70P - “Early tumor shrinkage” might be a novel predictive factor relating to pCR in neoadjuvant chemotherapy for resectable breast cancer

Date 18 December 2016
Event ESMO Asia 2016 Congress
Session Poster lunch
Topics Cytotoxic agents
Breast Cancer, Early Stage
Presenter Takuro Saiki
Citation Annals of Oncology (2016) 27 (suppl_9): ix19-ix29. 10.1093/annonc/mdw575
Authors T. Saiki1, A. Ishiguro1, M. Abe2, Y. Tabata2, H. Kato2, Y. Narita2
  • 1Medical Oncology, Teine Keijinkai Hospital, 006-8555 - Sapporo/JP
  • 2Breast Surgery, Teine Keijinkai Hospital, 006-8555 - Sapporo/JP

Abstract

Background

Administering 100mg/m2 of epirubicin and cyclophosphamide(EC) followed by taxanes and/or trastuzumab is the standard treatment for resectable breast cancer as neoadjuvant chemotherapy at our institution. The objective of this study is to clarify efficacy and safety of the treatment.

Methods

Between March 2010 and April 2016, fifty-four female patients with locally invasive ductal carcinoma who received neoadjuvant chemotherapy were reviewed retrospectively. This study investigated the correlation between pathological complete response (pCR) and clinicopathological factors in clinical and histological therapeutic response. We defined the pCR as ypT0 ypN0 or ypT0/is ypN0.

Results

Patient characteristics were as follows. The median age was 55.3 years (31-79). Patients(pts) were classified into 6 groups in this study (luminal A: 4, luminal B (HER2-): 16, luminal B (HER2+): 10, HER2+: 10, triple negative: 10, undeterminable hormone-positive: 4). Histological therapeutic effect of more than Grade 2 was 29 pts (53.7%). The pCR rate was 20.4% (luminal B (HER2-): 2, luminal B (HER2+): 1, HER2+: 4, triple negative: 4). Relative dose intensity (RDI) more than 85% in treatment with neoadjuvant EC was 87.0% and all patients of the pCR were included. Patients who achieved partial response in RECIST just after first 2 cycles of EC had significantly higher pCR rate (p = 0.030).

Conclusions

Patients with HER2+ and RDI more than 85% appeared to have favorable histological therapeutic effect. This study also showed that “early tumor shrinkage” might be a novel predictive factor relating to pCR.

Clinical trial indentification

Legal entity responsible for the study

N/A

Funding

N/A

Disclosure

All authors have declared no conflicts of interest.