title: Local resection compared with radical resection in the treatment of T1N0M0 rectal adenocarcinoma: a systematic review and meta-analysis.
abstract: BACKGROUND
  Local resection for early rectal cancer is thought to be less invasive but oncologically inferior to radical resection.
  
  
  OBJECTIVE
  The aim of this study was to compare local with radical resection in terms of oncologic control (survival and local recurrence), postoperative complications, and the need for a permanent stoma in adult patients with T1N0M0 rectal adenocarcinoma.
  
  
  METHODS
  Data were retrieved from Medline, Embase, Central, www.clinicaltrials.gov, and conference proceedings.
  
  
  METHODS
  Two reviewers independently screened studies and assessed the risk of bias.
  
  
  METHODS
  Local resection (transanal procedures, excluding endoscopic polypectomy) versus radical resection were considered.
  
  
  METHODS
  The primary outcomes measured were overall survival, major postoperative complications, and the 'need for permanent stoma.'
  
  
  RESULTS
  : One randomized controlled trial and 12 observational studies contributed 2855 patients for analysis. The randomized controlled trial was inadequately powered. Observational study meta-analysis showed that local resection was associated with significantly lower 5-year overall survival (72 more deaths per 1000 patients; 95%CI 30-120). However, the transanal endoscopic microsurgery subgroup did not yield significantly lower overall survival than radical resection. Local resection was associated with higher local recurrence but with lower perioperative mortality (relative risk 0.31, 95% CI 0.14-0.71), major postoperative complications (relative risk 0.20, 95% CI 0.10-0.41), and need for a permanent stoma (relative risk 0.17, 95% CI 0.09-0.30). Findings were robust to sensitivity analyses. Meta-regression suggests that the higher overall survival associated with radical resection may be explained by increased use of local resection on tumors in the lower third of the rectum, which have poorer prognosis.
  
  
  CONCLUSIONS
  This systematic review of nonrandomized studies had inherent biases that may persist despite our rigorous use of systematic review methodology and sensitivity analyses.
  
  
  CONCLUSIONS
  Local resection does not offer oncologic control comparable to radical surgery. However, this finding may be driven by the higher prevalence of cancers with poorer prognosis in local resection groups. Local resection is associated with lower postoperative complications, mortality, and the need for a permanent stoma. Local resection with transanal endoscopic microsurgery appears to offer oncologic control similar to that of radical resection while offering all the benefits of local resection.
authors.affiliation: 1 Department of Surgery, Western University, London, Ontario, Canada 2 School of Population and Public Health, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Biniam
authors.initials: B
authors.lastname: Kidane
authors.forename: Sami A
authors.initials: SA
authors.lastname: Chadi
authors.forename: Steve
authors.initials: S
authors.lastname: Kanters
authors.forename: Patrick H
authors.initials: PH
authors.lastname: Colquhoun
authors.forename: Michael C
authors.initials: MC
authors.lastname: Ott
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D013505:Digestive System Surgical Procedures / Q000401:mortality; D006801:Humans; D009367:Neoplasm Staging; D011183:Postoperative Complications; D011351:Proctoscopy; D012004:Rectal Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D015996:Survival Rate