title: Clinical outcomes of endoscopic submucosal dissection for large colorectal neoplasms: a comparison of protruding and laterally spreading tumors.
abstract: OBJECTIVE
  The therapeutic outcome of endoscopic submucosal dissection (ESD) for large protruding tumors has not yet been evaluated. We aimed to compare the outcomes of ESD in protruding tumors with those of laterally spreading tumors (LSTs).
  
  
  METHODS
  Endoscopic submucosal dissection was attempted in 218 patients with 220 colorectal tumors ≥30 mm in diameter (67, protruding tumors; 153, LSTs) from July 2007 to June 2014. We retrospectively reviewed patient medical records, therapeutic outcomes, and procedure-related adverse events. This study defined lesions with a height of 10 mm or more as protruding tumors and those with a height under 10 mm as LSTs.
  
  
  RESULTS
  The mean lesion diameter, height, and volume were 43.8, 9.5 mm, and 13.6 cm(3), respectively. The mean procedure time was 75.5 min. Deep submucosal cancer was more frequent in protruding tumors than in LSTs (11.9 vs. 2.6%, P = 0.005). Severe fibrosis was more common in protruding tumors than in LSTs (19.4 vs. 3.9%, P < 0.001). En bloc resection and complete resection rates were lower in protruding tumors than in LSTs (en bloc resection, 76.1 vs. 92.8%, P = 0.001; complete resection, 64.2 vs. 79.1%, P = 0.020). Intra- and post-procedural bleeding were more frequent in protruding tumors than in LSTs (22.4 vs. 2.6%, P < 0.001; 6.0 vs. 0.7%, P = 0.031, respectively). By multivariate analysis, protruding tumor morphology (odds ratio 1.919, P = 0.048) and tumor size ≥60 mm (odds ratio 2.490, P = 0.030) were associated with incomplete resection.
  
  
  CONCLUSIONS
  Endoscopic submucosal dissection for protruding tumors is less effective than ESD for LSTs, with lower rate of complete resection occurring with protruding tumors.
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Jung Ho
authors.initials: JH
authors.lastname: Bae
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea. dhyang@amc.seoul.kr.
authors.forename: Dong-Hoon
authors.initials: DH
authors.lastname: Yang
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Jae Yeon
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Jae Seung
authors.initials: JS
authors.lastname: Soh
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Seohyun
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Ho-Su
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Hyo Jeong
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Sang Hyoung
authors.initials: SH
authors.lastname: Park
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Kyung-Jo
authors.initials: KJ
authors.lastname: Kim
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Byong Duk
authors.initials: BD
authors.lastname: Ye
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Seung-Jae
authors.initials: SJ
authors.lastname: Myung
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Suk-Kyun
authors.initials: SK
authors.lastname: Yang
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Gastroenterology, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea. jsbyeon@amc.seoul.kr.
authors.forename: Jeong-Sik
authors.initials: JS
authors.lastname: Byeon
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000473:pathology / Q000601:surgery*; D004210:Dissection / Q000009:adverse effects / Q000379:methods*; D004724:Endoscopy / Q000009:adverse effects / Q000379:methods*; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: Colorectal neoplasm; ESD; Laterally spreading tumor; Protruding tumor