Transperitoneal versus retroperitoneal approach does not alter arterial clamping strategy during robot-assisted partial nephrectomy: interim results from the multicentric PODRACING randomized controlled trial

Introduction Two anatomical approaches can be used to access a kidney tumor —and the associated renal hilum— during robot-assisted partial nephrectomy (RAPN): the transperitoneal (TP) and retroperitoneal (RP) approaches. Herein, we investigate whether the surgical approach has an impact on the performed clamping strategy: selective clamping (SC) vs main-artery clamping (MAC) and if a planned clamping strategy is performed equally accurate in both approaches. Furthermore, we look at total operative time and the occurrence of intraoperative and early postoperative complications in both approaches. Methods Data from the interim analysis of the multicenter PODRACING randomized controlled trial (NCT06536439) was used, where patients undergo RAPN with or without a 3D perfusion zone (3DPZ) model. The study was approved by the Belgian Federal Agency for Medicines and Health Products (CIV-23-11-044854). TP surgery was performed with Da Vinci X or Xi systems, RP with Xi or SP systems (Intuitive Surgical, California, USA). Results 107 patients underwent RAPN in 4 participating Belgian centers from July 2024 until October 2025. In 56 cases, the surgery was performed TP, while in 51 cases a RP approach was used. The availability of a 3DPZ model did not differ across the different surgical approaches (χ2 p = 0.489). SC was performed in 73 (68%) cases and did not significantly differ between TP vs RP (χ2 p = 0.932). Also, planning and performing as planned a SC strategy (the primary endpoint of the PODRACING trial) did not significantly differ (χ2 p = 0.708). Median total operative time was significantly longer for TP (median 167 (IQR 140-210) min) than for RP (median 149 (IQR 113-186) min) (p = 0.024). Intraoperative and early postoperative complications were scarce in both groups. Conclusion SC can be equally performed in the TP or RP approach, both in terms of frequency and accuracy of planning. Also, the occurrence of intraoperative and early postoperative complications did not differ between surgical approaches. This reassures us to further proceed with the PODRACING trial, allowing both TP and RP approaches, as no approach-related differences affecting the primary endpoint or short-term safety outcomes were detected in this interim analysis.