title: Neoadjuvant chemotherapy for nonmetastatic esophago-gastric adenocarcinomas: a systematic review and meta-analysis.
abstract: OBJECTIVE
  A systematic review and meta-analysis was performed to investigate the efficacy of neoadjuvant chemotherapy for nonmetastatic esophago-gastric adenocarcinomas.
  
  
  METHODS
  Electronic databases were searched systematically from January 1980 to July 2012 and a total of 2,587 patients from 17 randomized controlled trials were subjected to meta-analysis. The odds ratios (ORs) for overall survival (OS) and progression-free survival (PFS) were calculated.
  
  
  RESULTS
  Seventeen randomized controlled trials were obtained and various comparisons of treatment approaches were performed. Randomized controlled trials detected no differences in these comparisons: R0 resection for neoadjuvant chemotherapy versus none; Preoperative chemotherapy versus surgery alone: 3-year OS, 5-year OS, 5-year OS in Europe, 3-year PFS; Preoperative chemotherapy plus postoperative chemotherapy versus postoperative chemotherapy: 1-year OS, 5-year OS; Preoperative chemotherapy versus preoperative chemoradiotherapy: 3-year OS. Randomized controlled trials detected significant differences in these comparisons: Preoperative chemotherapy plus postoperative chemotherapy versus surgery alone: 3-year and 5-year PFS, 5-year OS; Subgroup analysis examining preoperative chemotherapy versus surgery alone: 5-year OS in Asia; Preoperative chemotherapy versus postoperative chemotherapy: 1-year OS.
  
  
  CONCLUSIONS
  The current limited evidence suggests that preoperative chemotherapy can be applied to patients with nonmetastatic esophago-gastric adenocarcinomas (specifically, advanced esophago-gastric cancer). However, the results should be interpreted with caution because of the statistically low power and the heterogeneity among study designs; therefore, our results need validations in future studies.
authors.affiliation: Department of Gastrointestinal Surgery, the Fourth Affiliated Hospital of China Medical University, Shenyang City, China.
authors.forename: Chun-Dong
authors.initials: CD
authors.lastname: Zhang
authors.forename: Yong-Ji
authors.initials: YJ
authors.lastname: Zeng
authors.forename: Hong-Wu
authors.initials: HW
authors.lastname: Li
authors.forename: Zhe-Ming
authors.initials: ZM
authors.lastname: Zhao
authors.forename: Jia-Kui
authors.initials: JK
authors.lastname: Zhang
authors.forename: Dong-Qiu
authors.initials: DQ
authors.lastname: Dai
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000401:mortality / Q000601:surgery; D017024:Chemotherapy, Adjuvant; D018572:Disease-Free Survival; D004938:Esophageal Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000601:surgery; D006801:Humans; D020360:Neoadjuvant Therapy; D059035:Perioperative Period; D016032:Randomized Controlled Trials as Topic; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000601:surgery; D016896:Treatment Outcome