No disadvantage in outcome of using matched unrelated donors as compared with matched sibling donors for bone marrow transplantation in children withacute lymphoblastic leukemia in second remission

Purpose: We evaluated the outcome of children with acute lymphoblastic leuk emia(ALL) in second remission (2CR), comparing bone marrow transplantation (BMT) using either matched sibling donors or unrelated donors (URDs). Patients and Methods: A total of 65 patients, aged 2 months to 20 years at BMT, with ALL in 2CR underwent allogeneic BMT at seven Nordic centers durin g 1990 to 1997. Of the first relapses, 85% were in bone marrow 46% occurred on therapy, and 54%, off therapy. The preparative regimens were cyclophosp hamide plus total-body irradiation +/- antithymocyte/antilymphocyte globuli n, busulfan plus cyclophosphamide +/- antithymocyte/antilymphocyte globulin , or cytarabine plus total-body irradiation. Of the allografts, 37 were fro m HLA-matched siblings and 28 were from URDs. Results: In the sibling versus URD graft recipient groups, the posttranspla ntation 5-year event-free survival was 39% versus 54% (P = .4), the estimat ed posttransplantation relapse rate was 76% versus 40% (P = not significant [NS]), and the toxic death rate was 19% versus 11% (P = NS). The incidence of significant (grade 2 to 4) acute graft-versus-host disease (GVHD) was 3 8% versus 64% (P < .05) and was 14% versus 32% (P < .10) for severe (grade 3 to 4) acute GVHD; the incidence of chronic GVHD was 26% versus 57% (P < . 05) and was 13% versus 22% (P = NS) for extensive chronic GVHD in the sibli ng and URD groups. Conclusion: BMT with matched URD allografts offers at least equal survival for children with ALL in 2CR,as compared with allografts from matched sibli ng donors. URD allografts were not associated with a higher toxic mortality rate, although both acute and chronic GVHD were more frequent with URD. in dications for using matched URD allografts in ALL 2CR can be considered the same as for using matched sibling donors. (C) 2001 by American Society of Clinical Oncology.