Engraftment and survival after unrelated-donor bone marrow transplantation: a report from the National Marrow Donor Program

We analyzed engraftment of unrelated-donor (URD) bone marrow in 5246 patien ts who received transplants facilitated by the National Marrow Donor Progra m between August 1991 and June 1999. Among patients surviving at least 28 d ays, 4% had primary graft failure (failure to achieve an absolute neutrophi l count > 5 x 10(8)/L before death or second stem-cell infusion). Multivari ate logistic regression analysis showed that engraftment was associated wit h marrow matched at HLA-A, HLA-B, and DRB1; higher cell dose; younger recip ient; male recipient; and recipient from a non-African American ethnic grou p. More rapid myeloid engraftment was associated with marrow serologically matched at HLA-A and HLA-B, DRB1 match, higher cell dose (in non-T-cell-dep leted cases), younger recipient, recipient seronegativity for cytomegalovir us (CMV), male donor, no methotrexate for graft-versus-host disease prophyl axis, and transplantation done in more recent years. A platelet count highe r than 50 x 10(9)/L was achieved by 47% of patients by day 100. Conditional on survival to day 100, survival at 3 years was 61% in those with platelet engraftment at day 30, 58% in those with engraftment between day 30 and da y 100, and 33% in those without engraftment at day 100 (P < .0001). Factors favoring platelet engraftment were higher cell dose, DRB1 allele match, re cipient seronegativity for CMV, HLA-A and HLA-B serologically matched donor , and male donor. Secondary graft failure occurred in 10% of patients achie ving initial engraftment, and 18% of those patients are alive. These data d emonstrate that quality of engraftment is an important predictor of surviva l after URD bone marrow transplantation. (C) 2000 by The American Society o f Hematology.