Allogeneic bone marrow transplantation for leukemia with marrow grafts treated by counterflow centrifugation

Eighty consecutive patients were transplanted with human leukocyte antigen (HLA)-identical sibling marrow for acute myelogenous leukemia (AML, N = 29), acute lymphoid leukemia (ALL, N = 23), or chronic myelogenous leukemia (CML, N = 28). Donor marrow was depleted of lymphocytes using counterflow centrifugation. Median age of the recipients was 31 years. Pretransplant conditioning consisted of cyclophosphamide and fractionated total body irradiation (TBI). Graft failure occurred in 4 of 77 evaluable patients (5%). The probability of acute graft-versus-host disease (GVHD) > or = grade 2 at day 100 after transplantation was 15%. The projected 3-year estimate of extensive chronic GVHD was 12%. The projected 3-year probability of relapse was 30% in transplants for AML in first complete remission (CR1), 35% after transplantation for ALL in CR1, and 38% after transplantation for CML in first chronic phase (CP1). The projected 3-year probability of leukemia-free survival (LFS) was 56% after transplantation for AML-CR1, 42% in patients transplanted for ALL-CR1, and 49% after transplantation for CML-CP1. The chance of relapse was significantly reduced in a cohort of 72 standard risk patients conditioned with a regimen intensified by the addition of anthracyclines. This resulted in DFS at 4 years after BMT of 63% compared to 39% in a historical control group. Enrichment of the donor marrow with NK-cells did not increase the incidence of GVHD, but did neither decrease the relapse rate after BMT. In bone marrow transplantation for leukemia, counterflow centrifugation is a useful technique for the prevention of GVHD. Further efforts should be made to reduce relapse-rate, particularly in high risk patients.