Biopsy with Ureterorenoscopy Before Radical Nephroureterectomy is Associated with Increased Intravesical Recurrence in Urothelial Cancer Located in the Kidney.

OBJECTIVE: Diagnostic ureterorenoscopy is used to identify upper tract urothelial cancer before radical nephro ureterectomy, especially for uncertain lesions in imaging modalities or urine cytology. However, diagnostic ureterorenoscopy can potentially cause intravesical tumor spillage and can increase intravesical recurrence rates. We aimed to investigate the impact of diagnostic ureterorenoscopy before radical nephroureterectomy, with and without biopsy, on intravesical recurrence rates of patients with upper tract urothelial cancer. MATERIAL AND METHODS: Patients with localized upper tract urothelial cancer from 8 different tertiary referral centers, who underwent radical nephroureterectomy between 2001 and 2020, were included. Three groups were made: no URS (group 1); diagnostic ureterorenoscopy without biopsy (group 2); and diagnostic ure terorenoscopy with biopsy (group 3). Intravesical recurrence rates and survival outcomes were compared. Univariate and multivariate Cox regression analyses were performed to determine the factors that were asso ciated with intravesical recurrence-free survival. RESULTS: Twenty-two (20.8%), 10 (24.4%), and 23 (39%) patients experienced intravesical recurrence in groups 1, 2, and 3, respectively (P=.037) among 206 patients. The 2-year intravesical recurrence-free sur vival rate was 83.1%, 82.4%, and 69.2%, for groups 1, 2, and 3, respectively (P=.004). Cancer-specific survival and overall survival were comparable (P=.560 and P=.803, respectively). Diagnostic ureterore noscopy+biopsy (hazard ratio: 6.88, 95% CI: 2.41-19.65, P < .001) was the only independent predictor of intravesical recurrence in patients with upper tract urothelial cancer located in the kidney, according to tumor location. CONCLUSION: Diagnostic ureterorenoscopy+biopsy before radical nephroureterectomy significantly increased the rates of intravesical recurrence in tumors located in kidney. This result suggests tumor spillage with this type of biopsy, so further studies with different biopsy options or without biopsy can be designed.