title: Stenosis rates after endoscopic submucosal dissection of large rectal tumors involving greater than three quarters of the luminal circumference.
abstract: Endoscopic submucosal dissection (ESD) is a minimally invasive treatment option for large rectal tumors. There are limited data available on stenosis rates following ESD of large rectal lesions. We aimed to evaluate the stenosis rate following ESD of large rectal tumors with rectal mucosal defects greater than three quarters of the circumference.
  
  
  
  We retrospectively identified patients who underwent rectal ESD between January 1998 and July 2014. Patients with rectal mucosal defects greater than three quarters the luminal circumference were included for analysis. Clinicopathologic characteristics, treatment outcomes and adverse events were assessed. Stenosis was defined as an inability to pass a pediatric colonoscope into the sigmoid colon. None of the patients underwent prophylactic balloon dilation.
  
  
  
  A total of 363 patients with 370 rectal lesions were treated by ESD. Among these, 26 patients had 26 lesions with rectal mucosal defects greater than three quarters of the luminal circumference. Median tumor size (range) was 80 (47-150) mm. Four lesions (15 %) required between 90 and <100 % circumferential dissection, while complete circumferential ESD was performed in two lesions (8 %). Dissection extended to the anal canal in six patients. The median procedure time was 220 min. En bloc resection and curative resection were achieved in 88.5 and 65.4 %, respectively. Delayed bleeding rates and perforation rates were 7.7 and 0 %, respectively. During a median follow-up period of 9.8 (0-59) months, there were no patients with complaints of constipation or fecal incontinence. One patient (4.2 %) was noted to have rectal stenosis, but was clinically asymptomatic. Endoscopic balloon dilation was not required in any patients.
  
  
  
  Stenosis may rarely occur after ESD of large rectal lesions with rectal mucosal defects greater than three quarters of the circumference, even without prophylactic endoscopic balloon dilation.
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan. seabe@ncc.go.jp.
authors.forename: Seiichiro
authors.initials: S
authors.lastname: Abe
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
authors.forename: Taku
authors.initials: T
authors.lastname: Sakamoto
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Takamaru
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Yamada
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakajima
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
authors.forename: Takahisa
authors.initials: T
authors.lastname: Matsuda
authors.affiliation: Endoscopy Division, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Saito
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003251:Constriction, Pathologic / Q000453:epidemiology / Q000209:etiology; D000069916:Endoscopic Mucosal Resection; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology / Q000601:surgery; D007415:Intestinal Obstruction / Q000453:epidemiology / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology; D012004:Rectal Neoplasms / Q000473:pathology / Q000601:surgery*; D012007:Rectum / Q000473:pathology / Q000601:surgery*; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: Endoscopic submucosal dissection; Rectal cancer; Stricture