If you are found to be eligible, you will receive denileukin diftitox as an injection by vein once a day for 5 days in a row. This will be repeated every 3 weeks (1 cycle). You will receive treatment on an outpatient basis. Treatment will continue as long as there is evidence that therapy is affecting the disease and is beneficial to you. If the disease gets worse or you experience any intolerable side effects, you will be taken off the study and your doctor will discuss other treatment options with you.