title: Postoperative chemo-radiotherapy versus chemotherapy for resected gastric cancer: a systematic review and meta-analysis.
abstract: BACKGROUND
  This study conducted a systematic review and meta-analysis (direct and indirect) of published randomised controlled trials (RCTs) to compare the effects of postoperative chemo-radiotherapy (ChRT) with chemotherapy (Ch) on overall and disease-free survival (DFS) for patients with resectable gastric cancer.
  
  
  METHODS
  We searched MEDLINE and CENTRAL from the date of inception and annual meeting proceedings of American Society of Clinical Oncology and American Society for Radiation Oncology from 1999 to November 2012 for RCTs comparing postoperative ChRT with Ch, postoperative ChRT with surgery alone and postoperative Ch with surgery alone. The primary outcome was overall survival (OS); secondary outcomes included DFS and toxicity. Hazard ratios (HRs), confidence intervals (CIs) and P values (P) were estimated with fixed effects models using Revman 5.1.
  
  
  RESULTS
  We found six trials comparing postoperative ChRT with Ch (n = 1171). Meta-analysis of direct comparison trials showed that postoperative ChRT significantly improved both OS (HR 0.80, 95% CI 0.65-0.98, P = 0.03) and DFS (HR 0.76, 95% CI 0.63-0.91, P = 0.003) when compared with Ch. There were no significant differences in toxicity between the two groups.
  
  
  CONCLUSIONS
  This study suggests a survival benefit of postoperative ChRT over Ch in patients with resected gastric cancer.
authors.affiliation: Department of Radiation Oncology, National University Cancer Institute, Singapore, National University Health System, National University of Singapore, Singapore.
authors.forename: Yu Yang
authors.initials: YY
authors.lastname: Soon
authors.forename: Cheng Nang
authors.initials: CN
authors.lastname: Leong
authors.forename: Jeremy Chee Seong
authors.initials: JC
authors.lastname: Tey
authors.forename: Ivan Weng Keong
authors.initials: IW
authors.lastname: Tham
authors.forename: Jiade Jay
authors.initials: JJ
authors.lastname: Lu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059248:Chemoradiotherapy / Q000401:mortality* / Q000706:statistics & numerical data*; D017024:Chemotherapy, Adjuvant / Q000401:mortality* / Q000706:statistics & numerical data*; D019317:Evidence-Based Medicine; D006801:Humans; D038622:Internationality; D008875:Middle Aged; D015995:Prevalence; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000401:mortality* / Q000628:therapy*; D015996:Survival Rate; D016896:Treatment Outcome
keywords: chemo-radiotherapy; drug therapy; gastrectomy; radiotherapy; stomach neoplasm