# Radiosurgery in Upper Tract Urothelial Carcinoma (UTUC)

## TL;DR

Radiosurgery offers a safe and effective treatment for kidney cancer patients who cannot undergo surgery, preserving kidney function and controlling the disease long-term.

## Contribution

This study demonstrates radiosurgery as a durable, non-surgical alternative for UTUC patients with promising long-term outcomes.

## Key findings

- Radiosurgery achieved a complete response in 82.2% of patients with UTUC.
- Median overall survival was 91.7 months, with no correlation to tumor grade or CIS.
- Only 6.7% of patients required hemodialysis, indicating preserved kidney function.

## Abstract

Upper tract urothelial carcinoma is an uncommon cancer often managed by removing the kidney and ureter. However, some patients cannot undergo major surgery or have just one working kidney, leaving them with few treatment options to avoid hemodialysis. This study examined whether a precise form of radiation therapy—mainly given in a single high-dose session—could safely control the disease while maintaining kidney function. Researchers reviewed long-term results from patients at specialist centers to evaluate survival rates, tumor response, and effects on kidney health. The results indicate that targeted radiation may offer lasting cancer control with manageable side effects, presenting a new possible alternative for those unable to have surgery and shaping future research into its place in routine care.

Objectives Radiosurgery (RS) using high-dose hypo-fractionated radiation is a novel treatment for renal cell carcinoma. This study investigates long-term oncological outcomes of RS for upper tract urothelial carcinoma (UTUC) in patients unfit for surgery or with a solitary kidney. Methods We performed a retrospective analysis of three prospective institutional databases from tertiary referral centers, including patients with UTUC treated with RS between 2008 and 2024. Results The study included 45 patients with a median age of 71.9 years (range 47.8–89.1). Of these, 28 had high-grade disease, and 9 carcinoma in situ (CIS). Twenty-eight patients had a solitary kidney. The median RS dose per fraction was 25 Gy (range 10–25). The median number of fractions was 1 (range 1–4 fractions). The median follow-up was 27.6 months (range 3.1–150.3), and the median overall survival (OS) was 91.7 months (95% CI 72.0–111.5). OS did not correlate with tumor grade or CIS. The median OS for low-grade patients was 52.06 months, while for high-grade patients, it was 87.90 months. Treatment response included complete response in 37 patients (82.2%), partial response in 2 (4.4%), stable disease in 2 (4.4%), and progression in 2 (4.4%). The median baseline and follow-up CKD-EPI were 64.2 and 53.5 mL/min/1.73 m2, respectively. Three patients (6.7%) required hemodialysis. Conclusions RS for UTUC is an effective local ablation therapy with durable long-term control and should be considered in patients not suitable for surgical approaches. It should be evaluated as a potential new standard of care in prospective studies in conjunction with peri-interventional systemic therapy.