title: Clinical course of gastrointestinal stromal tumor diagnosed by endoscopic ultrasound-guided fine-needle aspiration.
abstract: OBJECTIVE
  Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumor of the gastrointestinal tract. However, little is known about the clinical presentation of GIST, especially small lesions. The purpose of the present study was to clarify the efficacy of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for the diagnosis of GIST and to determine its clinical course.
  
  
  METHODS
  Pathological and clinical records of GIST extracted from our institutional database between 1996 and 2012 were reviewed. All GIST cases were diagnosed pathologically by surgical specimen or EUS-FNA. To examine the efficacy of EUS-FNA for the diagnosis of GIST, the pathological findings of EUS-FNA were compared with the surgical findings from resected cases. Next, to clarify the clinical presentation of GIST, imaging findings and changes in tumor size over time were evaluated in follow up.
  
  
  RESULTS
  Of 84 cases of GIST, 67 were resected surgically after EUS-FNA; tumor size was <20 mm in 19 patients, and ≥20 mm in 48 patients. For the diagnosis of small GIST<20 mm, sensitivity and positive predictive value of EUS-FNA were 81.3% and 100%, respectively. A total of 27 patients with GIST was follow up for more than 1 year. Tumor size increased significantly during follow up. However, generalized linear analysis showed that there was no significant relationship between tumor size and follow up period.
  
  
  CONCLUSIONS
  The present results showed that even small GIST can be correctly identified by EUS-FNA. Moreover, size of small GIST increased significantly during follow up.
authors: Division of Gastroenterology and Neurology, Akita University School of Medicine, Akita.
authors: Masanari
authors: M
authors: Sekine
authors: Hiroshi
authors: H
authors: Imaoka
authors: Nobumasa
authors: N
authors: Mizuno
authors: Kazuo
authors: K
authors: Hara
authors: Susumu
authors: S
authors: Hijioka
authors: Yasumasa
authors: Y
authors: Niwa
authors: Masahiro
authors: M
authors: Tajika
authors: Tsutomu
authors: T
authors: Tanaka
authors: Makoto
authors: M
authors: Ishihara
authors: Seiji
authors: S
authors: Ito
authors: Kazunari
authors: K
authors: Misawa
authors: Yuichi
authors: Y
authors: Ito
authors: Yasuhiro
authors: Y
authors: Shimizu
authors: Yasushi
authors: Y
authors: Yatabe
authors: Hirohide
authors: H
authors: Ohnishi
authors: Kenji
authors: K
authors: Yamao
mesh_terms: D000328:Adult; D000368:Aged; D061765:Endoscopic Ultrasound-Guided Fine Needle Aspiration / Q000379:methods*; D019160:Endosonography / Q000379:methods*; D005260:Female; D005743:Gastrectomy; D005770:Gastrointestinal Neoplasms / Q000175:diagnosis* / Q000601:surgery; D046152:Gastrointestinal Stromal Tumors / Q000175:diagnosis* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods*; D015203:Reproducibility of Results; D012189:Retrospective Studies
keywords: Ki-67 labelling index; clinical course; endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA); gastrointestinal stromal tumor (GIST); submucosal lesion (SML)