A Systematic Review and Meta-Analysis of the Role of Immune Checkpoint Inhibitors (ICI) as Adjuvant Treatment for Localized High-Risk Muscle-Invasive Urothelial Carcinoma (MIUC).

Abstract

Nivolumab, a PD-1 ICI has been recently approved for the adjuvant treatment of high-risk MIUC patients. However, conflicting data from another randomized controlled trial (RCT) with atezolizumab makes the benefit of this treatment uncertain. We performed a systematic review and study-level meta-analysis to evaluate the benefit in terms of disease-free survival (DFS) with ICI adjuvant treatment for patients with high-risk MIUC. Considering the Preferred Reporting Items for Systematic Review statement, a systematic search was performed in PUBMED/MEDLINE, Scopus and EMBASE up to October 30, 2021. The statistical analysis was performed by RevMan 5.4 software in intention-to-treat (ITT) population and in predetermined subgroups. Two RCTRCT, with a total of 1518 patients, met the inclusion criteria. Systemic immunotherapy was atezolizumab for 406 patients and nivolumab for 353 patients. In the ITT population there was a nonsignificant benefit with the systemic adjuvant immunotherapy (HR:0.79, 95% CI 0.62-1.00; z=2.00) but with high heterogeneity (I2=65%). Regarding the subgroups, there was no benefit in PD-L1 negative (HR:0.81, 95% CI 0.70-1.00; z=1.96, I2=0%) and in non-neoadjuvant chemotherapy (HR:0.95, 95% CI 0.78-1.15; z=0.56, I2=0%). Adjuvant treatment with ICI to patients with high-risk MIUC reveals a nonsignificant impact in DFS. The lack of clinical benefit was demonstrated in all subgroups. These data reinforce the need for a careful selection of patients before offering this approach in daily practice.