Abstract 2787
Background
Neoadjuvant studies in breast cancer (BC) patients have well-demonstrated that attaining pathological complete response (pCR) is associated with improved event-free survival (EFS) and overall survival (OS); and the association is strong in triple negative BC (TNBC) subtype. This study aimed to comprehensively evaluate the association of pCR and survival outcomes in TNBC by incorporating most recent studies; and to explore the impact of different study settings, thresholds of hormone receptor positivity defining TNBC and adjuvant chemotherapy usage on this association.
Methods
A literature search of neoadjuvant studies in TNBC was conducted up to October 2018. Clinical trials (CTs), real-world evidence (RWE) studies and meta-analyses (MA) with EFS/OS reported by pCR outcome were included. Main analyses were restricted to pCR definition of absence of tumor in the breast and axillary nodes, which is aligned with FDA guidance. Hazard ratios (HRs) evaluating the association between pCR and EFS/OS were derived from meta-analyses using fixed-effect and random-effects models. To further quantify the association, meta-analyses were conducted to synthesize the published survival curves by pCR outcome. A random-effects frailty model was utilized to account for between-study variation.
Results
Four randomized CTs, 2 single-arm CTs, 18 RWE studies and 1 MA for a total of 4,330 patients with TNBC were included in this study. Achieving pCR was strongly associated with improved survival outcomes (HR of EFS: 0.26, 95% CI: 0.22-0.30; and HR of OS: 0.20, 95% CI: 0.16-0.25). HR results were similar across study settings of CTs, RWE and MA. TNBC definition and adjuvant chemotherapy use did not have significant impact on HR results. The meta-analyses showed numerically longer survival in studies that reported adjuvant chemotherapy usage compared with those which did not, irrespective of attainment of pCR.
Conclusions
This study confirms the strong association between pCR and survival outcomes in TNBC based on evidence synthesis from both clinical and real-world settings. In addition, this study suggests potential survival benefit of subsequent adjuvant therapy for TNBC patients who received neoadjuvant therapy.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Merck & Co., Inc.
Funding
Merck & Co., Inc.
Disclosure
P.A. Fasching: Advisory / Consultancy: Merck & Co., Inc. M. Huang: Full / Part-time employment: Merck & Co., Inc. J. Cortés: Advisory / Consultancy: Merck & Co., Inc. J. Zhao: Full / Part-time employment: Merck & Co., Inc. J. O’Shaughnessy: Advisory / Consultancy: Merck & Co., Inc. P. Hu: Full / Part-time employment: Merck & Co., Inc. A. Haiderali: Full / Part-time employment: Merck & CO., Inc. V. Karantza: Full / Part-time employment: Merck & Co., Inc. G. Aktan: Full / Part-time employment: Merck & Co., Inc. A. Briggs: Advisory / Consultancy: Merck & Co., Inc. S. Ramsey: Advisory / Consultancy: Merck & Co., Inc. C.Z. Qi: Advisory / Consultancy, Employee of Analysis Group, Inc., which has received consulting fees from Merck & Co., Inc.: Merck & Co., Inc. J. Xie: Advisory / Consultancy, Employee of Analysis Group, Inc., which has received consulting fees from Merck & Co., Inc.: Merck & Co., Inc. C. Gu: Advisory / Consultancy, Employee of Analysis Group, Inc., which has received consulting fees from Merck & Co., Inc.: Merck & Co., Inc. K. Qian: Advisory / Consultancy, Employee of Analysis Group, Inc., which has received consulting fees from Merck & Co., Inc.: Merck & Co., Inc. M. Yuan: Advisory / Consultancy, Employee of Analysis Group, Inc., which has received consulting fees from Merck & Co., Inc.: Merck & Co., Inc. E.Q. Wu: Advisory / Consultancy, Employee of Analysis Group, Inc., which has received consulting fees from Merck & Co., Inc.: Merck & Co., Inc.
Resources from the same session
4581 - Timing to achieve complete response (CR) after definitive chemoradiotherapy (ChRT) in patients with squamous cell carcinoma of the anal (SCCAC) with and without HIV infection: a multicenter retrospective study
Presenter: Marcos Camandaroba
Session: Poster Display session 2
Resources:
Abstract
1712 - Planned organ preservation for T2 T3 M0 rectal adenocarcinoma. A possible option using chemoradiotherapy (CRT) and Contact X-ray Brachytherapy (CXB). A French multicenter study.
Presenter: Jean-Pierre Gérard
Session: Poster Display session 2
Resources:
Abstract
4639 - A Phase 1b Study of E7046 (AN0025) in Combination With Radiotherapy/Chemoradiotherapy (RT/CRT) in Preoperative Treatment of Rectal Cancer
Presenter: Lucjan Wyrwicz
Session: Poster Display session 2
Resources:
Abstract
2310 - Upfront radical surgery with total mesorectal excision (TME) versus preoperative chemoradiotherapy followed by TME in clinical stage II/III patients with rectal cancer: a propensity score analysis
Presenter: Ahrong Ham
Session: Poster Display session 2
Resources:
Abstract
2747 - Neoadjuvant chemoradiotherapy with/without lateral lymph node dissection for low rectal cancer: Which patients can benefit?
Presenter: Daisuke Nishizaki
Session: Poster Display session 2
Resources:
Abstract
2877 - The impact of completeness of chemotherapy on the efficacy of irinotecan in the preoperative chemoradiotherapy of locally advanced rectal cancer.
Presenter: Jingwen Wang
Session: Poster Display session 2
Resources:
Abstract
3050 - Feasibility of robot-assisted surgery in elderly patients with rectal cancer
Presenter: Wei-Chih Su
Session: Poster Display session 2
Resources:
Abstract
4109 - Feasibility of chemoradiotherapy in rectal cancer patients with peritumoral abscesses and fistulas: a case-control non-inferiority trial
Presenter: Valerii Ivanov
Session: Poster Display session 2
Resources:
Abstract
4813 - Differential of the nutritional index before and after neoadjuvant chemoradiotherapy as a prognostic factor of recurrence in patients with locally advanced adenocarcinoma of the rectum
Presenter: Leslie Navia-Ortuño
Session: Poster Display session 2
Resources:
Abstract
5345 - Short-term Clinical Outcomes of Robotic-Assisted Total Mesorectal Excision in Rectal Cancer after concurrent chemoradiotherapy
Presenter: Pojung Chen
Session: Poster Display session 2
Resources:
Abstract