A standard treatment for bladder cancer that has invaded into the muscle layer of the bladder is to first give chemotherapy medication for several months and then surgically remove the bladder. Surgical removal of the bladder is a major operation and is associated with a potential risks. Also, because the bladder is where urine is stored in the body, when the bladder is surgically removed, the urine has to exit the body differently. For many patients, this means that the urine will be drained into a bag outside of the body called a urostomy. When chemotherapy medication is given through a vein for several months prior to surgery to remove the bladder, sometimes there is no more cancer in the bladder specimen when it is taken out of the body and inspected in the laboratory. If we could identify which patients might have their bladder cancer eliminated with chemotherapy medication alone, this could mean that some patients may be cured without having their bladder removed. We are testing whether given chemotherapy together with immunotherapy, medication to enhance the body’s immune system to fight cancer, is better at completely eliminating cancer in the bladder and also testing whether we can identify patients that are the best candidates for this approach by studying several features of an individual patient’s cancer before and after treatment. If our work is successful, we hope to be able to select patients who can have their bladder cancer cured with the combination of chemotherapy and immunotherapy without requiring surgical removal of their bladder.