The Systematic Review of the Efficacy and Safety of Immune Checkpoint Inhibitor in Urological Cancers

ABSTRACT

To systematically review relevant literature on efficacy and safety of immune checkpoint inhibitors (ICIs) in patients with advanced and metastatic urothelial cell cancer (UCC), renal cell cancer (RCC), and prostate cancer. In platinum pretreated UCC, efficacy of pembrolizumab was superior to chemotherapy, with longer median overall survival (OS; 10.3 months vs. 7.4 months), a higher objective response rate (ORR; 21.1% vs. 11.4%, p=0.001), and a lower adverse event rate (60.9% vs. 90.2%). Three randomized controlled trials (RCTs) assessed the safety and efficacy of nivolumab in advanced RCC. The median OS (25.0 months vs. 19.6 months) and the ORR (25% vs. 5%) were higher in patients treated with nivolumab compared with second-line everolimus. In patients with metastatic castration-resistant prostate cancer, 2 RCTs were identified, which did not show significant benefits for ipilimumab over placebo. In UCC and RCC, there was no conclusive association between programmed cell death receptor ligand 1 (PD-L1) expression in tumor tissue and clinical outcome during pembrolizumab and nivolumab treatment, respectively. Therefore, in metastatic UCC and RCC, pembrolizumab and nivolumab have superior efficacy and safety to second-line chemotherapy and everolimus, respectively. No beneficial effect of ipilimumab was observed in prostate cancer patients. PD-L1 expression status is currently not suitable as a predictive marker for treatment outcome.