49P - The role of circulating cell-free DNA measured by a simple fluorescent assay to predict relapse in triple negative breast cancer receiving neoadjuv...

Date 17 December 2016
Event ESMO Asia 2016 Congress
Session Poster lunch
Topics Anti-Cancer Agents & Biologic Therapy
Translational Research
Presenter Kwonoh Park
Citation Annals of Oncology (2016) 27 (suppl_9): ix9-ix18. 10.1093/annonc/mdw574
Authors K. Park1, M. Woo2, J.E. Kim3, J. Ahn4, K.H. Jung4, S.B. Kim5
  • 1Medical Oncology And Hematology, Pusan National University Yangsan Hospital, 50612 - Yangsan/KR
  • 2Oncology, Asan Medical Center, University of Ulsan College of Medicine, 05505 - Seoul/KR
  • 3Oncololy, Asan Medical Center, 138-736 - Seoul/KR
  • 4Department Of Oncology, Asan Medical Center, University of Ulsan College of Medicine, 138-736 - Seoul/KR
  • 5Oncology, Asan Medical Center, University of Ulsan College of Medicine, 138-736 - Seoul/KR

Abstract

Background

Prior technique to measure cell free DNA(CFD) is labor-intensive and expensive, while, recently developed fluorescent CFD assay is more simple and convenient. The aim of this study was to evaluate the role of CFD measured by a fluorescent assay as a biomarker of patients with triple negative breast cancer (TNBC) received neoadjuvant chemotherapy

Methods

This study is a biomarker substudy of prospective observational study (NCT02001519, NCT02001506). We prospectively enrolled patients with TNBC, clinical stage II or III (T > 1.5cm or lymph node > 1.5cm), who were scheduled for neoadjuvant chemotherapy. Patients received 4 cycles of adriamycin 60 mg/m2 plus cyclophosphamide 600 mg/m2 (AC) followed by 4 cycles of cisplatin or docetaxel, and surgery. Plasma samples were obtained from patients before initial chemotherapy (baseline-CFD) and after 4 cycles of AC neoadjuvant chemotherapy (AC-CFD).

Results

This study included 72 patients who met the inclusion criteria. The mean levels of baseline-CFD and AC-CFD were 239±68 ng/mL and 210±66 ng/mL, respectively, and the CFD level was significantly decreased after AC chemotherapy. (p = 0.001) The baseline-CFD was not associated with initial tumor characteristics. (T stage 1-2 vs. 3, p = 0.313; N stage 0 vs. 1-3, p = 0.317) There was no statistically significant difference between patients with response (CR or PR) to AC chemotherapy and those without response in terms of baseline-CFD, AC-CFD, and change of CFD between two values. (p = 0.814, p = 0.839, p = 0.927) With 33.6 months of median follow up, there were 18 cases of relapse. Relapsed group showed numerically higher level of baseline-CFD, although it was not statistically significant. (relapse, 259 ng/mL; non-relapse, 233 ng/mL; p = 0.161) We performed a ROC curve analysis of baseline-CFD for relapse, and found an area under the curve of 0.62 (95% CI, 0.46-0.78) at 222 ng/mL. Patients with baseline-CFD above 222 showed higher relapses than those below 222. (HR, 2.75; 95% CI, 0.96-7.84; p = 0.059)

Conclusions

The baseline-CFD obtained using a simple and convenient fluorescent assay could predict relapse, suggesting baseline-CFD as a potential biomarker for risk stratification of TNBC.

Clinical trial indentification

A biomarker substudy of prospective observational study (NCT02001519, NCT02001506)

Legal entity responsible for the study

The study was approved by the institutional review board of Asan Medical Center and conducted in accordance with the Declaration of Helsinki and Good Clinical Practice guidelines

Funding

N/A

Disclosure

All authors have declared no conflicts of interest.