Comparison of the efficacy and safety of metallic ureteral stent versus polymer ureteral stent for patients with malignant ureteral obstruction: a meta-analysis of comparative trials.

PURPOSE: This study aimed to evaluate and compare the clinical performance of metallic and polymer ureteral stents in patients with malignant ureteral obstruction (MUO), with a focus on complications and success rates. METHODS: We conducted a meta-analysis of seven studies, obtained by searching various databases from inception to February 2025, involving patients with MUO treated with metallic or polymer stents. Study quality was assessed using the RoB 2 tool for randomized controlled trials and the ROBINS-I tool for non-randomized studies. Primary outcomes included success rates at 1, 3, 6, and 12 months, and complication rates. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using a random-effects model. When data were available, exploratory analyses were performed according to metallic stent type. RESULTS: The success rates at 3, 6, and 12 months were consistently higher in patients with metal stents (ORs 5.14, 2.70, and 3.67, respectively) than in those with polymer stents. The overall rate of complications did not differ significantly between the two groups; however, a higher risk of complications was observed in studies using covered metallic stents (OR 4.45, 95% CI 1.57–12.62). CONCLUSIONS: Compared with polymer ureteral stents, metallic ureteral stents demonstrated higher success rates in patients with MUO, particularly at longer follow-up, albeit with an increased risk of complications. These findings suggest that metallic stents may represent a favorable option in carefully selected patients.