Impact of On-Demand Selective Suturing on Renal Function Preservation During Clampless Robotic-Assisted Partial Nephrectomy: Insights from a Large Multicentric Italian Cohort

Objectives: To evaluate perioperative outcomes, renal function preservation, and short-term oncologic results of off-clamp, sutureless, or selectively sutured robotic-assisted partial nephrectomy (RAPN) in patients with renal tumors treated at multiple high-volume centers. Methods: This multicenter retrospective study included 250 patients who underwent off-clamp, sutureless/selectively sutured RAPN between January 2018 and December 2024. Patients with solitary kidneys, tumors > 7 cm, or prior renal surgery were excluded. All procedures were performed without renal artery clamping, using hemostatic agents and selective suturing when necessary. Perioperative, functional, and oncologic outcomes were compared with 313 patients who underwent standard RAPN with parenchymal suturing. Results: The median operative time was 110 min (IQR 100-140), and the median estimated blood loss was 180 mL (IQR 100-250). The overall complication rate was 8.4%, predominantly Clavien-Dindo grade I-II, with no conversions to open surgery. The median decline in estimated glomerular filtration rate (eGFR) at three months was 5.5% (IQR 3.5-8.9; p = 0.56), and no cases of acute kidney injury were recorded. The positive surgical margin rate was 3.7%, and no tumor recurrences were observed during the 12-month follow-up period. Conclusions: Off-clamp, sutureless or selectively sutured robotic-assisted partial nephrectomy (RAPN) was not associated with increased perioperative risk, renal functional decline, or compromised short-term oncologic control compared with conventional sutured RAPN. These findings indicate that the technique is feasible and safe in appropriately selected patients, although prospective studies with longer follow-up are needed to confirm long-term outcomes and refine patient selection criteria.