title: When Partial Nephrectomy is Unsuccessful: Understanding the Reasons for Conversion from Robotic Partial to Radical Nephrectomy at a Tertiary Referral Center.
abstract: We sought to identify the preoperative factors associated with conversion from robotic partial nephrectomy to radical nephrectomy. We report the incidence of this event.
  
  
  
  Using our institutional review board approved database, we abstracted data on 1,023 robotic partial nephrectomies performed at our center between 2010 and 2015. Standard and converted cases were compared in terms of patients and tumor characteristics, and perioperative, functional and oncologic outcomes. Logistic regression analysis was done to identify predictors of radical conversion.
  
  
  
  The overall conversion rate was 3.1% (32 of 1,023 cases). The most common reasons for conversion were tumor involvement of hilar structures (8 cases or 25%), failure to achieve negative margins on frozen section (7 or 21.8%), suspicion of advanced disease (5 or 15.6%) and failure to progress (5 or 15.6%). Patients requiring conversion were older and had a higher Charlson score (both p <0.01), including an increased prevalence of chronic kidney disease (p = 0.02). Increasing tumor size (5 vs 3.1 cm, p <0.01) and R.E.N.A.L. (radius, exophytic/endophytic properties, nearness of tumor to collecting system or sinus, anterior/posterior, location relative to polar lines and hilar location) score (9 vs 8, p <0.01) were also associated with an increased risk of conversion. Worse baseline renal function (OR 0.98, 95% CI 0.96-0.99, p = 0.04), large tumor size (OR 1.44, 95% CI 1.22-1.7, p <0.01) and increasing R.E.N.A.L. score (p = 0.02) were independent predictors of conversion. Compared to converted cases, at latest followup standard robotic partial nephrectomy cases had similar short-term oncologic outcomes but better renal functional preservation (p <0.01).
  
  
  
  At a high volume center the rate of robotic partial nephrectomy conversion to radical nephrectomy was 3.1%, including 2.2% of preoperatively anticipated nephrectomy cases. Increasing tumor size and complexity, and poor preoperative renal function are the main predictors of conversion.
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio; Urology Department, Amasya University Medical School, Amasya, Turkey.
authors.forename: Önder
authors.initials: Ö
authors.lastname: Kara
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Maurice
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Pascal
authors.initials: P
authors.lastname: Mouracade
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Ercan
authors.initials: E
authors.lastname: Malkoç
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Julien
authors.initials: J
authors.lastname: Dagenais
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Nelson
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Jaya Sai S
authors.initials: JSS
authors.lastname: Chavali
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Stein
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Amr
authors.initials: A
authors.lastname: Fergany
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio. Electronic address: kaoukj@ccf.org.
authors.forename: Jihad H
authors.initials: JH
authors.lastname: Kaouk
mesh_terms: D000367:Age Factors; D000368:Aged; D061887:Conversion to Open Surgery / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000009:adverse effects* / Q000379:methods; D057234:Preoperative Period; D012189:Retrospective Studies; D012307:Risk Factors; D065287:Robotic Surgical Procedures / Q000009:adverse effects* / Q000379:methods; D062606:Tertiary Care Centers / Q000706:statistics & numerical data*; D016896:Treatment Outcome
keywords: conversion to open surgery; kidney; nephrectomy; risk factors; robotic surgical procedures