RENAL nephrometry score is associated with operative approach for partial nephrectomy and urine leak

Objective: To identify whether RENAL nephrometry score is associated with partial nephrectomy (PN) technique. RENAL nephrometry score quantifies anatomic characteristics of renal tumors. Data are limited regarding clinical utility for surgical planning. Methods: Multicenter analysis of patients undergoing PN for renal masses from March 2003 to May 2011. Cohort was stratified by surgical modality: open partial nephrectomy (OPN), laparoscopic partial nephrectomy (LPN), and robotic-assisted laparoscopic partial nephrectomy (RALPN). Demographic and clinicopathological variables were compared between groups; RENAL score was calculated from preoperative imaging. Factors associated with choice of treatment modality and urine leak were entered into multivariable models. Results: One hundred fifty-three patients who underwent OPN, 100 patients who underwent LPN, and 31 patients who underwent RALPN were evaluated, the median tumor size (cm) was significantly larger for OPN (OPN 4.2 vs LPN 2.4 vs RALPN 2.0; P <.001); median operative time (minutes) and ischemia time (minutes) were shorter in OPN (OPN 190 and 25 vs LPN 200 and 29 vs RALPN 195 and 30; P =.042 and P <.001). Mean RENAL score was highest in OPN (OPN 8 vs LPN 6.3 vs RALPN 6.4; P <.001). No significant differences were noted in overall/high-grade complication rates (Clavien, P =.441/.985). On multivariate analysis, there was a 55% increased odds of undergoing OPN for each increase in RENAL score (P <.001). Higher RENAL score was associated with increased odds of urine leak (odds ratios [OR], 1.56; P =.002). Conclusion: RENAL nephrometry score was associated with type of surgical approach (open vs laparoscopic/robotic) and urine leak. RENAL score may be useful as a decision-making tool in evaluation of patients for nephron-sparing surgery (NSS). Further investigation is requisite.