CT urography and urinary cytology in surveillance of endoscopically managed UTUC

Our objective was to assess whether non-invasive surveillance with computed tomography (CT) urography and urinary cytology could safely reduce the need for ureteroscopy (URS) in patients with upper tract urothelial carcinoma treated with endoscopic kidney-sparing surgery (eKSS).

We performed a retrospective multicentre analysis of patients undergoing eKSS for upper tract urothelial carcinoma at two tertiary centres (2006-2025). Surveillance included second-look URS at 4-6 weeks, then every 6 months for 2 years and annually thereafter. CT urography and urinary cytology were performed within 3 months before each URS, and this served as the reference standard. Four trigger strategies were evaluated for diagnostic performance. Analysis started from the third URS. Recurrence over time was analysed using annualized rates per person-year, accounting for multiple recurrences and treating radical nephroureterectomy as a competing event, overall and by risk group.

A total of 133 patients and 256 ureteroscopic assessments were included. Combined CT and/or cytology showed sensitivity of 35.5%, specificity of 75.0%, a positive predictive value of 64.1% (95% confidence interval [CI] 52.4-74.7), and a negative predictive value of 48.0% (95% CI 40.4-55.7), avoiding 69.2% of URS (95% CI 63.1-74.8) but missing 64.5% of recurrences (95% CI 56.0-72.4). Cytology alone was highly specific (97%) but poorly sensitive (11%); CT alone showed moderate sensitivity (27%) and good specificity (78%); requiring both to be positive yielded near-perfect specificity but near-zero sensitivity (2.8%). Recurrence rates were stable across follow-up years at 0.34, 0.35, 0.35, and 0.28 events/person-year at years 1-4 in the low-risk group, and 0.33, 0.38, 0.32, and 0.32 in the high-risk group.

CT urography and urinary cytology may reduce the frequency of URS but cannot safely replace endoscopic surveillance because of the high rate of missed recurrences. Stable recurrence rates over time support the need for continued long-term endoscopic follow-up after eKSS.