title: Clinical significance of surgery for gastric submucosal tumours with size enlargement during watchful waiting period.
abstract: BACKGROUND
  The true impact of surgery for small, asymptomatic and biopsy-negative gastric submucosal tumours (SMTs) with size enlargement during 'watchful waiting' period has not been fully understood.
  
  
  METHODS
  From 2005 to 2012, 100 patients with gastric SMTs underwent surgery. Twenty-three of them with size enlargement during observation period were enrolled in the retrospective analysis. Data included clinicopathologic findings, genetic findings, operative outcomes and prognoses.
  
  
  RESULTS
  All patients (13 males, 10 females), with median age of 54 (41-71), had their lesions detected by routine health check-up (n=21) or incidentally (2). The tumours were 1.8 (0.5-4.0)cm in size at their initial detection, and enlarged up to 3.2 (2.0-7.0)cm at the operation during 63.0 (14.6-233.7) months. As surgical procedure, laparoscopic partial gastrectomy accounted for the majority (78.3%). Histologic examination revealed gastrointestinal stromal tumour (GIST) (21) and schwannoma (2). Although 16 out of 21 GISTs were categorised into 'Very low' (1), and 'Low' (13) risk according to Fletcher's classification, 'Intermediate' (5) and 'High' (2) risk were identified in the series. No recurrences/metastases were noted in 23.2 (0.9-87) months of postoperative follow-up.
  
  
  CONCLUSIONS
  Our study revealed the existence of high mitotic GISTs in asymptomatic, small gastric SMTs with size enlargement, and laparoscopic surgery was safely applied to majority of those cases. Prompt surgical intervention should therefore be considered for those lesions.
authors.affiliation: Division of Gastroenterological Surgery, Department of Surgery, Graduate School of Medicine, Osaka University, Osaka, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Miyazaki
authors.forename: Kiyokazu
authors.initials: K
authors.lastname: Nakajima
authors.forename: Yukinori
authors.initials: Y
authors.lastname: Kurokawa
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Takahashi
authors.forename: Shuji
authors.initials: S
authors.lastname: Takiguchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Miyata
authors.forename: Makoto
authors.initials: M
authors.lastname: Yamasaki
authors.forename: Seiichi
authors.initials: S
authors.lastname: Hirota
authors.forename: Toshirou
authors.initials: T
authors.lastname: Nishida
authors.forename: Masaki
authors.initials: M
authors.lastname: Mori
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Doki
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005743:Gastrectomy / Q000379:methods; D005753:Gastric Mucosa / Q000473:pathology* / Q000601:surgery; D046152:Gastrointestinal Stromal Tumors / Q000473:pathology / Q000601:surgery; D006801:Humans; D010535:Laparoscopy / Q000379:methods; D008297:Male; D008875:Middle Aged; D009442:Neurilemmoma / Q000473:pathology / Q000601:surgery; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000473:pathology* / Q000601:surgery; D013997:Time Factors; D016896:Treatment Outcome; D047368:Tumor Burden; D057832:Watchful Waiting
keywords: GIST; Gastrointestinal stromal tumour; Guidelines; Incidental GIST; Laparoscopic surgery; Mitosis; NCCN; Risk stratification; Submucosal tumour