Combination Chemotherapy and Total-Body Irradiation Followed by Peripheral Stem Cell or Bone Marrow Transplantation in Treating Patients With Acute Lymphoblastic Leukemia

RATIONALE: Drugs used in chemotherapy use different ways to stop cancer cells from dividing so they stop growing or die. Peripheral stem cell transplantation may be able to replace immune cells that were destroyed by chemotherapy and radiation therapy. Sometimes the transplanted cells are rejected by the body's normal tissues. Mycophenolate mofetil and donor white blood cells may prevent this from happening. PURPOSE: Phase I/II trial to determine the effectiveness of combination chemotherapy and total-body irradiation followed by peripheral stem cell transplantation in treating patients who have acute lymphoblastic leukemia.

OBJECTIVES: * Determine if a one-year disease free survival of 40% and a day 200 transplant-related mortality of less than 25% can be achieved in patients with high-risk acute lymphoblastic leukemia in complete remission treated with a nonmyeloablative conditioning regimen comprising fludarabine and total body irradiation followed by allogeneic peripheral blood stem cell or bone marrow transplantation. * Evaluate the efficacy and toxicity of donor lymphocyte infusion in the treatment of minimal residual disease after nonmyeloablative allografting in these patients. OUTLINE: This is a multicenter study. Patients receive a nonmyeloablative conditioning regimen comprising fludarabine IV on days -4 to -2 and total body irradiation (TBI) on day 0. Children undergo allogeneic peripheral blood stem cell transplantation (PBSCT) or bone marrow transplantation after TBI on day 0. Adults undergo filgrastim (G-CSF)-mobilized allogeneic PBSCT after TBI on day 0. Patients also receive graft-versus-host disease (GVHD) prophylaxis therapy comprising oral cyclosporine twice daily on days -3 to 56 and then tapered and oral mycophenolate mofetil once at 5-10 hours after transplantation on day 0 and then twice daily on days 1-27. Patients who have no evidence of grade 2 or greater acute GVHD or clinically extensive chronic GVHD, have been off GVHD prophylaxis therapy for 1-2 weeks, and have stable or increasing minimal residual disease after discontinuation of GVHD prophylaxis therapy receive donor lymphocyte infusion (DLI) IV over 30 minutes. DLI repeats every 4 weeks for a total of 3 doses (if necessary). Patients without a history of CNS leukemia and patients with a history of CNS leukemia previously treated with prophylactic craniospinal irradiation receive methotrexate (MTX) or cytarabine (ARA-C) intrathecally (IT) for a total of 2 doses before transplantation and for a total of 6 doses beginning on day 32 after transplantation. Patients with a history of CNS leukemia not previously treated with craniospinal irradiation undergo craniospinal irradiation for 11 days before conditioning regimen and then MTX or ARA-C IT for a total of 6 doses beginning on day 32 after transplantation. Male patients also undergo testicular radiotherapy for 7 days. Patients are followed at 1, 2, 3, 6, 12, 18, and 24 months. PROJECTED ACCRUAL: A total of 30 patients (20 adults and 10 children) will be accrued for this study within 2 years.