Immune Checkpoint Inhibitors in Urothelial Carcinoma (Literature Review)

Bladder cancer is globally considered as one of the most aggressive neoplasms. Traditionally, first-line therapy for metastatic urothelial carcinoma has remained unchanged over the past decades and has been based on combinations of cisplatin. Unfortunately, almost all patients eventually progress and die from bladder cancer, despite the initial response associated with cisplatin-based combinations. Immune checkpoint inhibitors are becoming an increasingly widely used therapeutic option in many solid tumors. In bladder cancer, a high level of programmed death-ligand is determined by rapidly progressive and aggressive tumors and unsatisfactory survival rates. Although checkpoint inhibitors are effective in metastatic urothelial bladder cancer, only a small proportion of treated patients receive a clear benefit, while a large number of patients experience significant side effects and toxicity without improving quality of life or surviving. None of the available biomarkers at this point was associated with response rates. There is evidence of an correlation between PD-L1 expression, the efficacy of immune checkpoint inhibitors, and treatment outcomes in patients with bladder cancer. A major paradigm shift in bladder cancer medicine has followed the FDA approval of avelumab, pembrolizumab, durvalumab, atezolizumab, and nivolumab for the treatment of patients with metastatic urothelial carcinoma previously treated with chemotherapy. Combining classical clinicopathological parameters with data obtained via information technology, together with genomic profiling, could be the future of personalized therapy for bladder cancer.

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