RESUMO
OBJECTIVE: To evaluate the efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the conditioning of different intensities for acute leukemias of ambiguous lineage (ALAL). METHODS: A total of 38 ALAL patients were treated with two conditioning of different intensities in our hospital from March 2002 to August 2010. The standard conditioning included TBI + Cy or Bu + Cy, intensified conditioning included Fludarabine + Ara-C + TBI + Cy. Cyclosporine A (CsA) and methotrexate (MTX) were administered in patients with human leukocyte antigen-matched sibling donor. And CsA, MTX plus antihuman thymocyte globulin and/or mycophenolate were used in all patients with HLA-mismatched related donor and unrelated donors transplants for graft-versus-host disease (GVHD) prophylaxis. COX regression was used to evaluate the prognostic factors of ALAL. RESULTS: Among 38 ALAL patients, 19 received the standard conditioning while another 19 the intensified conditioning. All patients achieved hematopoietic reconstitution. The 5-year overall survival (OS) and the disease-free survival (DFS) were 35.5% and 25.7% respectively. The 5-year OS rates were 20.2% and 48.1% (P = 0.233) and DFS 6.5% and 43.1% (P = 0.031) in the standard and intensified conditioning groups respectively. The 5-year cumulative relapsing incidence was 58.9% in all patients and 87.6% vs 30.4% in the standard and intensified conditioning groups respectively (P = 0.003). Through a COX regression model for univariate analysis, the intensified conditioning and chronic GVHD were protective factors for DFS (P = 0.001, 0.031). CONCLUSION: The intensified conditioning in ALAL patients undergoing allo-HSCT may improve the long-term patient survival and decrease the relapse of leukemia. The graft versus leukemic effect has some efficacy in ALAL patients undergoing allo-HSCT.