(UroToday.com) The 2023 AUA annual meeting included an advanced kidney cancer session, featuring a presentation by Dr. Joseph Jacob discussing the first analysis of the safety and efficacy of UGN-101 in the treatment of ureteral tumors. Treating ureteral tumors presents unique challenges, including endoscopic ablation and issues with drug delivery to the ureter. Additionally, many of these patients have severe chronic kidney disease or may not tolerate abdominal procedures.
Previously, UGN-101 has been approved for the chemoablation of low-grade upper tract urothelial cancer involving the renal pelvis and calyces based on data from the OLYMPUS trial.1 Patients with ureteral tumors were excluded from the trial, thus little is known about the safety and efficacy of treating ureteral tumors with UGN-101. At the AUA 2023 annual meeting, Dr. Jacob and colleagues reported the first results of a cohort of patients with ureteral tumors treated with UGN-101.
This study was a retrospective review of patients treated with UGN-101 at 15 high volume centers. The main inclusion criteria were biopsy proven upper tract urothelial carcinoma prior to UGN-101 treatment. Patients received a goal of 6 weeks of induction placed in the renal pelvis, with maintenance therapy given at the discretion of the treatment center. Dr. Jacob highlighted several definitions used in this study:
- Complete response rate: no residual disease after induction determined by treating physician on follow-up ureteroscopy
- Partial response: decreased tumor burden
- Ureteral stenosis: hydronephrosis requiring intervention or that typically would require intervention
Subsequently, the goal was to compare outcomes of those with ureteral tumors with or without renal pelvis tumors and those with only renal pelvis tumors. Efficacy endpoints were evaluated via results at first endoscopic evaluation as well as rates of recurrence and progression. Adverse outcomes were characterized with a focus on the rate of ureteral stenosis.
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%). The baseline characteristics are summarized as follows:
As follows is the flow diagram for assessing response to therapy:
There was no difference in outcomes at first endoscopic evaluation between cases involving the ureter versus cases without ureteral involvement (p = 0.644):
The summary of results is as follows:
- Complete response rate in the ureter: 47.8%
- Partial response rate in the ureter: 26.1%
- Any response rate in the ureter: 73.9%
- Progression free survival at 12 months: 78%
- New onset of ureteral stenosis: 5.4%
- Overall incidence of ureteral stenosis: 37.8%
Dr. Jacob also highlighted the following limitations of this study:
- Heterogeneous group of patients from varying practices with various treatment approaches
- Almost all outcomes based on physician interpretation with no standardized or central review
- Very small sample size from large number of centers
Dr. Jacob concluded his presentation by discussing the first analysis of the safety and efficacy of UGN-101 in the treatment of ureteral tumors with the following take-home messages:
- UGN-101 appears to be equally safe and efficacious in treating low grade urothelial carcinoma of the ureter as compared to renal pelvic tumors
- This data warrants further study of the use of UGN-101 for the treatment of low grade urothelial carcinoma of the ureter
Presented by: Joseph Jacob, MD, MCR, SUNY Upstate University Medical Center, Syracuse, NY
Written by: Zachary Klaassen, MD, MSc – Urologic Oncologist, Assistant Professor of Urology, Georgia Cancer Center, Augusta University/Medical College of Georgia, @zklaassen_md on Twitter during the 2023 American Urological Association (AUA) Annual Meeting, Chicago, IL, April 27 – May 1, 2023
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