title: Extent of lymph node dissection and recurrence-free survival after radical cystectomy: a meta-analysis.
abstract: BACKGROUND
  Lymph node dissection (LND) at the time of radical cystectomy (RC) is the standard of care in the treatment of muscle-invasive bladder cancer. However, no final consensus about its optimal extent has been reached.
  
  
  METHODS
  We conducted a meta-analysis to determine the effect of the extent of LND on 5-year recurrence-free survival and its complication rates in patients undergoing RC. A systematic search of MEDLINE, PubMed, and EMBASE has been performed. All studies published until June 2013 and providing information on 5-year recurrence-free survival were included in the analysis.
  
  
  RESULTS
  We analyzed the recurrence-free survival data of 11 studies on standard or extended LND or both in patients undergoing RC. The extended (above the bifurcation of iliac vessels) LND showed a significant trend toward a higher proportion of lymph node-positive patients (odds ratio = 1.39; 95% CI: 0.96-2.00; P = 0.08). Including all studies that compare extended with standard LND, the overall odds ratio for the 5-year recurrence-free survival is 1.63 (95% CI: 1.28-2.07, P<0.001), showing a strong and statistical significant survival benefit for the group of patients who underwent extended LND. Moreover, the weighted average 5-year recurrence-free survival rate of all existing studies on standard LND is significantly different from the ones reporting extended LND rates. No differences in perioperative mortality or complication rates were reported.
  
  
  CONCLUSIONS
  The present meta-analysis provides evidence to the positive effect of extended LND on recurrence-free survival and its diagnostic benefit in patients undergoing RC. Patients who underwent extended LND did not suffer from higher complication rates or perioperative mortality.
authors.affiliation: Division of Visceral and Transplant Surgery, University Hospital of Zurich, Switzerland.
authors.forename: Philipp
authors.initials: P
authors.lastname: Mandel
authors.affiliation: Department of Urology, University of California, Davis, Medical Center, Sacramento, CA. Electronic address: derya.tilki@ucdmc.ucdavis.edu.
authors.forename: Derya
authors.initials: D
authors.lastname: Tilki
authors.affiliation: The Whiteley-Martin Research Centre, Department of Surgery, The University of Sydney, Sydney, Australia.
authors.forename: Guy D
authors.initials: GD
authors.lastname: Eslick
mesh_terms: D015653:Cystectomy / Q000379:methods; D018572:Disease-Free Survival; D006801:Humans; D008197:Lymph Node Excision / Q000379:methods; D008198:Lymph Nodes / Q000473:pathology / Q000601:surgery*; D011379:Prognosis; D016896:Treatment Outcome; D001749:Urinary Bladder Neoplasms / Q000601:surgery*
keywords: Extended LND; Lymph node dissection; Radical cystectomy; Standard LND