[A comparative study on perioperative outcomes and learning curves of domestic robot-assisted versus Da Vinci Xi...

Objective: To compare perioperative outcomes of robot-assisted partial nephrectomy (RAPN) performed with a China-made robotic surgical system versus the Da Vinci Xi system, and to evaluate the learning curve of the domestic system. Methods: This single-center, prospective, randomized controlled study enrolled patients scheduled for RAPN at Harbin Medical University Cancer Hospital from August 2024 to May 2025 who met predefined inclusion and exclusion criteria. Using simple randomization, patients were assigned to the domestic robotic system group (domestic group) or the Da Vinci Xi group. Perioperative variables were analyzed and compared between groups using the independent-samples t test, Mann-Whitney U test, or Fisher's exact test, as appropriate. A cumulative sum (CUSUM) analysis of operative time in the domestic group was performed to determine the number of cases required for a surgeon to achieve proficiency when transitioning from the Da Vinci Xi to the SR2000 system. Results: Ninety patients undergoing robot-assisted laparoscopic RAPN were included and randomized (domestic group, n=45; Da Vinci Xi group, n=45). There were 56 males and 34 females,aged (M(IQR)) 57(48)years (range:31 to 79 years). TNM stages were T1N0M0 in 80 cases and T2N0M0 in 10 cases. All 90 procedures were successfully completed with robotic assistance, and no positive surgical margins occurred. Between-group differences in operative time, docking time, length of hospital stay, and intraoperative blood loss were not statistically significant (all P>0.05). The warm ischemia time of the domestic group was shorter than that of the Da Vinci Xi group(23 (10) min vs. 24 (8) min, Z=0.167, P<0.05). The CUSUM learning-curve fit for operative time in the domestic group showed an inflection at the 18th case, indicating that approximately 18 cases were required to complete the learning curve. When the domestic group was divided into a learning phase (cases 1 to 18) and a proficiency phase (cases 19 to 45), perioperative outcomes did not differ significantly between phases (all P>0.05). Conclusions: The domestic robotic surgical system can be used safely and effectively for partial nephrectomy. For surgeons already experienced with the Da Vinci Xi system, approximately 18 cases are required to attain proficiency with the SR2000 system.