The clinical study of non-T-depleted human leukocyte antigen mismatched hematopoietic stem cell transplants with total body irradiation for the treatment of leukemia

Objective To explore the feasibility of HLA mismatched hematopoietic stem cell transplants with conditioning regime containing TBI for the treatment of leukemia.Methods Between April 2002 and January 2007,eight patients received hematopietic stem cell transplants(HSCT)with HLA mismatched family donors,including 1 chronic monomyelocytic leukemia(CMML),3 acute nonlymphocytic leukemia(ANLL),and 4 acute lymphocytic leukemia(ALL).Stem cell sources were G-CSF mobilized peripheral blood(n=2)or bone marrow plus peripheral blood(n=6).Four patients were conditioned with TBI and cyclophosphamide(CY),the other four patients were conditioned with TBI and fludarabine(FLU),of whom 7 were conditioned with additional antithymocyteglobulin(ATG),and 1 was conditioned with additional CD25 antibody.Graft versus host disease(GVHD)prophylaxis regimen consisted of cyclosporin A(CSA)and methotrexate(MTX)and mycophenolate mofetil(MMF).Results Eight patients received a mean number of 7.39(6.27~12.46)×108/kg MNC from donor stem cell.The mean time of ANC0.5×109/L was day 11(11~13),and BPC20.0×109/L was day 13(11~21).All the patients got engraftment successfully and attained CR.Acute Ⅰ~Ⅱ GVHD occurred in 5 patients,no acute Ⅲ~Ⅳ GVHD occurred and extensive chronic GVHD did in 2 patients.All the patients were alive and only one patient relapsed after 3~53 months follow-up.Conclusion TBI-based conditioning regimen appears to be safe and effective for non-T-depleted HLA mismatched hemotopoietic stem cell transplants,especially for high-risk and second transplant patients.