OUTLINE: This is a randomized, open label, controlled, multicenter study. Patients are randomized into one of two arms for induction chemotherapy. Arm I: Patients receive oral chlorambucil three times daily for 3 consecutive days, oral idarubicin daily for 3 consecutive days, and oral dexamethasone twice daily for 5 consecutive days every 21 days. Arm II: Patients receive oral chlorambucil three times daily for 3 consecutive days and oral dexamethasone twice daily for 5 consecutive days every 21 days. Treatment for both arms continues for up to 6 courses in the absence of disease progression or unacceptable toxicity. After 6 courses of chemotherapy, patients are reassessed. If they have achieved maximal complete response or good partial response, patients are randomized into one of three arms. Arm I: Patients receive no further treatment until disease progresses. Arm II: Patients receive low dose interferon alfa subcutaneously three times per week for a maximum of 3 years in the absence of disease progression. Arm III: Patients receive standard dose interferon alfa subcutaneously three times a week for a maximum of 3 years in the absence of disease progression. Patients are followed every 8-12 weeks for 3 years.