OBJECTIVES: I. Determine the response rate and disease free survival of HIV seronegative patients with diffuse small noncleaved cell lymphoma or L3 acute lymphocytic leukemia when treated with high intensity, brief duration combination chemotherapy: alternating courses of ifosfamide/cytarabine/etoposide and cyclophosphamide/doxorubicin, each with methotrexate/vincristine/dexamethasone. II. Determine the toxicity of these regimens in HIV negative patients.