Allogenic bone marrow transplantation for chronic myelomonocytic leukemia in childhood: A report from the European Working Group on Myelodysplastic Syndrome in Childhood

Purpose: To evaluate the role of allogeneic bone marrow transplantation (BMT) in children with chronic myelomonocytic leukemia (CMML). Patients and Methods: Forty-three children with CMML given BMT and reported to the European Working Group on Myelodysplastic Syndrome in Childhood (EWOG-MDS) data bose were evaluated. in 25 cases, the donor was a human leukocyte antigen (HLA)-identical or a one-antigen-disparate relative, in four cases a mismatched family donor, and in 14 a matched unrelated donor (MUD). Conditioning regimens consisted of total-body irradiation (TBI) and chemotherapy in 22 patients, whereas busulfan (Bu) with other cytotoxic drugs was used in the remaining patients. Results: Six of 43 patients (14%), five of wham received transplants from alternative donors, failed to engraft. There was a significant difference in the incidences of chronic graft-versus-host disease (GVHD) between children transplanted from compatible/one-antigen-mismatched relatives and from alternative donors (23% and 87%, respectively; P < .005). Probabilities of transplant-related mortality for children given BMT from HLA-identical/one-antigen-disparate relatives or from MUD/mismatched relatives were 9% and 46%, respectively. The probability of relapse for the entire group was 58%, whereas the 5-year event-free survival (EFS) rate was 31%. The EFS rate for children given BMT from an HLA-identical sibling or one-antigen-disparate relative was 38%. In this latter group, patients who received Bu had a better EFS compared with those given TBI (62% v 11%, P < .01). Conclusion: Children with CMML and on HLA-compatible relative should be transplanted as early as possible. Improvement of donor selection, GVHD prophylaxis, and supportive care ore needed to ameliorate results of BMT from alternative donors. (C) 1997 by American Society of Clinical Oncology.