Incidence of Low-risk Upper Tract Urothelial Carcinoma in Candidates for Kidney-sparing Surgery

Background/Aim: This study aimed to determine the incidence of low-risk upper tract urothelial carcinoma in candidates for kidney-sparing surgery based on the European Association of Urology risk stratification system by analyzing specimens obtained after radical nephroureterectomy. Patients and Methods: We retrospectively analyzed 118 patients who underwent radical nephroureterectomy without distant metastases or prior treatment between 2010-2022. Patients meeting all six factors of risk stratification were classified as having low-risk upper tract urothelial carcinoma. The incidence of low-risk patients was calculated. Additionally, the extravesical recurrence-free survival rate was assessed in these patients. Pathological data from radical nephroureterectomy specimens were used for conducting a detailed analysis of the aforementioned factors. Results: The pathological T stage was pT1 or lower in 58 patients (49%). Seven patients (6%) met all six factors for low-risk upper tract urothelial carcinoma, and low-risk patients had a pathological T stage of pT1 or lower. The 5-year extravesical recurrence-free survival rate for the overall cohort was 74.9%. Low-risk patients demonstrated a more favorable extravesical recurrence-free survival rate compared to non-low-risk patients (100% vs. 73.3% at 5 years, respectively). Among the six risk factors, "tumor size <20 mm" was the only significant predictor of extravesical recurrence in both univariate and multivariable analyses. Conclusion: Six percent of patients undergoing radical nephroureterectomy may be eligible for kidney-sparing surgery. Despite the limited number of identified patients, patients with low-risk upper tract urothelial carcinoma exhibited excellent outcomes. Kidney-sparing surgery may be a viable option in carefully selected patients.