title: Endoscopic ultrasound can improve the selection for laparoscopy in patients with localized gastric cancer.
abstract: BACKGROUND
  The majority of newly diagnosed patients with gastric cancer have disease that is not resectable because of local extension or metastatic (M1) disease. Laparoscopy is a recommended staging evaluation to identify occult peritoneal metastatic disease. We determined if endoscopic ultrasound (EUS) could improve the selection of patients for laparoscopy.
  
  
  METHODS
  Gastric cancer patients being screened for a preoperative chemotherapy clinical trial were prospectively examined. Patients underwent standard preoperative assessment. Those without obvious metastatic disease were referred for EUS and laparoscopy. EUS divided patients into risk categories for metastatic disease: low risk (T1-2, N0) and high risk (T3-4, N+, or both). Laparoscopy categories were M1 and M0. The ability of EUS to predict subradiographic peritoneal metastatic disease was evaluated.
  
  
  RESULTS
  Ninety-four patients were studied. The majority were EUS high risk (72%). Occult metastatic disease was identified in 19 patients, 18 of whom had high-risk EUS stage. The yields of identifying M1 disease by laparoscopy in EUS high- and low-risk patients were 25% (95% CI, 15% to 37%) and 4% (95% CI, 0.1% to 20%), respectively. The negative predictive value of low-risk EUS for laparoscopy and pathologic M0 was 96% (exact 95% CI, 80% to 100%).
  
  
  CONCLUSIONS
  This study suggested that laparoscopy can be avoided in patients with EUS early-stage gastric cancer. Patients with more advanced disease are at higher risk of occult peritoneal disease and require laparoscopy. Validation with greater numbers is warranted, but, based on these data, we propose a new staging algorithm allowing EUS low-risk patients to proceed directly to resection.
authors.affiliation: Gastrointestinal Oncology Service, Memorial Sloan-Kettering Cancer Center, and the Department of Medicine, Weil Cornell Medical College of Cornell University, New York, NY, USA.
authors.forename: Derek G
authors.initials: DG
authors.lastname: Power
authors.forename: Mark A
authors.initials: MA
authors.lastname: Schattner
authors.forename: Hans
authors.initials: H
authors.lastname: Gerdes
authors.forename: Baruch
authors.initials: B
authors.lastname: Brenner
authors.forename: Arnold J
authors.initials: AJ
authors.lastname: Markowitz
authors.forename: Marinela
authors.initials: M
authors.lastname: Capanu
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Coit
authors.forename: Murray
authors.initials: M
authors.lastname: Brennan
authors.forename: David P
authors.initials: DP
authors.lastname: Kelsen
authors.forename: Manish A
authors.initials: MA
authors.lastname: Shah
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D019160:Endosonography; D005260:Female; D006801:Humans; D010535:Laparoscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods*; D018579:Patient Selection; D010534:Peritoneal Neoplasms / Q000556:secondary; D011237:Predictive Value of Tests; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery*