Transperitoneal versus retroperitoneal single-port robot-assisted partial nephrectomy: systematic review and...

To systematically compare the safety and efficacy of the transperitoneal (TP) and retroperitoneal (RP) approaches in single-port robot-assisted partial nephrectomy (SP-RAPN). PubMed, Web of Science, and Embase were searched for comparative studies published before October 2025. The primary evaluated outcomes were grouped as Perioperative Outcomes (operative time, blood loss, ischemia time, positive surgical margin, postoperative eGFR, and hospital stay) and Surgical Safety (complication rate). Study inclusion and exclusion standards followed the PICOS guidelines. Four comparative studies with 384 patients (188 TP and 196 RP) were analyzed. Compared with the RP group, the TP group had higher intraoperative blood loss (WMD = 27.95 mL, 95% CI = 4.90-51.02, p = 0.018), longer hospital stay (WMD = 0.56 days, 95% CI = 0.34-0.78, p < 0.001), and higher absolute postoperative eGFR (WMD = 6.87, 95% CI = 2.65-11.10, p = 0.001). Operative time did not differ significantly in the main analysis (p = 0.356); an exploratory sensitivity analysis suggested a possible small difference (≈ 12 min) that requires confirmation. Warm ischemia time, positive surgical margin rate, and complication rate showed no significant differences between the two groups. Sensitivity analysis confirms the robustness of these findings, with overall low heterogeneity. Both transperitoneal and retroperitoneal SP RAPN are safe and feasible based on this limited evidence. Preliminary findings suggest the RP approach may offer advantages in blood loss, hospital stay, and renal preservation, but these results are hypothesis generating. Importantly, tumor location strongly influenced approach selection, and observed differences may be attributable to tumor location rather than the approach itself; causal inference is not possible from this observational data. Validation in larger, prospective, and preferably randomized studies is required.