title: Endoscopic submucosal dissection for colorectal tumors: technical difficulties and rate of perforation.
abstract: OBJECTIVE
  Endoscopic submucosal dissection (ESD) for colorectal tumors is not generally recommended because of the technical difficulties and complications, including perforation. These aspects of ESD are thoroughly analyzed in our retrospective study.
  
  
  METHODS
  We studied 105 colorectal tumors, from 100 patients, that were treated by ESD at the Kyoto Prefectural University of Medicine or Nara City Hospital between 2005 and 2008. We analyzed tumor size, operation time, rate of en bloc resection, and complications. In addition, we thoroughly investigated the cases of perforation.
  
  
  RESULTS
  The average tumor size was 30.4 mm; average operation time, 102 min; and rate of en bloc resection, 88.5 %. Perforation occurred in 10.4 % of the ESD procedures. Of the 11 perforations, 8 were detected during ESD and treated by clip closure during endoscopy, while 3 were evident only on subsequent routine computed tomography (CT); these were also managed conservatively. A case of postoperative hemorrhage was also observed.
  
  
  CONCLUSIONS
  ESD effectively achieved a high rate of en bloc resection. However, the perforation rate was substantial; hence, improvement in the ESD method is required. The outcomes of ESD, especially for early colorectal malignancies, need to be assessed further.
authors.affiliation: Department of Molecular Gastroenterology and Hepatology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, Kyoto 602-8566, Japan. naohisa@koto.kpu-m.ac.jp
authors.forename: N
authors.initials: N
authors.lastname: Yoshida
authors.forename: N
authors.initials: N
authors.lastname: Wakabayashi
authors.forename: K
authors.initials: K
authors.lastname: Kanemasa
authors.forename: Y
authors.initials: Y
authors.lastname: Sumida
authors.forename: D
authors.initials: D
authors.lastname: Hasegawa
authors.forename: K
authors.initials: K
authors.lastname: Inoue
authors.forename: Y
authors.initials: Y
authors.lastname: Morimoto
authors.forename: A
authors.initials: A
authors.lastname: Kashiwa
authors.forename: H
authors.initials: H
authors.lastname: Konishi
authors.forename: N
authors.initials: N
authors.lastname: Yagi
authors.forename: Y
authors.initials: Y
authors.lastname: Naito
authors.forename: A
authors.initials: A
authors.lastname: Yanagisawa
authors.forename: T
authors.initials: T
authors.lastname: Yoshikawa
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003110:Colonic Neoplasms / Q000601:surgery*; D004210:Dissection / Q000379:methods*; D016099:Endoscopy, Gastrointestinal / Q000009:adverse effects / Q000379:methods*; D005260:Female; D006801:Humans; D007416:Intestinal Perforation / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology; D012004:Rectal Neoplasms / Q000601:surgery*; D012189:Retrospective Studies