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 transplantatio n (BMT) in children with chronic myelomonocytic leukemia (CMML). Patie nts and Methods: Forty-three children with CMML given BMT and reported to the European Working Group on Myelodysplastic Syndrome in Childhoo d (EWOG-MDS) data bose were evaluated. in 25 cases, the donor was a hu man leukocyte antigen (HLA)-identical or a one-antigen-disparate relat ive, in four cases a mismatched family donor, and in 14 a matched unre lated donor (MUD). Conditioning regimens consisted of total-body irrad iation (TBI) and chemotherapy in 22 patients, whereas busulfan (Bu) wi th other cytotoxic drugs was used in the remaining patients. Results: Six of 43 patients (14%), five of wham received transplants from alter native donors, failed to engraft. There was a significant difference i n the incidences of chronic graft-versus-host disease (GVHD) between c hildren transplanted from compatible/one-antigen-mismatched relatives and from alternative donors (23% and 87%, respectively; P < .005). Pro babilities 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 fo r the entire group was 58%, whereas the 5-year event-free survival (EF S) rate was 31%. The EFS rate for children given BMT from an HLA-ident ical 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. I mprovement of donor selection, GVHD prophylaxis, and supportive care o re needed to ameliorate results of BMT from alternative donors. (C) 19 97 by American Society of Clinical Oncology.