Tacrolimus and Mycophenolate Mofetil in Preventing Graft-Versus-Host Disease in Patients Who Have Undergone Total-Body Irradiation With or Without Fludarabine Phosphate Followed by Donor Peripheral Blood Stem Cell Transplant for Hematologic Cancer

This phase II trial studies how well tacrolimus and mycophenolate mofetil works in preventing graft-versus-host disease in patients who have undergone total-body irradiation (TBI) with or without fludarabine phosphate followed by donor peripheral blood stem cell transplant for hematologic cancer. Giving low doses of chemotherapy, such as fludarabine phosphate, and TBI 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. 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 tacrolimus and mycophenolate mofetil after the transplant may stop this from happening.