gms | German Medical Science

Background: Open partial nephrectomy is still considered today in cases of e.g. centrally localized tumors, infiltration or proximity to the collecting system. With this study we wanted to clarify whether patients in such cases can benefit from a preoperative ureteral stent insertion.

Methods: We identified n= 39 patients who received ureteral stent insertion before partial nephrectomy from 2005–2021. In order to set up a control collective with comparably complex tumors, we determined the RENAL and PADUA score in all patients. After this we set up a control cohort with n= 117 patients, by using 1:3 propensity score matching. The matching parameters were: tumor diameter, RENAL and PADUA score. The median follow-up was 20 months.

Results: No significant differences were found in baseline clinical characteristics. Median tumor size (4.8 cm vs. 4.5 cm; p= 0.17) and T stage (t1b both) were comparable in both collectives. No significant differences were found between this two collectives with regard to tumor complexity (RENAL: median 7 vs 8, p=0,75; PADUA: median 8 vs. 9, p=0,84). Significant differences were found in the incidence of postoperative urinoma (2 (1,7%) vs 4 (10,3%), p=0,016). But no significant differences were found regarding the frequency (10 (40%) vs. 9 (36%) p=0,86) and intensity of postoperative complications.

Conclusions: Preoperative assessment of the complexity of renal tumors for planning the surgical procedure is still challenging. In our collective, patients did not benefit from preoperative ureteral stent insertion. The frequency and intensity of postoperative complications were comparable in both collectives, whereas postoperative urinomas occurred more frequently in patients with preoperative insertion of a ureteral stent. We attribute this to the increased manipulation of the collecting system due to the ureteral stent insertion. Therefore this approach could not recommended as standard operating procedure.