Perioperative outcomes of open versus robot-assisted radical nephrectomy with IVC thrombectomy.

468 Background: Renal cell carcinoma (RCC) with inferior vena cava (IVC) tumor thrombus presents complex surgical challenges and significant perioperative morbidity. Traditionally managed with open radical nephrectomy and IVC thrombectomy, robotic-assisted approaches have emerged as a promising alternative. Due to the rarity of these procedures and the novelty of robotic techniques, comparative data are limited, often derived from small cohorts. This study compares perioperative outcomes of open versus robotic radical nephrectomy with IVC thrombectomy for level II-III thrombi using a large, multi-institutional database. Methods: We analyzed patients undergoing radical nephrectomy with IVC thrombectomy for AJCC T3b RCC from 2019 to 2023, identified through the ACS-NSQIP database using relevant CPT codes and pathologic staging. Patients were stratified by surgical approach (open vs. robotic). Baseline demographics, comorbidities, and 30-day perioperative outcomes were compared using chi-square tests and Student’s t-tests. Primary outcomes included major and minor complications, operative time, hospital length of stay (LOS), readmission, and mortality rates. Results: Of 321 patients, 256 (79.8%) underwent open and 65 (20.2%) underwent robotic IVC thrombectomy. Both groups were comparable in age, sex, BMI, and comorbidities, though robotic patients had lower ASA scores (p<0.0001). Robotic surgery was associated with significantly lower minor complication rates (33.8% vs. 64.7%, p<0.001), driven by reduced bleeding complications (30.8% vs. 56.3%, p=0.002). Hospital LOS was shorter in the robotic group (3.9 ± 3.8 vs. 7.5 ± 5.0 days, p<0.001). No significant differences were observed in 30-day major complication rates (10.8% vs. 21.1%, p=0.058), reoperation (3.1% vs. 1.6%, p=0.42), readmission (6.2% vs. 10.9%, p=0.25), or mortality rates (3.1% vs. 2.0%, p=0.58). Conclusions: This study, the largest to date, demonstrates that both open and robotic IVC thrombectomy for RCC with level II-III thrombi carry substantial perioperative morbidity. There was no difference in 30-day rates of major complications or mortality. Robotic surgery offered reduced blood loss and a shorter hospital stay, findings that have been demonstrated across various robotic operations. These findings suggest robotic IVC thrombectomy represents a viable alternative to open surgery in appropriately selected patients at experienced centers, without compromising perioperative safety outcomes. Open vs robotic IVC thrombectomy patient outcomes. Open N = 256 RoboticN = 65 P-value Minor Complications 167 (64.73%) 22 (33.85%) <0.0001* Major Complications 54 (21.09%) 7 (10.77%) 0.0581 Length of Total Hospital Stay (days) 7.53 ± 5.04 3.91 ± 3.79 <0.0001* Return to operating room 4 (1.56%) 2 (3.08%) 0.4208 Readmission 28 (10.94%) 4 (6.15%) 0.2503 Death 5 (1.95%) 2 (3.08%) 0.5796 *Statistically significant.