title: Risk factors for vertical incomplete resection in endoscopic submucosal dissection as total excisional biopsy for submucosal invasive colorectal carcinoma.
abstract: OBJECTIVE
  Endoscopic submucosal dissection (ESD) for colorectal tumor is a minimally invasive treatment. Histologic information obtained from the entire ESD specimen is important for therapy selection in submucosal invasive colorectal carcinoma (SMca). This study aimed to identify risk factors for vertical incomplete resection (vertical margin-positive [VM+]) when ESD was performed as total excisional biopsy for SMca.
  
  
  METHODS
  From June 2003 through December 2011, 78 SMca cases were resected by ESD at Hiroshima University Hospital. Patient and tumor characteristics, intraoperative variables, and histopathology were compared between the VM+ group and the vertical complete resection (vertical margin-negative) group. The ability of magnifying endoscopy (ME) and endoscopic ultrasonography (EUS) to predict VM+ was assessed.
  
  
  RESULTS
  ESD resulted in VM+ in eight cases (10.3 %), with a greater percentage invading to a depth of ≥2,000 vs. <2,000 μm (P = 0.047). Severe submucosal fibrosis was found in five of the eight cases (62.5 %, P = 0.017). Poor differentiation was seen at the deepest invasive portion in six cases (75.0 %), and two of six cases had an invasion depth <2,000 μm. Of 39 EUS cases, 36 not showing deep invasion close to the muscularis propria were completely resected by ESD.
  
  
  CONCLUSIONS
  Submucosal fibrosis and poor differentiation at the deepest invasive portion may be risk factors for VM+ in colorectal ESD for tumors with submucosal deep invasion. ME plus EUS is more likely to help determine whether ESD is indicated as complete total excisional biopsy for SMca.
authors.affiliation: Department of Endoscopy, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan.
authors.forename: Shun-ichiro
authors.initials: S
authors.lastname: Ozawa
authors.forename: Shinji
authors.initials: S
authors.lastname: Tanaka
authors.forename: Nana
authors.initials: N
authors.lastname: Hayashi
authors.forename: Soki
authors.initials: S
authors.lastname: Nishiyama
authors.forename: Motomi
authors.initials: M
authors.lastname: Terasaki
authors.forename: Koichi
authors.initials: K
authors.lastname: Nakadoi
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kanao
authors.forename: Shiro
authors.initials: S
authors.lastname: Oka
authors.forename: Shigeto
authors.initials: S
authors.lastname: Yoshida
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Chayama
mesh_terms: D000368:Aged; D001706:Biopsy; D003106:Colon / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D004210:Dissection; D019160:Endosonography; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery*; D007430:Intraoperative Care; D008297:Male; D009361:Neoplasm Invasiveness; D012307:Risk Factors; D016896:Treatment Outcome