 Patients will be treated with 9 mcgkgd of Denileukin diftitox intravenously for 5 days every 2 weeks. Tumor response will be evaluated after two cycles of treatment. Stable or responding patients will continue treatment for a total of 12 months, with evaluations every four cycles of treatment. Patients will be treated for two cycles beyond a complete remission. The trial uses an optimal two-stage design targeting for a true response proportion of more than 30 percent. Nine patients will be treated initially, with expansion to 29 patients if a response is seen in 1 of the initial 9 patients treated. Treatment will be discontinued if a patient experiences serious side effects. 