title: Endoscopic submucosal dissection for nonampullary large superficial adenocarcinoma/adenoma of the duodenum: feasibility and long-term outcomes.
abstract: OBJECTIVE
  The clinical benefit of endoscopic submucosal dissection (ESD) for superficial duodenal neoplasias has not yet been verified. The aims of this study were to validate the feasibility and long-term outcomes of ESD for nonampullary superficial duodenal neoplasias, larger than 20 mm.
  
  
  METHODS
  41 patients, with 41 nonampullary large superficial duodenal neoplasias, who underwent ESD between April 2005 to March 2013 were included in the study. The short- and long-term outcomes were retrospectively evaluated, related to tumor size, resection size, histological type, invasion depth, complete resection rate, operation time, perforation rate, delayed bleeding rate, local recurrence rate, distant metastasis, and survival rate.
  
  
  RESULTS
  ESD was successfully completed in 38 of 41 patients (92.7 %). The median sizes of tumors and resected specimens were, respectively, 26 mm (range 20 - 70 mm) and 36.5 mm (range 23 - 80 mm). Histopathological findings showed 13 adenocarcinomas (12 mucosal, 1 submucosal) and 28 adenomas (26 high grade dysplasia, 2 low grade dysplasia). The complete resection rate was 89.5 % (34 /38 tumors). The mean operation time was 128.3minutes. Perforation during ESD occurred in 39 % and delayed bleeding occurred in 18.4 %. The median observation period was 48 months (range 3.2 - 94.1 months), and no local recurrence or distant metastasis was seen during this time, representing a disease-free survival rate of 100 %.
  
  
  CONCLUSIONS
  ESD for nonampullary large superficial duodenal adenocarcinoma/adenoma is feasible with favorable long-term outcomes. However, because of the high complication rate due to its technical difficulty, experience and skill of the operator, along with adequate perioperative management, are essential.
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Shu
authors.initials: S
authors.lastname: Hoteya
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan ; Cancer Center, Keio University, Tokyo, Japan.
authors.forename: Naohisa
authors.initials: N
authors.lastname: Yahagi
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Toshiro
authors.initials: T
authors.lastname: Iizuka
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kikuchi
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Mitani
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Matsui
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Ogawa
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yamashita
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Furuhata
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Yamada
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Ryusuke
authors.initials: R
authors.lastname: Kimura
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Nomura
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Kuribayashi
authors.affiliation: Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Kaise