title: A multicenter long-term study of imatinib treatment for Japanese patients with unresectable or recurrent gastrointestinal stromal tumors.
abstract: OBJECTIVE
  This multicenter study, which was conducted in northern Kanto, Japan, aimed to assess the efficacy of imatinib mesylate against advanced or recurrent gastrointestinal stromal tumors (GIST).
  
  
  METHODS
  The clinicopathological data of 234 GIST patients who were treated at one of the 11 participating hospitals from 2001-2011 were retrospectively reviewed. Imatinib was administered as a first-line therapy in cases involving unresectable disease or postoperative recurrence (41 cases). The median follow-up period was 4.0 years.
  
  
  RESULTS
  After a median follow-up period of 4.0 years, the patients treated with imatinib (n = 41) exhibited 1-, 3-, and 5-year overall survival (OS) rates of 92.3%, 74.9%, and 53.8%, respectively. In univariate and multivariate analyses, imatinib dose reduction and achieving a complete or partial response were found to be associated with increased OS.
  
  
  CONCLUSIONS
  Long-term imatinib treatment is recommended for patients with non-progressive disease. If patients experience significant toxicities, temporary dose reduction might be useful.
authors.affiliation: Department of General Surgical Science, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: Kyoichi
authors.initials: K
authors.lastname: Ogata
authors.forename: Erito
authors.initials: E
authors.lastname: Mochiki
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Ojima
authors.forename: Norihiro
authors.initials: N
authors.lastname: Haga
authors.forename: Minoru
authors.initials: M
authors.lastname: Fukuchi
authors.forename: Ryuusuke
authors.initials: R
authors.lastname: Aihara
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ando
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Uchida
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Toyomasu
authors.forename: Masaki
authors.initials: M
authors.lastname: Suzuki
authors.forename: Akiharu
authors.initials: A
authors.lastname: Kimura
authors.forename: Norimichi
authors.initials: N
authors.lastname: Kogure
authors.forename: Takehiko
authors.initials: T
authors.lastname: Yokobori
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Ohno
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kuwano
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001549:Benzamides / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D046152:Gastrointestinal Stromal Tumors / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D006801:Humans; D000068877:Imatinib Mesylate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D010879:Piperazines / Q000009:adverse effects / Q000627:therapeutic use*; D011743:Pyrimidines / Q000009:adverse effects / Q000627:therapeutic use*; D012189:Retrospective Studies
chemical_list: D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate
keywords: GIST; imatinib; recurrence