title: Adjuvant chemotherapy in gastric cancer: a meta-analysis of randomized trials and a comparison with previous meta-analyses.
abstract: OBJECTIVE
  Up to now adjuvant chemotherapy after curative resection for gastric cancer (GC) has been considered an experimental approach. The results of existing phase III randomized trials comparing chemotherapy with control after surgery are controversial. Three meta-analyses have been published in recent years. It is likely that each of them presents a theoretical bias, mainly as regards the inclusion criteria of the trials. In this article we re-examine this potential bias, highlighting the differences between the present and past meta-analyses on adjuvant chemotherapy for GC.
  
  
  METHODS
  Only randomized controlled clinical trials comparing systemic adjuvant chemotherapy with control after radical resection of GC were eligible. Total mortality was assessed as outcome measure of the treatment effect and a pooled odds ratio was calculated using the Peto-Mantel-Haenszel method.
  
  
  RESULTS
  After the selection process 17 papers (18 comparisons) proved eligible for inclusion in the meta-analysis with a total of 3118 patients, of whom 1546 randomized to the treatment arms and 1572 to the control arms; 762 and 871 deaths occurred in the treatment and control arms, respectively. Statistical analysis suggests an absence of significant heterogeneity between the trials and a significant advantage in survival for adjuvant chemotherapy (pooled odds ratio, 0.72, 95% Cl, 0.62-0.84).
  
  
  CONCLUSIONS
  Our meta-analysis would seem to indicate that adjuvant chemotherapy results in a significant survival advantage in patients with GC. However, this observation undoubtedly requires confirmation in large randomized controlled trials including cisplatin before adjuvant chemotherapy after curative resection for GC can be proposed for use in clinical practice.
authors: Division of Medical Oncology, Ospedale Infermi, Rimini, Italy. ilariapanzini@virgilio.it
authors: Ilaria
authors: I
authors: Panzini
authors: Lorenzo
authors: L
authors: Gianni
authors: Pier Paolo
authors: PP
authors: Fattori
authors: Davide
authors: D
authors: Tassinari
authors: Manuela
authors: M
authors: Imola
authors: Paolo
authors: P
authors: Fabbri
authors: Valentina
authors: V
authors: Arcangeli
authors: Giuliana
authors: G
authors: Drudi
authors: Debora
authors: D
authors: Canuti
authors: Francesca
authors: F
authors: Fochessati
authors: Alberto
authors: A
authors: Ravaioli
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D017024:Chemotherapy, Adjuvant; D006801:Humans; D007167:Immunotherapy; D016017:Odds Ratio; D011379:Prognosis; D016032:Randomized Controlled Trials as Topic; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000601:surgery; D015996:Survival Rate; D016896:Treatment Outcome