Outcomes of transplantation with matched-sibling and unrelateddonor bone marrow in children with leukaemia

Background For most conditions amenable to bone-marrow transplantation, grafts from HLA-matched but unrelated donors have yielded poorer results than those obtained from matched-sibling donors. We assessed this pattern in the light of improvements in donor selection and posttransplant supportive care. Methods We reviewed transplant outcome in 103 consecutive patients with childhood leukaemia who underwent allogeneic bone-marrow transplantation with HLA-matched sibling marrow (n=52) or matched unrelated donor marrow (n=51) between May, 1990, and March, 1996, at St Jude Childrenʹs Research Hospital. Findings Analysis of engraftment, frequency of procedurerelated complications, and disease-free survival revealed no advantage from use of matched-sibling marrow. The 2-year disease-free survival estimate for standard-risk recipients of matched-sibling marrow was 81 [8·1]% compared with 73 [12·1]% in the unrelated donor marrow group (p=0·77). In the high-risk category, patients with a matched-sibling donor had a 2-year disease-free survival of 31 [11·6]%, compared with 32 [15·1]% among recipients of matched unrelated donor marrow (p=0·87). Interpretation We believe this improved result with unrelated donor marrow is a consequence of recent innovations in histocompatibility matching, prevention of graft-versus-host disease (GvHD), and antiviral prophylaxis. We suggest that such grafts can now be used in patients at both standard and high risk without compromising treatment outcome.