title: Transanal endoscopic microsurgery versus standard transanal excision for the removal of rectal neoplasms: a systematic review and meta-analysis.
abstract: BACKGROUND
  Transanal endoscopic microsurgery is the intraluminal excision of rectal lesions with the use of instrumentation to maintain a stable pneumorectum, enabling a magnified view of the target lesion. Despite suggested benefits over traditional transanal excision, there is no consensus on which technique is superior.
  
  
  OBJECTIVE
  The aim of the current study is to use meta-analytical techniques to compare transanal endoscopic microsurgery with transanal excision.
  
  
  METHODS
  A comprehensive literature search of PubMed, Embase, and The Cochrane Library was performed.
  
  
  METHODS
  All studies comparing transanal endoscopic microsurgery with transanal excision were included.
  
  
  METHODS
  Transanal endoscopic microsurgery was compared with transanal excision by using random-effects methods to combine data. Data are presented as ORs with 95% CIs.
  
  
  METHODS
  The main outcomes measured were postoperative complication rate, negative microscopic margin rate, specimen fragmentation rate, and lesion recurrence.
  
  
  RESULTS
  Six comparative series comparing outcomes following 927 local excisions were identified. There was no difference between techniques in postoperative complication rate (OR, 1.018; 95% CI, 0.658-1.575; p = 0.937). Transanal endoscopic microsurgery had a higher rate of negative microscopic margins in comparison with transanal excision (OR, 5.281; 95% CI, 3.201-8.712; p < 0.001). Transanal endoscopic microsurgery had a reduced rate of specimen fragmentation (OR, 0.096; 95% CI, 0.044-0.209; p < 0.001) and lesion recurrence (OR, 0.248; 95% CI, 0.154-0.401; p < 0.001) compared with transanal excision. There was no across-study heterogeneity for any end point.
  
  
  CONCLUSIONS
  Most studies were retrospectively designed, and there were variations in patient populations and duration of follow-up.
  
  
  CONCLUSIONS
  Available data are limited because of a lack of randomized controlled trials. However, based on current evidence, transanal endoscopic microsurgery is oncologically superior to transanal excision for the excision of rectal neoplasms.
authors.affiliation: 1Centre for Colorectal Disease, St Vincent's University Hospital, Dublin, Ireland 2Center for Colon & Rectal Surgery, Florida Hospital, Orlando, Florida 3School of Medicine and Medical Sciences, University College Dublin, Ireland.
authors.forename: Cillian
authors.initials: C
authors.lastname: Clancy
authors.forename: John P
authors.initials: JP
authors.lastname: Burke
authors.forename: Mathew R
authors.initials: MR
authors.lastname: Albert
authors.forename: P Ronan
authors.initials: PR
authors.lastname: O'Connell
authors.forename: Desmond C
authors.initials: DC
authors.lastname: Winter
mesh_terms: D000236:Adenoma / Q000473:pathology / Q000601:surgery*; D002277:Carcinoma / Q000473:pathology / Q000601:surgery*; D018572:Disease-Free Survival; D006801:Humans; D008866:Microsurgery / Q000379:methods*; D011351:Proctoscopy / Q000379:methods*; D012004:Rectal Neoplasms / Q000473:pathology / Q000601:surgery*; D012007:Rectum / Q000601:surgery*; D016896:Treatment Outcome