title: Positive surgical margins and local recurrence after simple enucleation and standard partial nephrectomy for malignant renal tumors: systematic review of the literature and meta-analysis of prevalence.
abstract: BACKGROUND
  The definition of the safest width of healthy renal margin to achieve oncological efficacy and therefore of the safest resection technique (RT) during partial nephrectomy (PN) continues to be widely debated. The aim of this study is to evaluate the prevalence of positive surgical margins (PSM), loco-regional recurrence (LRR) and renal recurrence (RER) rates after simple enucleation (SE) and standard partial nephrectomy (SPN) for malignant renal tumors.
  
  
  METHODS
  A systematic review of the English-language literature was performed through August 2016 using the Medline, Web of Science and Embase databases according to the PRISMA criteria. A systematic review and meta-analysis was performed in those studies that defined the exact anatomical location of recurrence after PN.
  
  
  RESULTS
  Overall, 33 studies involving 11,282 patients were selected for quantitative analysis. At a median follow-up of 43 (SE) and 52 (SPN) months, the pooled estimates of the prevalence of PSMs, LRR and RER were 2.7% (95% CI: 1.5-4.6%, P<0.001) and 0.4% (95% CI: 0.1-2.2%, P=0.018), 2.0% (95% CI: 1.4-2.8%, P<0.001) and 0.9% (95% CI: 0.5-1,7%, P=0.04), 1.5% (95% CI: 0.9-2.3%, P=0.001) and 0.9% (95% CI: 0.5-1,7%, P=0.40) in patients undergoing SPN and SE, respectively.
  
  
  CONCLUSIONS
  Our systematic analysis and meta-analysis demonstrates that SE is noninferior to SPN regarding PSM, LRR and RER rates in patients undergoing PN for malignant renal tumors. Further studies using standardized reporting tools are needed to evaluate the role of resection techniques for oncologic outcomes after PN.
authors.affiliation: Department of Urology, Careggi Hospital, University of Florence, Florence, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Minervini
authors.affiliation: Department of Urology, Careggi Hospital, University of Florence, Florence, Italy - riccardo.campi@gmail.com.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Campi
authors.affiliation: Department of Urology, Careggi Hospital, University of Florence, Florence, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Sessa
authors.affiliation: Department of Urology, UC San Diego Health System, La Jolla, CA, USA.
authors.forename: Ithaar
authors.initials: I
authors.lastname: Derweesh
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Jihad H
authors.initials: JH
authors.lastname: Kaouk
authors.affiliation: Department of Urology, Careggi Hospital, University of Florence, Florence, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Mari
authors.affiliation: Department of Urology, Urological Science Institute, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Koon H
authors.initials: KH
authors.lastname: Rha
authors.affiliation: Department of Experimental Medicine, Section of Pharmacology &quot;L. Donatelli&quot;, II University of Naples, Naples, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Sessa
authors.affiliation: Department of Urology, University of Eastern Piedmont, Novara, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Volpe
authors.affiliation: Department of Urology, Careggi Hospital, University of Florence, Florence, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Carini
authors.affiliation: Division of Urologic Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Uzzo
mesh_terms: D006801:Humans; D007680:Kidney Neoplasms / Q000453:epidemiology / Q000601:surgery*; D000072662:Margins of Excision; D009364:Neoplasm Recurrence, Local; D009392:Nephrectomy / Q000379:methods*; D016896:Treatment Outcome