Immune checkpoint inhibitor therapy as a neoadjuvant treatment for muscle-invasive bladder carcinoma

Abstract

Abstract Background and objectives Immunotherapy has become a standard treatment for patients with advanced urothelial carcinoma, and neoadjuvant immunotherapy is being extensively explored. This review highlights the initial findings and key clinical therapeutic insights on immune checkpoint inhibitors in the early treatment of muscle-invasive bladder cancer across diverse patient populations. Materials and methods Relevant trials were retrieved from PubMed/MEDLINE and clinical trials databases. In addition, abstracts of major international oncology meetings (American Society of Clinical Oncology, American Association for Cancer Research, European Society of Medical Oncology, and European Council of Clinical Oncology) were reviewed until the European Society of Medical Oncology 2023 congress. The review also incorporated results from several exploratory investigations disclosed in recent years. Results This review focused on neoadjuvant immune checkpoint inhibitor monotherapy, combination therapy, and clinical biomarkers in relation to cisplatin-based chemotherapy tolerance. Most available literature consists of clinical investigations involving small sample, single-arm Phase II trials, with the primary endpoint being the pathologic complete response rate. The preliminary results from these studies are promising, demonstrating stage reduction rates comparable to or even exceeding those of standard chemotherapy, without compromising subsequent radical cystectomy. Conclusions Early results of immune checkpoint inhibitors in the neoadjuvant treatment of bladder cancer have demonstrated promising efficacy. However, these findings require confirmation in large Phase III clinical trials, with particular emphasis on long-term survival benefits and identifying patients who respond to treatment.