title: Endoscopic submucosal dissection for colorectal neoplasia: possibility of standardization.
abstract: BACKGROUND
  Endoscopic submucosal dissection (ESD) has been positively applied to and gradually standardized for early stomach cancer, particularly in Japan. However, because it is technically difficult to perform ESD of the colon, ESD is not a commonly used technique.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the possibility of standardizing colorectal ESD.
  
  
  METHODS
  ESD was performed at the Department of Endoscopy, Hiroshima University Hospital.
  
  
  METHODS
  Time required for ESD, rate of complete en bloc resection, complication, and postoperative local persistence and recurrence were investigated retrospectively in 70 cases of colorectal neoplasia, wherein the lesion was more than 20 mm in diameter.
  
  
  METHODS
  All lesions were resected by ESD.
  
  
  RESULTS
  The average (+/-SD) time required for ESD was 70.5+/-45.9 minutes (range, 15-180 minutes), and the histologic rate of complete en bloc resection was 80.0% (56/70). With regard to complication, 1.4% of cases of postoperative hemorrhage (1/70) and 10.0% of cases of perforation (7/70) were observed in total. The rate of perforation was investigated with respect to the type of knife used for ESD and the period after the induction of ESD. The rate of perforation markedly decreased with the practice of the technique. Moreover, the rate of perforation was high when an insulated-tip diathermic knife was used; practicing this technique was insufficient to reduce the rate of perforation. The average duration of follow-up was 614+/-289.5 days, and no case of local persistence and recurrence or metastasis was observed.
  
  
  CONCLUSIONS
  The ESD technique depends on the level of each skill of each colonoscopist.
  
  
  CONCLUSIONS
  With regard to ESD of the colon, complication, eg, perforation, could be decreased by sufficient practice and selection of an appropriate knife. It is suggested that, in the near future, ESD will be standardized for the colon.
authors.affiliation: Department of Endoscopy, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Tanaka
authors.forename: Shiro
authors.initials: S
authors.lastname: Oka
authors.forename: Iwao
authors.initials: I
authors.lastname: Kaneko
authors.forename: Mayuko
authors.initials: M
authors.lastname: Hirata
authors.forename: Ritsuo
authors.initials: R
authors.lastname: Mouri
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kanao
authors.forename: Shigeto
authors.initials: S
authors.lastname: Yoshida
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Chayama
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000601:surgery*; D000368:Aged; D000369:Aged, 80 and over; D003113:Colonoscopy / Q000379:methods* / Q000592:standards; D015179:Colorectal Neoplasms / Q000473:pathology / Q000601:surgery*; D004210:Dissection / Q000295:instrumentation / Q000379:methods* / Q000592:standards; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D012189:Retrospective Studies; D016896:Treatment Outcome