Alemtuzumab Plus Fludarabine and Melphalan With or Without Cyclosporine, Mycophenolate Mofetil, and Low-Dose Total-Body Irradiation Therapy Followed by Donor Peripheral Stem Cell Transplant in Treating Patients With Hematologic Cancer

RATIONALE: Giving low doses of chemotherapy, monoclonal antibodies, and radiation therapy before a donor 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 when they do not exactly match the patient’s blood. The donated stem cells may replace the patient’s immune system and help destroy any remaining cancer cells (graft-versus-tumor effect). Sometimes the transplanted cells from a donor can also make an immune response against the body’s normal cells. Giving cyclosporine and mycophenolate mofetil before transplant may stop this from happening.

PURPOSE: This phase I/II trial is studying the side effects of alemtuzumab, fludarabine, and melphalan with or without cyclosporine, mycophenolate mofetil, and total-body irradiation before donor peripheral blood stem cell transplant and to see how well they work in treating patients with relapsed or refractory hematologic cancer.