title: Comparison of robot-assisted and open partial nephrectomy for completely endophytic renal tumours: a single centre experience.
abstract: OBJECTIVE
  To compare outcomes between robot-assisted partial nephrectomy (RAPN) and open PN (OPN) for completely endophytic renal tumours.
  
  
  METHODS
  We retrospectively reviewed 1 230 consecutive cases, consisting of 823 RAPNs and 407 OPNs, performed for renal mass at a single academic tertiary centre between 2011 and 2016. Of these, data on 87 RAPN and 56 OPN cases for completely endophytic renal tumours were analysed. Patient and tumour characteristics, operative, postoperative, functional, and oncological outcomes were compared between groups.
  
  
  RESULTS
  Apart from a higher prevalence of solitary kidney among OPN cases (RAPN, 5.7% vs OPN, 21.4%; P = 0.005), demographic characteristics were similar between the groups. There were no statistically significant differences in tumour size (P = 0.07), tumour stage (P = 0.3), margin status (P = 0.48), malignant tumour subtypes (P = 0.51), and grades (P = 0.61) between the groups. Also, there were no statistically significant differences among the groups for warm ischaemia time (P = 0.15), cold ischaemia time (P = 0.28), and intraoperative (P = 0.75) or postoperative (Clavien-Dindo Grade I-V, P = 0.08; Clavien-Dindo Grade III-V, P = 0.85) complication rates. The patients in the RAPN group had a shorter length of stay (P < 0.001), less estimated blood loss (P < 0.001), and lower intraoperative transfusion rates (0% vs 7.1%, P = 0.02). No local recurrences occurred during a median (interquartile range) follow-up of 15.2 (7-27.2) and 18.1 (8.2-30.9) months in the RAPN and OPN groups, respectively. There was no difference in estimated glomerular filtration rate preservation rates between groups for the early (P = 0.26) and latest (P = 0.22) functional follow-up.
  
  
  CONCLUSIONS
  For completely endophytic renal tumours, both OPN and RAPN have excellent outcomes when performed by experienced surgeons at a high-volume centre. For skilled robotic surgeons, RAPN is a safe and effective alternative to OPN with the advantages of shorter length of stay and less blood loss.
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Onder
authors.initials: O
authors.lastname: Kara
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Matthew J
authors.identifier: http://orcid.org/0000-0002-0324-8795
authors.initials: MJ
authors.lastname: Maurice
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Ercan
authors.initials: E
authors.lastname: Malkoc
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Ramirez
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Nelson
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Caputo
authors.affiliation: Department of Urology, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Stein
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
mesh_terms: D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000379:methods*; D012189:Retrospective Studies; D065287:Robotic Surgical Procedures
keywords: endophytic tumours; nephrectomy; partial nephrectomy; robotic surgical procedures