Off-Clamp Laparoscopic Partial Nephrectomy for Hilar Tumors: Oncologic and Renal Functional Outcomes

Abstract

To present our experience demonstrating the feasibility of off-clamp laparoscopic partial nephrectomy (LPN) for hilar tumors and evaluate intermediate oncologic and renal functional outcomes. A retrospective review of LPN cases in nine patients was performed. Hilar lesions were defined as renal cortical tumors in direct physical contact with the renal artery, vein, or both as identified on preoperative imaging and confirmed intraoperatively. Although the renal hilum vasculature was isolated for possible clamping if needed, tumor extirpation was performed off-clamp, eliminating warm ischemia time (WIT). The clinicopathologic parameters, perioperative course, complications, and long-term oncologic and renal functional outcomes were analyzed. Nine patients underwent off-clamp LPN for complex hilar tumors. The mean age was 60.5 years, mean American Society of Anesthesiologists physical classification (ASA) score was 2, and mean BMI was 27.7 kg/m(2). The mean tumor size and volume were 3.2 cm and 35.8 cm(3), respectively. A greater proportion of the tumors (55.6%) were endophytic and mostly of clear cell histology (78%). The mean operative time was 131 minutes, estimated blood loss 250 cc, need for transfusion 0%, and complication rates 22%. No positive margins were present intraoperatively or on final pathology. After a median follow-up of 42.8 months, there was no evidence of clinical or radiographic recurrence in any patient. There was no change in the mean estimated glomerular filtration rate preoperatively and at a median follow-up of 32 months (97.2 mL/minute vs 81.3 mL/minute; p=0.052). Complex renal hilar tumors can be successfully managed with laparoscopic nephron-sparing surgery with elimination of WIT with preservation of perioperative, renal functional, and oncologic outcomes.