Comparison of functional outcomes of off-clamp laparoscopic partial nephrectomy access techniques: A preliminary report

Objective: This study aims to compare renal functional outcomes of access techniques in patients who underwent off-clamp (Off-C) laparoscopic partial nephrectomy (LPN). Materials and Methods: Thirty-four Off-C LPNs in patients with functioning contralateral kidney from March 2011 to June 2018 were included in the study. Twenty-two patients underwent transperitoneal, 12 patients underwent retroperitoneal Off-C LPN. The primary outcome was glomerular filtration rate changes over time, postoperatively. The secondary outcome was the evaluation of trifecta and pentafecta rate. Results: Preoperative demographics, tumor size (26.59 vs. 22.83mm, p=0.790), RENAL score (5.45 vs. 5.33, p=0.990), operation time (79.95 vs. 81.33 min, p=0.157), blood loss (170.23 vs. 150.83mL, p=0.790) were similar in both groups. Although preservation of renal function was better in group 2 in the early period, similar results were found in both groups at the end of the first year, postoperatively. No positive surgical margin and postoperative major complications were detected in any patient. While trifecta goals were achieved in all the patients in the cohort, pentafecta rates were 90.9% and 91.7% in the transperitoneal and retroperitoneal groups, respectively. Conclusions: Transperitoneal and retroperitoneal access were found to have similar outcomes in terms of preservation of renal function at the end of the first year postoperatively. Off-C LPN may be considered as a safe and effective treatment option in patients having non-complex renal tumors.