Abstract 3187
Background
REGATTA is a phase III trial to compare chemotherapy alone (arm A) and reduction surgery followed by chemotherapy (arm B) for advanced gastric cancer with a single non-curable factor. The trial failed to show superiority of reduction surgery, which could be partially explained by poor compliance of chemotherapy in arm B. This exploratory analysis aims to clarify whether upfront surgery has survival benefit in patients (pts) who could continue chemotherapy for some period, enrolled in REGATTA.
Methods
In REGATTA, 175 pts were assigned to arm A (86 pts) and arm B (89 pts). S-1 80 mg/m2 for 3 weeks and CDDP 60 mg/m2 on day 8 was repeated every 6 weeks. The pts were limited to those for whom chemotherapy was continued at 2, 4, or 6 months after randomization (cohort-2M, cohort-4M, or cohort-6M, respectively) and pts who underwent gastrectomy in arm A were excluded. The overall survival (OS) was defined as the duration from the date at 2, 4, or 6 months after randomization to the date of the death from any cause or to the last date of contact for a surviving pt.
Results
Examined pts were 130 (59 in arm A and 71 in arm B) in cohort-2M, 111 (50 in arm A and 61 in arm B) in cohort-4M, and 90 (43 in arm A and 47 in arm B) in cohort-6M, respectively. In cohort-2M, the median survival time (MST) was 14.1 months (m) (95% CI, 11.7-16.6) in arm A and 12.6 m (9.9-15.9) in arm B with hazard ratio (HR) of 0.935 (0.641-1.635). The OS was 9.7% (3.2-20.5) in arm A and 17.9% (9.2-28.8) in arm B at 3-year. In cohort-4M, the MST was 13.1 m (10.3-18.8) in arm A and 11.5 m (8.4-15.1) in arm B with HR of 0.954 (0.629-1.448). The OS was 11.5% (3.8-24.0) in arm A and 21.2% (11.0-33.6) in arm B at 3-year. In cohort-6M, the MST was 13.8 m (9.8-22.1) in arm A and 10.9 m (6.6-16.6) in arm B with HR of 0.860 (0.535-1.383). The OS was 13.2% (4.3-27.0) in arm A and 26.0% (13.1-41.0) in arm B at 3-year.
Conclusions
Among pts having certain period of chemotherapy, there seem to be more long survivors in arm B than the arm A. Reduction surgery may still be promising if chemotherapy compliance after surgery could be improved.
Clinical trial identification
UMIN000001012, Feb 2008.
Editorial acknowledgement
Legal entity responsible for the study
Japan Clinical Oncology Group (JCOG).
Funding
The Ministry of Health, Labour and Welfare of Japan and the Korean Gastric Cancer Association.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
4331 - STING Agonist, ADU-S100, Yields Potent Antitumor Activity and Therapeutically Favorable Immune Profile in an Esophageal Adenocarcinoma Model
Presenter: Ali Zaidi
Session: Poster Display session 2
Resources:
Abstract
1770 - Increased assessment of HER2 in metastatic gastroesophageal cancer patients: a nationwide population-based cohort study
Presenter: Willemieke Dijksterhuis
Session: Poster Display session 2
Resources:
Abstract
3755 - A new docetaxel (DOC)-based triplet regimen does not improve the outcome of metastatic (M) or locally advanced (LA) gastric cancer (GC) as compared with an epirubicin (EPI) standard triplet regimen: a GISCAD trial.
Presenter: Roberto Labianca
Session: Poster Display session 2
Resources:
Abstract
2439 - The analysis of T cell subsets and clinical efficacy of immune checkpoint blockades in patients with advanced gastric cancer using multiplex immunohistochemistry
Presenter: Tae-yong Kim
Session: Poster Display session 2
Resources:
Abstract
2211 - First-line pembrolizumab (P), trastuzumab (T), capecitabine (C) and oxaliplatin (O) in HER2-positive metastatic esophagogastric adenocarcinoma.
Presenter: Yelena Janjigian
Session: Poster Display session 2
Resources:
Abstract
3046 - Monitoring patient-specific mutation in ctDNA and CTC for tumor response evaluation after neoadjuvant chemotherapy in locally advanced gastric cancer (NCT03425058)
Presenter: Tao Fu
Session: Poster Display session 2
Resources:
Abstract
4628 - Gastric cancer screening in BRCA 2 gene mutation carriers: should it be recommended?
Presenter: Inês Oliveira
Session: Poster Display session 2
Resources:
Abstract
2127 - Interim analysis of an observational/translational study for nivolumab treatment in advanced gastric cancer: JACCRO GC-08 (DELIVER trial)
Presenter: Yu Sunakawa
Session: Poster Display session 2
Resources:
Abstract
2264 - Prediction of S-1 adjuvant chemotherapy efficacy in Stage II/III gastric cancer treatment based on comprehensive gene expression analysis
Presenter: Masanori Terashima
Session: Poster Display session 2
Resources:
Abstract
2444 - Assessing the clinical utility of circulating tumour DNA through longitudinal liquid biopsy sampling in Oesophageal adenocarcinoma
Presenter: Emma Ococks
Session: Poster Display session 2
Resources:
Abstract