Nivolumab and RT in Treating Patients With Localized/Locally Advanced Urothelial Bladder Cancer Ineligible for Chemo

PRIMARY OBJECTIVES: I. To compare the 12-month rate of progression-free survival (PFS) achieved with the combination of nivolumab, a programmed death (PD-1) inhibitor, and radiation therapy in localized/locally advanced urothelial cancer patients, who are chemotherapy ineligible, to a historical control reference 12-month PFS rate. SECONDARY OBJECTIVES: I. To assess the toxicity of concurrent nivolumab and radiation therapy in urothelial cancer. II. To determine overall response rate (ORR). III. To determine metastasis-free survival (MFS). IV. To determine overall survival (OS). V. To evaluate the quality of life and bladder functioning during and after the therapy. VI. To explore the relationships of PD-1 expression, PDL-1 expression, and the Th1/Th2 cytokine ratio to clinical outcomes (response, PFS, MFS, and OS). OUTLINE: Patients receive nivolumab intravenously (IV) over 30 minutes on day 1. Treatment repeats every 14 days (2 weeks) for up to 14 courses (6 months) in the absence of disease progression or unacceptable toxicity. Beginning 3 days of course 1, patients undergo radiation therapy over 32-35 on weeks 1, 3, 5, 7 and 9. After completion of study treatment, patients are followed up every 3 months for 12 months.