Oncologic Outcomes of Patients Undergoing Diagnostic Ureteroscopy Before Radical Nephroureterectomy for Upper Urinary Tract Urothelial Carcinomas: A Systematic Review and Meta-Analysis

Background: Owing to the aggressive nature of radical nephroureterectomy (RNU), it is extremely important for the diagnostic modalities to be accurate. The European Association of Urology guidelines recommend that diagnostic ureteroscopy (URS) and biopsy be performed for upper urinary tract urothelial carcinomas (UUTCs). But that diagnostic URS adversely affects oncologic outcomes still exist. In the current systematic review and meta-analysis, we had attempted to evaluate oncologic outcome of diagnostic URS before RNU. Methods: All relevant articles were retrieved from PubMed, Embase, Web of Science, and the Cochrane Library. Endpoint events were recurrence-free survival, metastasis-free survival, cancer-specific survival, and overall survival. Results: Compared with patients who underwent RNU alone, those who underwent diagnostic URS before RNU had significantly higher intravesical recurrence rate (HR=1.42, 95% CI: 1.24-1.61, I-2=37%). Overall, no significant difference was found in CSS (HR=0.72, 95% CI: 0.51-1.03, I-2=0%) and OS (HR=0.73, 95% CI: 0.45-1.19, I-2=0%) between patients who underwent diagnostic URS and those who did not. Meanwhile, there was lack of evidence indicating that the risk of tumor metastasis increased after diagnostic URS (HR=0.97, 95% CI: 0.74-1.26, I-2=0%). Conclusions: Diagnostic URS before RNU does not seem to compromise long-term survival outcomes, even though it is associated with a higher rate of intravesical recurrence (IVR). Our findings suggest that further investigation, especially through prospective studies, should focus on decreasing the rate of IVR by administration of intravesical chemotherapy immediately after diagnostic URS.