title: The cut-off value of tumor size and appropriate timing of follow-up for management of minimal EUS-suspected gastric gastrointestinal stromal tumors.
abstract: BACKGROUND
  The detectable rate of minimal gastric GISTs has continuously increased. While the surveillance and management of GIST <2 cm have been deemed controversial or lack evidence-based approaches.  The aim of the current study is to propose a cut-off value of tumor size for treatment policy and the appropriate timing for endoscopic ultrasonography (EUS) follow-up in the minimal EUS-suspected gastric GIST patients.
  
  
  METHODS
  A single-institution retrospective study was performed. 69 patients with EUS-suspected gastric GISTs were studied from November 2008 to March 2015. 69 patients with minimal gastric GISTs ≤2 cm diagnosed by EUS were followed for a mean period of 29 months (range, 12 to 70). An at least 20% increase of the maximal diameter of the tumors was set as a significant change.
  
  
  RESULTS
  During follow-up, Of the 69 minimal EUS-suspected GISTs, 16 (23.2%) showed significant changes in size. 11 out of 69 GISTs (15.9%), 6 out of 43 GISTs (14.0%), 7 out of 30 GISTs (23.3%) showed significant changes in size, at 1 year, 2 years, and more than 3 years respectively. The receiver operating characteristic curve analysis showed that the tumor size cut-off was 9.5 mm. Only 4.7 and 3.7% of gastric EUS-suspected GISTs of <9.5 mm in size showed significant changes at 1 year and 2 years, while 9.5% at more than 3 years. 34.6, 31.3 and 55.6% of gastric EUS-suspected GISTs of ≥ 9.5 mm in size showed significant changes at 1 year, 2 years and more than 3 years.
  
  
  CONCLUSIONS
  Minimal EUS-suspected GISTs, larger than 9.5 mm may be associated with significant progression. The patients with a ≥ 9.5 mm GIST should have a EUS 6-12months, while <9.5 mm GIST may have a EUS extended to every 2-3 years.
authors.affiliation: Department of Gastrointestinal Surgery, Peking University People's Hospital, Beijing, 100044, People's Republic of China.
authors.forename: Zhidong
authors.initials: Z
authors.lastname: Gao
authors.affiliation: Department of Gastrointestinal Surgery, Peking University People's Hospital, Beijing, 100044, People's Republic of China.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Gastroenterology and Endoscopy, Peking University People's Hospital, Beijing, 100044, People's Republic of China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Xue
authors.affiliation: Department of Gastroenterology and Endoscopy, Peking University People's Hospital, Beijing, 100044, People's Republic of China.
authors.forename: Jingtong
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Gastrointestinal Surgery, Peking University People's Hospital, Beijing, 100044, People's Republic of China.
authors.forename: Zhanlong
authors.initials: Z
authors.lastname: Shen
authors.affiliation: Department of Gastrointestinal Surgery, Peking University People's Hospital, Beijing, 100044, People's Republic of China.
authors.forename: Kewei
authors.initials: K
authors.lastname: Jiang
authors.affiliation: Department of Gastrointestinal Surgery, Peking University People's Hospital, Beijing, 100044, People's Republic of China.
authors.forename: Kai
authors.initials: K
authors.lastname: Shen
authors.affiliation: Department of Gastrointestinal Surgery, Peking University People's Hospital, Beijing, 100044, People's Republic of China.
authors.forename: Bin
authors.initials: B
authors.lastname: Liang
authors.affiliation: Department of Gastrointestinal Surgery, Peking University People's Hospital, Beijing, 100044, People's Republic of China.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Gastrointestinal Surgery, Peking University People's Hospital, Beijing, 100044, People's Republic of China.
authors.forename: Qiwei
authors.initials: Q
authors.lastname: Xie
authors.affiliation: Department of Gastrointestinal Surgery, Peking University People's Hospital, Beijing, 100044, People's Republic of China.
authors.forename: Shan
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Gastrointestinal Surgery, Peking University People's Hospital, Beijing, 100044, People's Republic of China. yeyingjiang@pkuph.edu.cn.
authors.forename: Yingjiang
authors.initials: Y
authors.lastname: Ye
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019468:Disease Management; D018450:Disease Progression; D019160:Endosonography / Q000379:methods / Q000592:standards*; D005260:Female; D005500:Follow-Up Studies; D046152:Gastrointestinal Stromal Tumors / Q000000981:diagnostic imaging / Q000473:pathology*; D005773:Gastroscopy; D006801:Humans; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D012015:Reference Standards; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D013997:Time Factors; D047368:Tumor Burden
keywords: Endoscopic ultrasound (EUS); Gastrointestinal stromal tumor (GIST); Stomach