Endoscopic Kidney-sparing Surgery for Upper Tract Urothelial Carcinoma: Long-term Oncological and Functional Outcomes from a Large Single-center Cohort.

BACKGROUND

Long-term benchmark data on endoscopic kidney-sparing surgery (eKSS) for upper tract urothelial carcinoma (UTUC) remain limited.

OBJECTIVE

To report long-term oncological and functional outcomes from a large single-center cohort using contemporary risk stratification.

DESIGN, SETTING, AND

PARTICIPANTS

We retrospectively analyzed a prospectively maintained cohort (August 1996-September 2024). After excluding patients with upfront radical nephroureterectomy (RNU) after diagnostic ureteroscopy, missing index pathology, or lacking oncologic follow-up, 254 eKSS-treated patients were included.

INTERVENTION: Endoscopic kidney-sparing surgery, with patients classified as low- (LR) or high-risk (HR) per EAU criteria and undergoing standardized surveillance including second-look ureteroscopy at 4-6 weeks and long-term ureteroscopic follow-up.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Outcomes included UTUC recurrence, RNU, metastases, cancer-specific mortality (CSM), and chronic kidney disease (CKD) ≥IIIB. Cumulative incidence functions and Fine-Gray competing-risk regression were used.

RESULTS AND LIMITATIONS: Median age was 71 years (IQR 62-77); 74% were male and 46% were LR. After a median follow-up of 67 months (IQR 24-131) for survivors, 5- and 7-yr recurrence incidence was 49% (95% CI 42-57%) and 55% (95% CI 47-63%), without statistically significant differences between risk groups (subdistribution hazard ratio [sHR] 0.74, 95% CI 0.51-1.08, p=0.12). High-risk disease was associated with higher hazards of RNU (sHR 2.30, 95% CI 1.34-3.94; 7-yr risk 35% vs. 13%), metastatic progression (7-yr incidence 17% vs. 5.0%; sHR 2.79, 95% CI 1.10-7.08), and CSM (7-yr incidence 23% vs. 11%, 95% CI 9.2-23%; sHR 2.24, 95% CI 1.10-4.55) compared to LR patients. Median eGFR decline was -9 mL/min/1.73 m2 (IQR -11 - -2); 5-yr CKD ≥IIIB incidence was 15% (95% CI 8-21%), with no risk-group statistically significant differences (sHR 1.63, 95% CI 0.72-3.70; p = 0.2).

CONCLUSIONS

These long-term data provide real-world benchmarks for clinicians counseling patients undergoing eKSS. High-risk disease is associated with higher hazards of RNU conversion, metastatic progression, and CSM, reinforcing the prognostic value of EAU risk stratification and the need for risk-adapted, prolonged endoscopic surveillance after eKSS.