Outcome of patients with advanced upper tract urothelial carcinoma treated with immune checkpoint inhibitors: A systematic review and meta-analysis

Background Advanced upper tract urothelial carcinoma (UTUC) has different molecular and genetic features from the commonest carcinoma of the bladder, suggesting a possible different sensitivity to immune-checkpoint inhibitors (ICI). Methods A systematic review and meta-analysis of all relevant clinical studies including advanced UTUC patients treated with ICI was conducted according to PRISMA guidelines. Results Six prospective trials for a total 2537 patients, including 396 (15.6 %) with advanced UTUC, were eligible for the analysis. In UTUC patients, the pooled ORR was 21.2 % (95 % CI, 12.5 %–33.7 %); the risk of death was reduced by 24 % over the standard platinum-based chemotherapy, but this was not statistically significant (hazard ratio = 0.76; 95 % confidence interval, 0.41–1.40; p = 0.37, χ2 = 3.28, p = 0.07; I2 = 70 %). Conclusions The current evidence does not support a statistically significant effect from ICI over the standard treatment for advanced UTUC patients. Properly performed pre-planned subgroup analyses from randomized clinical trials are eagerly awaited.