The Impact of Primary Tumor Location on Long-Term Oncological Outcomes in Patients with Upper Tract Urothelial Carcinoma Treated with Radical Nephroureterectomy: A Systematic Review and Meta-Analysis

Background: Upper tract urothelial carcinoma (UTUC) accounts for up to 10% of all urothelial neoplasms. Currently, various tumor-related factors are proposed to be of importance in UTUC prognostic models; however, the association of the primary UTUC location with oncological outcomes remains controversial. Thus, we sought to perform a systematic review and meta-analysis of the latest available evidence and assess the impact of primary tumor location on long-term oncological outcomes in patients with UTUC undergoing radical nephroureterectomy. Materials and Methods: A computerized systematic literature search was conducted in October 2021 through the PubMed, Web of Science, Scopus, and Cochrane Library databases. The primary endpoint was cancer-specific survival (CSS), and the secondary endpoints were overall survival (OS) and disease-free survival (DFS). Effect measures for the analyzed outcomes were reported hazard ratios (HRs) and 95% confidence intervals (CIs). Results: Among the total number of 16,836 UTUC in 17 included studies, 10,537 (62.6%) were renal pelvic tumors (RPTs), and 6299 (37.4%) were ureteral tumors (UTs). Pooled results indicated that patients with UT had significantly worse CSS (HR: 1.37, p < 0.001), OS (HR: 1.26, p = 0.003, and DFS (HR: 1.51, p < 0.001) compared to patients with RPT. Based on performed subgroup analyses, we identified different definitions of primary tumor location and geographical region as potential sources of heterogeneity. Conclusions: Ureteral location of UTUC is associated with significantly worse long-term oncological outcomes. Our results support the need for close follow-up and the consideration of perioperative chemotherapy in patients with UTUC located in the ureter. However, further prospective studies are needed to draw final conclusions.