Purpose

This phase III trial studies how well pembrolizumab works in treating patients with bladder cancer that has spread into the deep muscle of the bladder wall (muscle-invasive) or urothelial cancer that has spread from where it started to nearby tissue or lymph nodes (locally advanced). Monoclonal antibodies recognizing and blocking checkpoint molecules can enhance the patient's immune response and therefore help fight cancer. Pembrolizumab is one of the monoclonal antibodies that block the PD-1 axis and can interfere with the ability of tumor cells to grow.