A comparison of clinical outcomes between HLA allele matched and 1 - 2 alleles mismatched unrelated allogeneic bone marrow transplantations

OBJECTIVE: To compare the clinical outcomes between HLA allele matched (HLA-M) and 1 approximately 2 alleles disparity mismatched (HLA-mis) unrelated allogeneic bone marrow transplantation (URD-BMT). METHODS: Thirty-nine patients received HLA-M and 21 received HLA-mis URD-BMT for the treatment of acute leukemia, chronic myeloid leukemia in chronic phase (CP) and myelodysplastic syndromes (MDS) in our hospital between November 1998 and December 2002. Conditioning regimen was Bu 16 mg/kg plus CTX 120 mg/kg, and mycophenolate mofetil (MMF), CsA and MTX were given to prevent aGVHD. RESULTS: Thirty-eight of the HLA-M group and 18 of the HLA-mis group were engrafted successfully. The median follow-up duration was 11 (2.5 - 52.0) months for HLA-M group and 9 (2 - 46) months for HLA-mis group. The 3-year probabilities of disease-free survival (DFS) for HLA-M and HLA-mis group were (79.2 +/- 7.1)% and (45.8 +/- 15.5)%, respectively (P < 0.05). Grade II - IV aGVHD occurred in 10 (26.3%) patients in HLA-M group and 6 (33.3%) in HLA-mis group, respectively (P > 0.05). CONCLUSION: URD-BMT is an effective modality for the treatment of leukemia and MDS. The outcome after URD-BMT can be optimized by matching the HLA-A, B and DR alleles between the donor and recipient.