The aim of our study is to evaluate the effectiveness and safety of a sutureless off-clamp robot-assisted partial nephrectomy (sl-oc RAPN), particularly its impact on renal function. A multicenter study was conducted from April 2021 to June 2022. Patients diagnosed with a renal mass of >2 cm and a PADUA score of ≤6 consecutively underwent an sl-oc RAPN procedure. Tumor features, patients characteristics, and intraoperative outcomes were assessed. An evaluation of renal function was performed preoperatively, and again at 1 and 3 months after surgery by measuring the creatinine and blood urea nitrogen levels. The renal function of the two separate kidneys was assessed by a sequential renal scintigraphy performed before and at least 30 days after surgery. A total of 21 patients underwent an sl-oc RAPN. The median age was 64 years (IQR 52/70), the median tumor diameter was 40 mm (IQR 29/45), and the median PADUA score was 4 (3.5/5). The intraoperative outcomes included operative time (OT), 90 (IQR 74/100) min; estimated blood loss (EBL), 150 (IQR 50/300) mL; and perioperative complications, CD > 3 1(5%); only two patients presented positive surgical margins in their final histology (2/21, 10%). Compared to the preoperative value, a decrease in renal function was highlighted with a statistically significant median decrease of 10 mL/min (p < 0.01). The renal scintigraphy showed an overall decrease in renal function compared to the preoperative value, with a range in the operated kidney that varied from 0 to 15 mL/s and from 0% to 40%, with a median value of 4 mL/s and 12%. sl-oc RAPN is a safe procedure, with a minimal impact on kidney function alteration. This technique has proven effective in preserving renal function and maintaining optimal oncological outcomes with limited complications.
