An Extracorporeal Photopheresis (ECP) is a therapeutic procedure that is used to treat advanced cutaneous T-cell lymphoma (CTCL), graft versus host disease (GVHD), solid organ transplant rejection, scleroderma, lupus, Crohn’s disease and Type 1 diabetes. This procedure may also help in the treatment of psoriasis, rheumatoid arthritis, multiple sclerosis, fibrosis and scleromyxedema. A patient’s blood is drawn and white blood cells are separated before being returned to the body. The white blood cells are mixed with psoralen, making them sensitive to UV light. The UV light kills the diseased cells and the treated WBCs are returned to the patient. This is a two-day process, but patients are not required to stay overnight. Side effects are minimal but they may include a low-grade fever, nausea and bruising around the injection site. Your doctor will discuss possible symptoms to look out for before the procedure.