First analysis of the safety and efficacy of UGN-101 in the treatment of ureteral tumors

Objective: UGN-101 has been approved for the chemoablation of low-grade upper tract urothelial cancer (UTUC) involving the renal pelvis and calyces. Herein is the first reported cohort of patients with ureteral tumors treated with UGN-101. Patients and Methods: We performed a retrospective review of patients treated with UGN-101 for UTUC at 15 high-volume academic and community centers focusing on outcomes of patients treated for ureteral disease. Patients received UGN-101 with either adjuvant or chemo-ablative intent. Response rates are reported for patients receiving chemo-ablative intent. Adverse outcomes were characterized with a focus on the rate of ureteral stenosis. Results: In a cohort of 132 patients and 136 renal units, 47 cases had tumor involvement of the ureter, with 12 cases of ureteral tumor only (8.8%) and 35 cases of ureteral plus renal pelvic tumors (25.7%). Of the 23 patients with ureteral involvement who received UGN-101 induction with chemo-ablative intent, the complete response was 47.8%, which did not differ significantly from outcomes in patients without ureteral involvement. Fourteen patients (37.8%) with ureteral tumors had significant ureteral stenosis at first post-treatment evaluation, however, when excluding those with pre-existing hydronephrosis or ureteral stenosis, only 5.4% of patients developed new clinically significant stenosis. Conclusions: UGN-101 appears to be safe and may have similar efficacy in treating low-grade urothelial carcinoma of the ureter as compared to renal pelvic tumors.