title: A systematic review and meta-analysis of the utility of EUS for preoperative staging for gastric cancer.
abstract: BACKGROUND
  Accurate preoperative staging is important in determining the appropriate treatment of gastric cancer. Recently, endoscopic ultrasound (EUS) has been introduced as a staging modality. However, reported test characteristics for EUS in gastric cancer vary. Our purpose in this study was to identify, synthesize, and evaluate findings from all articles on the performance of EUS in the preoperative staging of gastric cancer.
  
  
  METHODS
  Electronic literature searches were conducted using Medline, Embase, and the Cochrane Central Register of Controlled Trials from 1 January 1998 to 1 December 2009. All search titles and abstracts were independently rated for relevance by a minimum of two reviewers. Meta-analysis for the performance of EUS was analyzed by calculating agreement (Kappa statistic), and pooled estimates of accuracy, sensitivity, and specificity for all EUS examinations, using histopathology as the reference standard. Subgroup analyses were also performed.
  
  
  RESULTS
  Twenty-two articles met our inclusion criteria and were included in the review. EUS pooled accuracy for T staging was 75% with a moderate Kappa (0.52). EUS was most accurate for T3 disease, followed by T4, T1, and T2. EUS pooled accuracy for N staging was 64%, sensitivity was 74%, and specificity was 80%. There was significant heterogeneity between the included studies. Subgroup analyses found that annual EUS volume was not associated with EUS T and N staging accuracy (P = 0.836, 0.99, respectively).
  
  
  CONCLUSIONS
  EUS is a moderately accurate technique that seems to describe advanced T stage (T3 and T4) better than N or less advanced T stage. Stratifying by EUS annual volume did not affect EUS performance in staging gastric cancer.
authors.affiliation: Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Canada.
authors.forename: Roberta
authors.initials: R
authors.lastname: Cardoso
authors.forename: Natalie
authors.initials: N
authors.lastname: Coburn
authors.forename: Rajini
authors.initials: R
authors.lastname: Seevaratnam
authors.forename: Rinku
authors.initials: R
authors.lastname: Sutradhar
authors.forename: Laercio Gomes
authors.initials: LG
authors.lastname: Lourenco
authors.forename: Alyson
authors.initials: A
authors.lastname: Mahar
authors.forename: Calvin
authors.initials: C
authors.lastname: Law
authors.forename: Elaine
authors.initials: E
authors.lastname: Yong
authors.forename: Jill
authors.initials: J
authors.lastname: Tinmouth
mesh_terms: D019160:Endosonography / Q000379:methods*; D006801:Humans; D009367:Neoplasm Staging; D011300:Preoperative Care / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013274:Stomach Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery