Non-myeloablative hematopoietic stem cell transplantation is of limited value in advanced or refractory acute...

Allogeneic hematopoietic stem cell transplantation (HSCT) is an effective strategy for preventing relapse of acute myelogenous leukemia (AML). We analyzed the outcome of 31 primary AML patients who received a reduced-intensity conditioning regimen for allogeneic HSCT in first or second remission. Thirty-one AML patients, 20 in first complete remission (FCR), 8 in second complete remission (SCR) and 3 in a partial remission (SPR) were included. All received busulfan 4 mg/kg/d/2 days, fludarabine 30 mg/m(2)/d/3 days and cyclophosphamide 350 mg/m(2)/d/3 days as conditioning regimen. The median number of CD34+ cells infused was 5.6 x 10(6)/kg and 5.2 x 10(6) in FCR and SCR group, respectively. All patients received cyclosporine-A (CsA) and methotrexate as graft vs. host disease (GvHD) prophylaxis. All patients showed myeloid engraftment (neutrophils >0.5 x 10(9)/l) after a median of 13 days in FCR group and 15 days in SCR group. Platelet recovery >20 x 10(9)/l was achieved after a median of 13 days in both groups. Relapse for 20 patients in FCR was 35% compared to 91% for 11 in SCR/SPR (p < 0.05). Conclusions. Reduced-intensity conditioning followed by allogeneic HSCT can induce stable remission in primary AML patients transplanted in FCR. A high relapse rate was documented in patients with refractory or relapsed AML.