title: Early Outcomes of Endoscopic Submucosal Dissection for Colorectal Neoplasms According to Clinical Indications.
abstract: BACKGROUND
  Although endoscopic submucosal dissection has been shown to be safe and effective for colorectal tumors, its clinical outcomes vary.
  
  
  OBJECTIVE
  The aim of this study is to assess the outcomes of endoscopic submucosal dissection according to clinical indications.
  
  
  METHODS
  This is a prospective, multicenter, single-arm study.
  
  
  METHODS
  The study was conducted at special hospitals for colorectal diseases and cancers.
  
  
  METHODS
  The study population included consecutive patients aged 20 to 80 years who underwent colorectal endoscopic submucosal dissection for 1) early colorectal cancer, 2) laterally spreading tumors ≥2 cm in diameter, and 3) submucosal tumors.
  
  
  METHODS
  Procedures were performed by experienced colonoscopists.
  
  
  METHODS
  The primary end points were en bloc and curative resection rates. En bloc resection was defined as endoscopic one-piece resection without tumor fragmentation. Curative resection was defined as en bloc resection and no pathologic requirement for additional surgery. Secondary end points included procedure time, complications, and hospital stay.
  
  
  RESULTS
  Of 321 patients, 317 (98.8%) underwent en bloc resection and 231 (72.0%) underwent curative resection. The mean procedure time was 46.2 minutes. Mean hospital stay after the procedure was 3.1 days. Perforation occurred in 2 patients (0.6%), and bleeding occurred in 10 (3.1%) patients. All patients with complications were treated by endoscopic clipping or nonoperative management. Fifteen patients (4.7%) underwent additional radical surgery owing to the risks of lymph node metastasis. Although tumor size was smaller and procedure time shorter in the submucosal tumor group than in the laterally spreading tumor or early colorectal cancer group, there were no differences in clinical outcomes including en bloc and curative resection rates. Submucosal fibrosis was the only factor affecting endoscopic submucosal dissection procedure-related complications.
  
  
  CONCLUSIONS
  Early outcomes in a limited population and the potential for selection bias were limitations of this study.
  
  
  CONCLUSIONS
  Outcomes of colorectal endoscopic submucosal dissection were acceptable in selected patients, with no difference in outcomes according to clinical indications. Because submucosal fibrosis can increase complications, it should be minimized before endoscopic submucosal dissection.
authors.affiliation: 1 Department of Surgery, Daehang Hospital, Seoul, Korea 2 Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea 3 Department of Pathology, Daehang Hospital, Seoul, Korea.
authors.forename: Eui-Gon
authors.initials: EG
authors.lastname: Youk
authors.forename: Dae Kyng
authors.initials: DK
authors.lastname: Sohn
authors.forename: Chang Won
authors.initials: CW
authors.lastname: Hong
authors.forename: Seong Dae
authors.initials: SD
authors.lastname: Lee
authors.forename: Kyung Su
authors.initials: KS
authors.lastname: Han
authors.forename: Byung Chang
authors.initials: BC
authors.lastname: Kim
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Chang
authors.forename: Mi-Jung
authors.initials: MJ
authors.lastname: Kim
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003106:Colon / Q000473:pathology / Q000601:surgery*; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000473:pathology / Q000601:surgery*; D004210:Dissection / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology / Q000601:surgery*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012007:Rectum / Q000473:pathology / Q000601:surgery*; D016896:Treatment Outcome