OUTLINE: Patients enter one of two treatment arms: Arm I: Patients receive rituximab IV on days 1, 8, 15, and 22 for course 1, and then once a month for 11 months or until disease progression. Arm II: Patients receive subcutaneous interferon alfa-2b every other day three times per week for 12 months. Quality of life is assessed monthly during therapy. Patients are followed every 3 months for 1 year, and then annually for up to 5 years.