title: Impact of the Japanese gastric cancer screening system on treatment outcomes in gastric gastrointestinal stromal tumor (GIST): an analysis based on the GIST registry.
abstract: BACKGROUND
  Gastrointestinal stromal tumors (GISTs) of the stomach are found incidentally during gastric cancer screening in Japan. This study investigated whether the Japanese gastric cancer screening system helps to improve treatment outcomes in gastric GIST based on an analysis of the GIST registry conducted by the Kinki GIST Study Group.
  
  
  METHODS
  The registry was designed to collect data on background characteristics, treatment methods, pathologic characteristics, and prognosis of GIST from January 2003 through December 2007 at 40 participating institutions.
  
  
  RESULTS
  The study enrolled 672 GIST patients, 482 of whom had gastric GIST. According to the modified National Institutes of Health consensus criteria, 22.6 % of the patients were classified as high risk for recurrence, 18.5 % as intermediate risk, 35.9 % as low risk, and 13.9 % as very low risk. After exclusion of the patients inevaluable for treatment outcome, the study included 137 symptomatic patients (symptomatic group) and 147 asymptomatic patients (asymptomatic group). The diagnosis of the asymptomatic patients was determined through gastric cancer screening. The median tumor size in the asymptomatic group was significantly smaller than in the symptomatic group (3.5 vs. 5.3 cm; P < 0.0001). The 5-year recurrence-free survival rate in the asymptomatic high-risk patients (72.4 %) was lower than in their symptomatic counterparts (46.3 %) (P = 0.017). More patients in the asymptomatic group underwent laparoscopic surgery (42.2 vs. 27.2 %; P = 0.0081).
  
  
  CONCLUSIONS
  By identifying asymptomatic patients, the Japanese gastric cancer screening system contributes to early detection of gastric GIST and favorable treatment outcomes.
authors.affiliation: Department of Surgery, National Hospital Organization Osaka National Hospital, Osaka, Japan, kazuy@onh.go.jp.
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Toshimasa
authors.initials: T
authors.lastname: Tsujinaka
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Takahashi
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Sato
authors.forename: Yukio
authors.initials: Y
authors.lastname: Nishiguchi
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Nakashima
authors.forename: Kazuya
authors.initials: K
authors.lastname: Muguruma
authors.forename: Seiichi
authors.initials: S
authors.lastname: Hirota
authors.forename: Toshiro
authors.initials: T
authors.lastname: Nishida
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D055088:Early Detection of Cancer; D005260:Female; D005500:Follow-Up Studies; D046152:Gastrointestinal Stromal Tumors / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D006801:Humans; D007564:Japan; D010535:Laparoscopy; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D009367:Neoplasm Staging; D011379:Prognosis; D012042:Registries; D012189:Retrospective Studies; D015996:Survival Rate; D055815:Young Adult