title: Outcomes of endoscopic submucosal dissection versus endoscopic mucosal resection in management of superficial squamous esophageal neoplasms outside Japan.
abstract: OBJECTIVE
  This study aims to evaluate the outcomes of endoscopic submucosal dissection (ESD) versus endoscopic mucosal resection (EMR) in management of superficial squamous esophageal neoplasms.
  
  
  BACKGROUND
  Endoscopic resection is a potential alternative in treatment of superficial squamous esophageal neoplasms. However, there have been limited reports comparing the outcomes of ESD versus EMR in the treatment of these lesions outside Japan.
  
  
  METHODS
  A retrospective analysis of all patients with high-grade superficial neoplasms (moderate to severe dysplasia and noninvasive carcinoma) or intramucosal carcinoma resected endoscopically between January 2002 and December 2007 was carried out. Clinical and pathologic outcomes were compared.
  
  
  RESULTS
  ESD was done in 22 lesions (18 patients) and cap-EMR in 13 lesions (10 patients). ESD allowed resection of larger lesions indicated by a significantly longer endoscopic length (P=0.015), larger specimen size (P<0.001), and more lesions extending for more than half the circumference of the esophagus (P=0.005) when compared with cap-EMR. ESD also achieved with a higher en bloc resection rate (P=0.052) and lower piecemeal resection rate (P=0.015). Procedure-related morbidities were not significantly different (P=1.0). There was no procedure-related mortality in the entire series.
  
  
  CONCLUSIONS
  ESD allows en bloc resection of larger mucosal lesions of the esophagus, earlier not possible by cap-EMR. This is achievable without significantly increasing the risks to the patient even in low-volume centers outside Japan. Whether ESD decreases the local recurrence and improves survival when compared with cap-EMR will require further long-term follow-up studies.
authors.affiliation: Division of Upper Gastrointestinal Surgery, Department of Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong SAR, China.
authors.forename: Anthony Yuen Bun
authors.initials: AY
authors.lastname: Teoh
authors.forename: Philip Wai Yan
authors.initials: PW
authors.lastname: Chiu
authors.forename: Dennis Kwok
authors.initials: DK
authors.lastname: Yu Ngo
authors.forename: Simon Kin Hung
authors.initials: SK
authors.lastname: Wong
authors.forename: James Yun Wong
authors.initials: JY
authors.lastname: Lau
authors.forename: Enders Kwok Wai
authors.initials: EK
authors.lastname: Ng
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000473:pathology / Q000601:surgery*; D004938:Esophageal Neoplasms / Q000473:pathology / Q000601:surgery*; D016629:Esophagectomy / Q000009:adverse effects / Q000379:methods*; D004945:Esophagoscopy / Q000009:adverse effects / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology; D012189:Retrospective Studies; D016896:Treatment Outcome