Stage II Mycosis Fungoides and Sezary Syndrome AJCC v8

This phase II trial studies the effect of extracorporeal photopheresis (ECP) and mogamulizumab in treating patients with erythrodermic cutaneous T cell lymphoma (CTCL), a type of skin lymphoma. CTCL is a rare type of cancer that begins in the white blood cells called T cells. Erythrodermic is a widespread red rash that may cover most of the body. ECP is a medical treatment that removes blood with a machine, isolates white blood cells and exposes them to ultra violet light, then returns the cells to the body. Mogamulizumab is a monoclonal antibody that may interfere with the ability of cancer cells to grow and spread. Giving mogamulizumab with ECP may work together to kill the tumor cells directly (with mogamulizumab) and boost immune response to cancer (with ECP).