Gastrectomy plus chemotherapy versus chemotherapy alone for advanced gastric cancer with a single non-curable factor: Exploratory analysis in the p...

Date 29 September 2019
Event ESMO 2019 Congress
Session Poster Display session 2
Topics Gastric Cancer
Presenter Takaki Yoshikawa
Citation Annals of Oncology (2019) 30 (suppl_5): v253-v324. 10.1093/annonc/mdz247
Authors T. Yoshikawa1, K. Fujitani2, H. Yang3, J. Mizusawa4, M. Terashima5, T. Tsujinaka6, K. Nakamura7, H. Katayama7, S. Jin8, S. Kong9, Y. Iwasaki10, H. Kim11, A. Takagane12, S. Lee13, J. Bae14, S.H. Noh15, M. Sasako16
  • 1Gastric Surgery, National Cancer Center Hospital, 104-0045 - Tokyo/JP
  • 2Gastrointestinal Surgery, Osaka General Medical Center, Osaka/JP
  • 3Surgery & Cancer Research Institute, Seoul National University Hospital, Seoul/KR
  • 4Japan Clinical Oncology Group Data Center, National Cancer Center Hospital, 104-0045 - Tokyo/JP
  • 5Division Of Gastric Surgery, Shizuoka Cancer Center, 411-8777 - Shizuoka/JP
  • 6Surgery, Kaizuka City Hospital, 597-0015 - Kaizuka/JP
  • 7Japan Clinical Oncology Group Operations Office, National Cancer Center Hospital, Tokyo/JP
  • 8Surgery, Korea Cancer Center Hospital, Seoul/KR
  • 9Department Of Surgery & Cancer Research Institute, Seoul National University Hospital, Seoul/KR
  • 10Surgery, Komagome Tokyo Metropolitan Hospital, Tokyo/JP
  • 11Surgery, Seoul National University Bundang Hospital, Seongnam/KR
  • 12Surgery, Hakodate Goryokaku Hospital, Hakodate/JP
  • 13Surgery, Kosin University Gospel Hospital, Pusan/KR
  • 14Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul/KR
  • 15Surgery, Gangnam Severance Hospital, Seoul/KR
  • 16Surgery, Yodogawa Christian Hospital, 533-0024 - Osaka/JP

Abstract

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.