Allogeneic Peripheral Blood Stem Cell Transplantation In 38 Patients With Acute Lymphoblastic Leukemia: A Clinical Analysis

Objective :To retrospectively analyze the results of a consecutive series of 38 acute lymphoblastic leukemia(ALL) patients received allogeneic peripheral blood stem cell transplantation (allo-PBSCT) in our center.Methods: The total study population was 38 adult patients receiving a myeloablative allogeneic peripheral blood stem cell transplantation for ALL in our centers between 2002 and 2008.Of these patients , 25 were male and 13 were female , with a median age of 30.5 (12～56) years. Thirty cases were in the first complete remission (CR1), 8 in second complete remission (CR2) or in relapse before transplant. Allo-PBSCT from HLA identical siblings was performed for 29 patients , HLA matched unrelated PBSCT was performed for 8 patients .Tirty-four patients underwent allo-HSCT with conditioning regimen based on total bobdy irradiation(TBI) and cyclophosphamide(CY), 4 patients received condition regimen based on busulphan and cyclophosphamide (CY) . In order to prophylaxis the graft-versus-host disease (GVHD) ,all patientis receive cyclosporine (CSA) , methotrexate( MTX) and short-course of mycophenolate mofetil regimen. antithymocyte globulin and antiCD25 monoclonal antibodies were added to 8 patients' prophylaxis GVHD regimen who underwent matched unrelated PBSCT. The average follow-up was 32 months.Results: The 3-year overall survival (OS) and disease free survival (DFS) of the 38 cases of ALL was 56.9 % and 46.5 %. We observed an advantage regarding DFS in favor of patients receiving transplantation during their first complete remission (CR1) in comparison with patients receiving transplantation in second CR or who relapsed (P<0.01). Relapse rate and Transplant-related mortality(TRM) for 38 patients are 31.6% and 13.2%, respectively .Acute grade II-IV GVHD developed in 7 patients (18.4%), with chronic GVHD in 16 patients(42.1%). Multi-variate analysis showed the most significant factors associated with long post allo-HSCT survival was that the patient underwent transplantation in CR1 . Overall survival for those patients presenting with central nervous system leukemia is worse than those without involvement.Conclusions: This study confirms that long term survival can be achieved with allo-PBSCT in ALL patients, especially for those in CR1 . Transplant mortality has been significantly reduced by conditioning regimen. Our graft-versus-host disease prophylaxis proved to be effective in controlling the GVHD. According to the COX Model,Disease status and Central nervous system (CNS) involvement have been proposed as adverse prognostic factors.