Malignant Renal Pelvis Neoplasm

This phase II trial tests how well enfortumab vedotin (EV) and pembrolizumab works in treating patients with bladder cancer of variant histology (a group of less common types of bladder cancer) that have spread to nearby tissue or lymph nodes (locally advanced) or that has spread from where it first started (primary site) to other places in the body (metastatic). Enfortumab vedotin is a monoclonal antibody, enfortumab, linked to an anticancer drug called vedotin. Enfortumab attaches to a protein called nectin-4 on cancer cells in a targeted way and delivers vedotin to kill them. It is a type of antibody-drug conjugate. Immunotherapy with monoclonal antibodies, such as pembrolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. Giving enfortumab vedotin and pembrolizumab may kill more tumor cells in patients with locally advanced or metastatic bladder cancer of variant histology.