Abstract IA11: Chemotherapy remodels the bladder cancer immune microenvironment

Abstract

Abstract In the United States urothelial carcinoma (UC) of the bladder is the 4th and 9th most frequent malignancy in men and women, respectively, with around 74,000 new cases and 16,000 deaths in 2017. High-grade (HG), muscle-invasive bladder tumors account for the majority of those deaths as patients with metastatic disease have a 5-year survival rate of only 15%. The current standard-of-care first-line therapy for metastatic disease is cisplatin-based combination chemotherapy or immune checkpoint inhibition in patients who are platinum ineligible. Novel immune checkpoint (IC) inhibitors, including anti-PD1 and anti-PD-L1, represent a paradigm shift in cancer therapy and have demonstrated substantial clinical benefits in patients with advanced UC. Despite the enthusiasm engendered by PD-1/PD-L1 axis blockade in metastatic UC, only 15-25% of patients treated in published trials had objective responses. Preliminary studies from our laboratory show that chemotherapy remodels the immune microenvironment of muscle-invasive bladder cancers. We have begun to investigate the mechanisms by which chemotherapy drives a heightened immune response using our recently described genetically engineered murine (GEM) models of bladder cancer. Citation Format: William Y. Kim. Chemotherapy remodels the bladder cancer immune microenvironment [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2019 May 18-21; Denver, CO. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(15_Suppl):Abstract nr IA11.