Robot-assisted Partial Nephrectomy for Hilar Tumors: Perioperative Outcomes

Abstract

To compare perioperative outcomes of robot-assisted partial nephrectomy (RAPN) for hilar vs nonhilar tumors. The study retrospectively reviewed 364 patients with available computed tomography scans undergoing RAPN. Demographic data and perioperative outcomes results were compared between the hilar (group 1, n= 70) and nonhilar tumors (group 2, n= 294). Multivariate analysis was used to identify predictors of warm ischemia time (WIT), estimated blood loss (EBL), major perioperative complications, and postoperative renal function. There were no differences with respect to demographic variables. Hilar tumors had higher RENAL (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) scores (P<.001) and were larger (3.9 vs 2.6 cm, P<.001). Surgeries for hilar tumors were associated with greater operative time (210 vs 180 minutes, P<.001), longer WIT (27 vs 17minutes, P<.001), and increased EBL (250 vs 200 mL, P= .04). No differences were noted in transfusion rate, length of stay, complications (overall and major) and positive margins. Postoperative estimated glomerular filtration rate showed no significant difference between hilar vs nonhilar patients on postoperative day 3 (70.12 vs 74.71 mL/min/1.73 m(2), P= .31) or at last follow-up (72.62 vs 75.78 mL/min/1.73 m(2), P= .40), respectively. Multivariate analysis found hilar location was independently associated with increased WIT without significant changes in EBL, major complications, or postoperative renal function. RAPN represents a safe and effective procedure for hilar tumors. Hilar location for patients undergoing RAPN in a high-volume institution seems not be associated with an increased risk of transfusions, major complications, or decline of early postoperative renal function.