Inclusion Criteria

DISEASE CHARACTERISTICS: Diagnosis of intermediate grade B-cell CD20+ non-Hodgkin's
lymphoma Failed to achieve initial complete response (CR) after at least 2 courses of
standard chemotherapy OR Relapsed after CR and not eligible for autologous bone marrow
transplant Measurable disease defined as one of the following: Bidimensionally measurable
disease at least 2 cm in diameter by radiograph or CT scan Enlarged spleen extending at
least 2 cm below the costal due to lymphomatous involvement Enlarged liver with focal
lesions on CT scan or biopsy proven lesions Lymphomatous hepatic involvement must be
biopsy proven for the liver to be sole area of measurable disease No evidence of CNS
involvement 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: 18 and over Performance status: ECOG 0-3 Life expectancy:
Not specified Hematopoietic: Absolute neutrophil count at least 1,500/mm3* Platelet count
at least 100,000/mm3* *unless there is bone marrow involvement with lymphoma Hepatic:
Bilirubin less than 3 mg/dL AST/ALT less than 2 times normal Renal: Creatinine less than
2.1 mg/dL OR Creatinine clearance greater than 60 mL/min Cardiovascular: LVEF greater than
45% by MUGA or echocardiogram Other: No prior malignancy within the past 10 years except
squamous cell carcinoma or basal cell carcinoma of the skin or cervical cancer No evidence
of infection HIV negative Not pregnant or nursing Negative pregnancy test Fertile patients
must use effective contraception

PRIOR CONCURRENT THERAPY: See Disease Characteristics No prior rituximab