Donor Stem Cell Transplant in Treating Patients With Relapsed Hematologic Cancer

Overview

RATIONALE: Giving low doses of chemotherapy, such as fludarabine and busulfan, before a donor bone marrow or peripheral blood stem cell transplant helps stop the growth of cancer cells. It also stops the patient's immune system from rejecting the donor's stem cells. The donated stem cells may replace the patient's immune system and help destroy any remaining cancer cells (graft-versus-tumor effect). Giving an infusion of the donor's T cells (donor lymphocyte infusion) after the transplant may help increase this effect. Sometimes the transplanted cells from a donor can also make an immune response against the body's normal cells. Giving immunosuppressive therapy after the transplant may stop this from happening. PURPOSE: This phase II trial is studying how well donor bone marrow or peripheral stem cell transplant works in treating patients with relapsed hematologic cancer after treatment with chemotherapy and autologous stem cell transplant.

OBJECTIVES: * Determine the feasibility of non-myeloablative allogeneic hematopoietic stem cell transplantation by demonstrating that the risk of treatment-related mortality during the first 6 months is an acceptable rate of less than 40% in patients with relapsed hematologic malignancies after prior high-dose chemotherapy and autologous stem cell transplantation. * Determine the response rates (disease-specific partial and complete response) in patients treated with this regimen. * Determine the 6-month and 12-month probabilities of response in patients treated with this regimen. * Determine the distribution of time-to-progression in patients responding to this regimen. * Determine the percent donor chimerism in patients treated with this regimen. * Determine the risk of acute and chronic graft-vs-host disease in patients treated with this regimen. * Determine the toxic effects of this regimen in these patients. * Determine the disease-free and overall survival of patients treated with this regimen. OUTLINE: This is an open-label study. * Preparative Regimen: Patients receive fludarabine IV over 30 minutes on days -7 to -3 and busulfan IV over 2 hours every 6 hours (for a total of 8 doses) on days -4 and -3. * Graft vs Host Disease (GVHD) Prophylaxis: Patients who have an HLA-identical donor receive oral (or IV if unable to tolerate oral administration) tacrolimus twice daily on days -1 to 90 followed by a taper\^\* until day 150 and methotrexate IV on days 1, 3, and 6. Patients with a matched related or matched unrelated donor receive oral (or IV if unable to tolerate oral administration) tacrolimus twice daily on days -1 to 180 followed by a taper\^\* as tolerated; methotrexate IV on days 1, 3, 6, and 11; oral mycophenolate mofetil twice daily on days -2 to 60 followed by a taper; and rabbit anti-thymocyte globulin IV over 4-6 hours on days -4 to -1 (for a total of 4 doses). NOTE: \*Tacrolimus may be tapered on days 60-90 if donor chimerism of CD3+ cells is less than 50% at day 60 or patient has progressive disease * Allogeneic Stem Cell Transplantation: Patients undergo allogeneic bone marrow or peripheral blood stem cell transplantation on days 0 and 1. Patients then receive filgrastim (G-CSF) subcutaneously daily beginning on day 7 and continuing until blood counts recover. * Donor Lymphocyte Infusion (DLI): After day 180 (or day 210 for patients without an HLA-identical donor), patients with stable or progressive disease and no active GVHD may receive up to 3 DLIs every 8 weeks. Patients are followed within 2-3 months, every 3 months for 2 years, and then every 6 months for 3 years.