Total lymphoid irradiation and cyclophosphamide conditioning prior to bone marrow transplantation for patients with severe aplastic anemia.

A preparative regimen, consisting of total lymphoid irradiation and cyclophosphamide, was utilized in 40 patients with severe aplastic anemia undergoing allogeneic marrow transplantation. This regimen was successful in decreasing rejection in these previously transfused patients, as only one patient rejected the marrow graft. Twenty-nine of the 40 transplanted patients are surviving from 1.5 to 59 mo, with a median follow-up of 24 mo. The actuarial survival rate for these heavily transfused patients with aplastic anemia is 72% at 2 yr. This preparative regimen is extremely effective in decreasing rejection following transplantation for severe aplastic anemia. Future efforts in this area must be aimed at the elimination of graft-versus-host disease and control of fatal infections.