locoregional recurrence (LRR) rate after NAC. The aim of this study is to analyze the relationship of pCR and LRR. Method: A retrospective study was analyzed from 2002 to 2011, and a total of 263 invasive breast cancer patients had NAC and, following mastectomy or breast conserving surgery (BCS) at Linkou Chang Gung Memorial Hospital, were enrolled. Concurrent weekly epirubicin and docetaxel was standard NAC regimen and adjuvant therapy including hormone therapy, radiotherapy, and target therapy was started postoperatively according to the pathologic characters. Result: The median age was 48 years old (range 18-75). The mean tumor size at diagnosis was 6.0 cm (range 2.0-22.0). The median follow-up time was 54.6 months (range 9.2-126.9). After neoadjuvant chemotherapy, 200 (76%) patients underwent mastectomy and 63 (24%) patients underwent BCS. 29 (11%) patients achieved pCR in this study. In univariate analysis, age<50, negative ER, negative PR, positive HER2, luminal B (HER2 positive) and HER2 overexpression, triple-negative subtype were factors to predict pCR. In multivariate analysis, age <50, luminal B (HER2 positive), HER2 overexpression, and triple-negative subtype were factors to predict pCR. No patients in pCR group developed LRR compared with 31 (13.2%) patients with LRR in non-pCR group. In multivariate analysis, pCR and age <50 were independent prognostic factors for LRR. Conclusion: Our findings suggested that pCR and younger age are independent prognostic factors for LRR in breast cancer patients after NAC with concurrent eprubicin and docetaxel. Citation Format: Hsu-Huan Chou, Shin-Che Chen. Pathologic complete response is an independent prognostic factor for locoregional recurrence in locally advanced breast cancer patients after neoadjuvant chemotherapy [abstract]. In: Proceedings of the AACR Special Conference: Advances in Breast Cancer Research; 2017 Oct 7-10; Hollywood, CA. Philadelphia (PA): AACR; Mol Cancer Res 2018;16(8_Suppl):Abstract nr B05.