Combination Chemotherapy and Rituximab in Treating Patients With Newly Diagnosed Burkitt's Lymphoma or Leukemia

OBJECTIVES: Primary * Determine the overall response rate, 1-year event-free survival, and overall survival of adult patients with newly diagnosed Burkitt or atypical Burkitt lymphoma or leukemia treated with dose-intensified induction therapy comprising cyclophosphamide, vincristine, prednisone, and rituximab followed by consolidation therapy comprising rituximab and high-dose cyclophosphamide. * Determine the grade 3 or higher non-hematologic toxic effects and overall tolerability of this regimen in these patients. Secondary * Determine the 3-year event-free survival and overall survival of patients treated with this regimen. * Determine the general patterns of CNS and systemic relapse in patients treated with this regimen. OUTLINE: This is a multicenter study. * Dose-intensified CVP induction therapy: Patients receive cyclophosphamide IV and vincristine IV on day 1. Patients also receive oral prednisone on days 1-5 and rituximab IV on days 1 and 8, and high-dose methotrexate IV with leucovorin calcium IV rescue on day 8. Patients receive filgrastim (G-CSF) subcutaneously (SC) once daily beginning on day 3 and continuing until blood counts recover. Treatment repeats approximately every 14 days for 2 courses. * CNS therapy: Patients receive cytarabine intrathecally (IT) with or without hydrocortisone IT on days 1, 4, and 11 of each induction therapy course. Patients with evidence of CNS involvement by lymphoma continue to receive cytarabine IT twice weekly during any induction therapy treatment delay. Patients who demonstrate CSF clearance receive cytarabine IT once weekly for 4 doses and then once every other week for 4 doses during consolidation therapy. Patients with disease progression during induction therapy or persistent CNS involvement by lymphoma are removed from the study. All other patients proceed to consolidation therapy. * Consolidation therapy: Patients receive rituximab IV on day -4 and high-dose cyclophosphamide IV on days -3, -2, -1, and 0. Patients receive G-CSF SC once daily beginning on day 6 and continuing until blood counts recover OR pegfilgrastim SC once on day 6. Patients then receive rituximab IV once weekly for 4 weeks in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed periodically for 3 years. PROJECTED ACCRUAL: A total of 30 patients will be accrued for this study within 3 years.