DISEASE CHARACTERISTICS: Histologically proven intermediate or high grade B-cell non-Hodgkin's lymphoma (other than Burkitt's, non-Burkitt's, undifferentiated, or lymphoblastic lymphoma) B-cell non-Hodgkin's lymphoma positive for CD19 and/or CD20 by slide-based immunohistochemistry or flow cytometry No mantle cell or follicular lymphoma Measurable disease, defined by at least one of the following: Physical examination Radiographic findings of at least 2 dimensions Bidimensional measurable defect or mass measuring at least 2 cm in diameter on radionuclide or CT scan Enlarged spleen extending at least 2 cm below the costal margin provided that there is no other likely explanation besides lymphomatous involvement Enlarged liver extending at least 5 cm below the costal margin along with biopsy-proven lymphomatous hepatic involvement No history of transformed lymphoma No known posttransplantation lymphoproliferative disorder No CNS involvement CALGB patients 60-65 years of age must not be eligible for any other study of higher priority A new classification scheme for adult non-Hodgkin's lymphoma has been adopted by PDQ. The terminology of "indolent" or "aggressive" lymphoma will replace the former terminology of "low", "intermediate", or "high" grade lymphoma. However, this protocol uses the former terminology.

PATIENT CHARACTERISTICS: Age: See Disease Characteristics 60 and over Performance status: ECOG 0-3 Life expectancy: Not specified Hematopoietic: Absolute granulocyte count at least 1,500/mm3 (unless due to lymphoma) Platelet count greater than 100,000/mm3 (unless due to lymphoma) Hepatic: Bilirubin no greater than 3.0 mg/dL Renal: Creatinine less than 2.1 mg/dL OR Creatinine clearance at least 60 mL/min Cardiovascular: No active heart disease including congestive heart failure, myocardial infarction within the past 3 months, or symptomatic ventricular arrhythmia LVEF at least 45% if prior history of heart disease exists Other: HIV negative No other malignancy within the past 5 years except squamous cell or basal cell skin cancer or carcinoma in situ of the cervix

PRIOR CONCURRENT THERAPY: Biologic therapy: See Disease Characteristics No prior biologic response modifier therapy No prior immunotherapy No prior rituximab Chemotherapy: No prior cytotoxic chemotherapy No concurrent dexrazoxane Endocrine therapy: Prior corticosteroids allowed Radiotherapy: No prior radiotherapy No prior radioimmunotherapy Surgery: Not specified