title: Assessment of outcomes in partial nephrectomy incorporating detailed functional analysis.
abstract: OBJECTIVE
  To assess perioperative morbidity and margins after conventional clamped partial nephrectomy (PN) while also using volumetric analysis to differentiate the contributions of parenchymal volume loss and recovery from ischemia.
  
  
  METHODS
  The study analyzed 163 patients who underwent PN with appropriate studies to allow analysis of function and parenchymal mass specifically in the operated kidney. Recovery from ischemia (glomerular filtration rate saved/volume saved) would be 100% if all nephrons recovered from ischemia. Precision (postoperative parenchymal volume/predicted parenchymal volume, presuming loss of a 5-mm rim of parenchyma related to excision and reconstruction) reflects efforts to optimize the amount of vascularized parenchyma saved with the PN. Trifecta was defined as negative margins, no Clavien grade 3-5 or urologic complications, and both recovery ≥80% and precision ≥80%.
  
  
  RESULTS
  An open procedure was performed in 82 patients (50%), and 59 (36%) had a solitary kidney. Warm ischemia was used in 96 patients (59%). The RENAL nephrometry score (radius, exophytic/endophytic properties of the tumor, nearness of tumor deepest portion to the collecting system or sinus, anterior/posterior descriptor, and the location relative to polar lines) was intermediate in 74 (45%) and high complexity in 38 (23%). Median recovery from ischemia was 95% and was ≥80% in 143 patients (88%). Median precision of excision/reconstruction was 93% and was ≥80% in 138 patients (85%). All tumors had negative surgical margins. Perioperative complications occurred in 13 patients (9%). Trifecta was achieved in 113 patients (69%). Multivariable analysis identified solitary kidney as the only significant predictor of trifecta.
  
  
  CONCLUSIONS
  Given careful patient selection and commensurate surgical expertise, excellent outcomes can be obtained with conventional clamped PN. Analysis of parenchymal volumes is necessary to facilitate comprehensive evaluation of functional outcomes after PN, allowing differentiation of nephron loss vs failure to recover from ischemia.
authors.affiliation: Center for Urologic Oncology, Glickman Urological & Kidney Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Toshio
authors.initials: T
authors.lastname: Takagi
authors.affiliation: Center for Urologic Oncology, Glickman Urological & Kidney Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Maria C
authors.initials: MC
authors.lastname: Mir
authors.affiliation: Center for Urologic Oncology, Glickman Urological & Kidney Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Rebecca A
authors.initials: RA
authors.lastname: Campbell
authors.affiliation: Imaging Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Nidhi
authors.initials: N
authors.lastname: Sharma
authors.affiliation: Center for Urologic Oncology, Glickman Urological & Kidney Institute, Cleveland Clinic, Cleveland, OH; Imaging Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Erick M
authors.initials: EM
authors.lastname: Remer
authors.affiliation: Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Li
authors.affiliation: Center for Urologic Oncology, Glickman Urological & Kidney Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Sevag
authors.initials: S
authors.lastname: Demirjian
authors.affiliation: Center for Urologic Oncology, Glickman Urological & Kidney Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Jihad H
authors.initials: JH
authors.lastname: Kaouk
authors.affiliation: Center for Urologic Oncology, Glickman Urological & Kidney Institute, Cleveland Clinic, Cleveland, OH. Electronic address: campbes3@ccf.org.
authors.forename: Steven C
authors.initials: SC
authors.lastname: Campbell
mesh_terms: D000368:Aged; D015331:Cohort Studies; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007511:Ischemia / Q000473:pathology; D007668:Kidney / Q000502:physiology / Q000601:surgery; D007677:Kidney Function Tests; D007680:Kidney Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009392:Nephrectomy / Q000379:methods*; D009399:Nephrons / Q000601:surgery; D059035:Perioperative Period; D015203:Reproducibility of Results; D016896:Treatment Outcome; D052096:Warm Ischemia