An analysis of renal and surgical outcomes of patients with and without preoperative ureteral stenting before Nephron-Sparing Surgery for renal malignancies of higher complexity by using a propensity score-based approach.

Abstract

Introduction: This study aims to evaluate the impact of preoperative ureteral stenting on postoperative outcomes, especially the incidence of urinoma, in patients with complex renal tumors undergoing nephron-sparing surgery.

Methods: A retrospective analysis of 35 patients who received preoperative ureteral stenting prior to nephron-sparing surgery for complex tumors at the University Hospital of Würzburg between 2002 and 2021. A control group of 115 patients was established through 1:3 propensity score matching based on age, gender, T-stage, and RENAL score. Clinical parameters, surgical outcomes, and complications were assessed, and statistical comparisons were performed using the unpaired Student's t-test and chi-square test.

Results: While both groups showed comparable tumor complexity (RENAL: 7 vs 7, p=0.58; PADUA: 9 vs 8, p=0.62), there were no significant differences in median hospital stay (12 vs. 11; p=0.068), surgical time (183 vs. 190 minutes; p=0.37), postoperative haemoglobin levels (11g/dl vs. 11.1d/dl; p=0.9) and renal function (GFR 65 ml/min/m² in both groups). Moreover complication severity during NSS, defined by Clavien-Dindo classification, was similar (none vs. grade I; p=0.29). No significant difference in the rate of urinoma was observed (11% vs. 4%, p=0.93).

Conclusions: This study found no significant benefits of preoperative ipsilateral ureteral stenting on postoperative outcomes, particularly concerning the development of urinoma. Given these findings, preventive ureteral stenting is not recommended prior to partial kidney resection for complex renal tumors.