title: Endoscopic resection therapies for rectal neuroendocrine tumors: a systematic review and meta-analysis.
abstract: OBJECTIVE
  Among various endoscopic resection therapies, including conventional endoscopic mucosal resection (EMR) only with a snare after submucosal injection, modified EMR (m-EMR) with other assistant devices such as a ligation band or a suction cap, and endoscopic submucosal dissection (ESD), we aimed to study which is the best choice for rectal neuroendocrine tumors.
  
  
  METHODS
  A broad literature research was performed, and a systematic review and meta-analysis were conducted.
  
  
  RESULTS
  Ten retrospective studies with 650 patients were included. Complete resection rates were significantly higher in the ESD group compared with the EMR group (relative risk [RR] 0.89, 95% confidence interval [CI] [0.79, 0.99]), in the m-EMR group compared with the conventional EMR group (RR 0.72, 95% CI [0.60, 0.86]), and was comparable between the ESD group and the m-EMR group (RR 1.03, 95% CI [0.95, 1.11]). Procedure time was significantly longer in the ESD group than in the EMR group (standard mean differences -1.37, 95% CI [-1.99, -0.75]), but there was no significant difference between that of the m-EMR group and ESD group (standard mean differences -1.50, 95% CI [-3.14, 0.14]). Local recurrence occurred in five cases in the EMR group (5/328) and did not occur in the ESD group (0/209).
  
  
  CONCLUSIONS
  ESD or m-EMR techniques could be applied to rectal neuroendocrine tumors with indications for endoscopic treatment. m-EMR procedures appear to be comparable with ESD in the treatment of rectal neuroendocrine tumors. However, the findings have to be carefully interpreted due to the lower level of evidence.
authors.affiliation: Department of General Surgery, Peking University Third Hospital, Beijing, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhou
authors.forename: Haiting
authors.initials: H
authors.lastname: Xie
authors.forename: Lingduo
authors.initials: L
authors.lastname: Xie
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Weihua
authors.initials: W
authors.lastname: Cao
authors.forename: Wei
authors.initials: W
authors.lastname: Fu
mesh_terms: D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D006801:Humans; D018358:Neuroendocrine Tumors / Q000601:surgery*; D061646:Operative Time; D019106:Postoperative Hemorrhage / Q000453:epidemiology; D011379:Prognosis; D039781:PubMed; D012004:Rectal Neoplasms / Q000601:surgery*
keywords: endoscopic mucosal resection; endoscopic submucosal dissection; gastrointestinal endoscopy; rectal neuroendocrine tumor