Rosen GH, Nallani A, Muzzey C et al: Antegrade instillation of UGN-101 (mitomycin for pyelocalyceal solution) for low-grade upper tract urothelial carcinoma: initial clinical experience. J Urol 2022; 207: 1302.

Study Need and Importance

Low-risk upper tract urothelial carcinoma is treated with endoscopic methods or radical nephroureterectomy. Endoscopic methods infer a high risk of recurrence. UGN-101 is a reverse hydrogel containing mitomycin that was recently released, and early results are promising that it should decrease this risk. Prior reports using this technology describe a retrograde approach using weekly cystoscopy with fluoroscopy, which can be cumbersome and expensive. There is also a significant risk of ureteral stricture. We describe our first experiences using an antegrade approach via nephrostomy.

What We Found

Figure 1. A, timeline for induction UGN-101 (mitomycin for peyelocalyceal solution) via antegrade approach for patients with low-risk upper tract urothelial carcinoma. B, potential advantages and disadvantages of antegrade approach for administration of UGN-101.

We detail our method for antegrade instillation of UGN-101 (Fig. 1, part A) and present the early outcomes from our first 8 patients (Fig. 2). There was complete response in 4 patients at first post-instillation ureteroscopy. Three patients reported 5 adverse events—3 grade 1, 1 grade 2 requiring 1-week delay of treatment and 1 asymptomatic ureteral stricture. Median followup was 7 months.

Limitations

This work is limited by small sample size and short followup. Larger studies with longer followup are needed to study more conclusively any potential advantages of antegrade UGN-101 administration when compared to retrograde instillation. Despite these limitations, we offer an easily replicable protocol for antegrade administration of UGN-101.

Figure 2. Visual abstract of study.

Interpretation for Patient Care

We discuss our technique and initial experiences with antegrade administration of UGN-101 (mitomycin for pyelocalyceal solution). There are potential advantages (Fig. 1, part B) to this approach, including greater patient comfort, more straightforward logistics and the potential for decreased risk of ureteral stricture. We hope that our description aids urologists in reproducing similar methods while we work together to form a larger, longer-term experience.