OUTLINE: This is a randomized, open label, parallel, multicenter study. Patients are stratified according to complete remission (first vs subsequent). Patients are randomized to one of two treatment arms. Arm I: Following consolidation chemotherapy or autologous stem cell transplantation, patients receive interleukin-2 subcutaneously followed by histamine dihydrochloride subcutaneously over 5-7 minutes twice daily on days 1-21. Treatment repeats every 6 weeks for 3 courses and then every 9 weeks for 7 courses in the absence of disease relapse or unacceptable toxicity. Arm II: Patients receive no further therapy following consolidation chemotherapy or autologous stem cell transplantation. Quality of life is assessed prior to study, and at visits 6, 7, 10, 11, 16, 17, and 22. Patients are followed for relapse and survival every 3 months for 2.5 years.