Inclusion Criteria

DISEASE CHARACTERISTICS:

- Diagnosis of Waldenstrom's macroglobulinemia

- CD20 positive by bone marrow immunohistochemistry or flow cytometry

- Presence of monoclonal paraprotein

- IgM level at least 2 times upper limit of normal (ULN)

PATIENT CHARACTERISTICS:

Age:

- Over 18

Performance status:

- ECOG 0-2

Life expectancy:

- At least 6 months

Hematopoietic:

- Absolute neutrophil count greater than 1,000/mm^3

- Platelet count greater than 25,000/mm^3

Hepatic:

- Bilirubin less than 2.5 times ULN

- SGOT less than 2.5 times ULN

Renal:

- Creatinine less than 2.5 mg/dL

Other:

- Not pregnant or nursing

- Fertile patients must use effective contraception during and for 6 months after study

- No serious comorbid disease

- No uncontrolled bacterial, fungal, or viral infection

- No other active malignancy

PRIOR CONCURRENT THERAPY:

Biologic therapy:

- No prior rituximab

- No prior nucleoside analogue therapy

Chemotherapy:

- At least 30 days since prior chemotherapy

Endocrine therapy:

- At least 30 days since prior steroid therapy

- No concurrent corticosteroids

Radiotherapy:

- At least 30 days since prior radiotherapy

Surgery:

- Not specified

Other:

- No more than 2 prior courses of therapy