Robotic distal ureterectomy for high-risk distal ureteral urothelial carcinoma: a retrospective multicenter comparative analysis (ROBUUST 2.0 collaborative group)

Background: The role of kidney-sparing surgery in patients with high-risk upper urinary tract urothelial carcinoma is controversial. The present study aimed to assess oncological and functional outcomes of robot-assisted distal ureterectomy in patients with high-risk distal ureteral tumors. Methods: The ROBUUST 2.0 multicenter international (2015-2022) dataset was used for this retrospective cohort analysis. High-risk patients with distal ureteral tumors were divided based on type of surgery: robot-assisted distal ureterectomy or robot-assisted nephroureterectomy. A survival analysis was performed for local recurrence-free survival, distant metastasis-free survival, and overall survival. After adjusting for clinical features of the high-risk prognostic group, Cox proportional hazard model was plotted to evaluate significant predictors of time-to-event outcomes. Results: Overall, 477 patients were retrieved, of which 58 received robot-assisted distal ureterectomy and 419 robot-assisted nephroureterectomy, respectively, with a mean (±SD) follow-up of 29.6 months (±2.6). The two groups were comparable in terms of baseline features. At survival analysis, no significant difference was observed in terms of recurrence-free survival (P=0.6), metastasis-free survival (P=0.5) and overall survival (P=0.7) between robot-assisted distal ureterectomy and robot-assisted nephroureterectomy. At Cox regression analysis, type of surgery was never a significant predictor of worse oncological outcomes. At last follow-up patients undergoing robot-assisted distal ureterectomy had significantly better postoperative renal function. Conclusions: Comparable outcomes in terms of recurrence-free survival, metastasis-free survival, and overall survival between robot-assisted distal ureterectomy and robot-assisted nephroureterectomy patients, and better postoperative renal function preservation in the former group were observed. Kidney-sparing surgery should be considered as a potential option for selected patients with high-risk distal ureteral UTUC.