OUTLINE: Patients are stratified according to prior treatment (yes vs no). Patients with prior treatment are further stratified according to type of treatment (alkylating agents vs purine nucleoside analogues). Patients receive rituximab IV over 4 hours on days 1, 8, 15, and 22. Patients are followed every 3 months for 2 years, every 6 months for 3 years, and then annually thereafter.