Antibody Therapy in Treating Patients With Refractory or Relapsed Non-Hodgkin's Lymphoma or Chronic Lymphocytic Leukemia

DISEASE CHARACTERISTICS: * Diagnosis of CD19+ non-Hodgkin's lymphoma or chronic lymphocytic leukemia * Primary refractory or multiply relapsed (after at least 2 prior chemotherapy regimens) disease * Ineligible for bone marrow or peripheral blood stem cell transplantation PATIENT CHARACTERISTICS: Age: * Over 18 Performance status: * ECOG 0-2 Life expectancy: * More than 3 months Hematopoietic: * WBC greater than 3,000/mm\^3 * Platelet count greater than 100,000/mm\^3 * Absolute neutrophil count greater than 1,500/mm\^3 Hepatic: * Bilirubin less than 1.5 mg/dL * Alkaline phosphatase less than 2 times normal * SGPT less than 2 times normal Renal: * Creatinine clearance greater than 50 mL/min Other: * No human-anti-murine-antibody response to prior murine monoclonal antibodies * No immunological or inflammatory disease (e.g., lupus erythematosus) * No active serious infection * No other serious medical condition that would limit survival to less than 2 years * No other active malignancy except non-melanoma skin cancer or carcinoma in situ of the cervix * No psychiatric or addictive disorder that would preclude study * Not pregnant or nursing * Fertile patients must use effective contraception PRIOR CONCURRENT THERAPY: Biologic therapy: * Prior immunotherapy allowed Chemotherapy: * See Disease Characteristics * No concurrent chemotherapy Endocrine therapy: * Concurrent steroids for adrenal failure or adverse reactions to study drug allowed * Concurrent hormonal therapy for non-disease related conditions (e.g., insulin for diabetes) allowed Radiotherapy: * Not specified Surgery: * Not specified