title: EUS clarifies the natural history and ideal management of GISTs.
abstract: OBJECTIVE
  Gastrointestinal stromal tumors (GISTs) are mesenchymal gastrointestinal tumors expressing C-kit (CD117). Endoscopic ultrasonography (EUS) evaluations of GISTs can help determine optimal therapy and follow-up care. The current study assesses the natural history of 100 GISTs evaluated by EUS, and the impact of EUS on their management.
  
  
  METHODS
  Retrospective review of 2600 EUS files performed over 11 years identified 100 patients with GISTs. Relevant data from all appropriate files and interviews with patients or family of deceased patients were tabulated regarding the GISTs.
  
  
  RESULTS
  Every GIST had definitive cytology (n=43) or histology. Seventy of the 100 patients underwent more than one evaluation. Size of the GISTs at initial diagnosis averaged 20.5 mm and at follow-up examination 23.2 mm. Fourteen of 70 GISTs showed significant enlargement (> 1 mm/month). Enlargement during follow-up of GISTs was significantly more common with GISTs over 17 mm at initial diagnosis (p<0.018). Thirty-four were excised (7 endoscopically). Clinically asymptomatic GISTs tended to be smaller. Thirteen percent of GIST patients had second primary malignancy.
  
  
  CONCLUSIONS
  EUS elucidates GIST natural history and can help guide management. GISTs larger than 17 mm should be monitored by EUS and considered for more aggressive treatment. Searching for synchronous tumors in patients with GISTs should be considered.
authors.affiliation: Department of Gastroenterology, Western Galilee Hospital, Nahariya, Israel. ramila@017.net.il
authors.forename: Jesse
authors.initials: J
authors.lastname: Lachter
authors.forename: Naseem
authors.initials: N
authors.lastname: Bishara
authors.forename: Erik
authors.initials: E
authors.lastname: Rahimi
authors.forename: Moshe
authors.initials: M
authors.lastname: Shiller
authors.forename: Hector
authors.initials: H
authors.lastname: Cohen
authors.forename: Ron
authors.initials: R
authors.lastname: Reshef
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle; D019160:Endosonography / Q000379:methods*; D046152:Gastrointestinal Stromal Tumors / Q000000981:diagnostic imaging* / Q000601:surgery; D006801:Humans; D008875:Middle Aged; D012189:Retrospective Studies