Patients with acute myeloid leukemia (AML) have experienced an improvement in outcome with current intensification regimens.However, some subsets of patients may have an increased likelihood of relapse.We report the preliminary results of a pilot study utilizing busulfan, cyclophosphamide and etoposide (BuCEt) followed by autologous hematopoietic stem cell transplantation (HSCT) in patients with AML in first or greater complete remission.Adults aged 15 yr or older with AML in CR1 or greater who did not have a suitable donor were eligible for this study.The source of hematopoietic stem cells (HSC) was either the bone marrow or the peripheral blood.Bone marrow was harvested from the posterior iliac crests under general anesthesia.Peripheral blood stems cells (PBSC) were harvested after a mobilization regimen of etoposide 60 mg/kg ideal body weight i.v. (hour 0-18), cyclophosphamide 3 g/m2 i.v. in two divided doses (hour 24-25 and 30-31), paclitaxel 200 mg/ m2 i.v. (hour 48-51) (TEC), and granulocyte colony-stimulating factor (G-CSF) 5 gg/kg/day i.v. from hour 60 until recovery of the absolute neutrophil count (ANC >1 x 109/1) and collection of the PBSC.The conditioning regimen consisted of busulfan 1 mg/kg/day p.o., administered 4 times each day for 4 days (days -7, -6, -5 and -4), etoposide 60 mg/kg ideal body weight i.v. over 18 h on day -3, and cyclophosphamide 45 mg/kg i.v. over 1 h times two doses administered 6 h apart on day -2 (BuCEt).We utilized a combination of TEC along with G-CSF to mobilize and harvest PBSC.This regimen was successful especially among patients with AML in CR1, likely because these individuals had received less prior chemotherapy.The transplantation regimen administered in this study was tolerated well and was associated with few adverse effects, and only one heavily pretreated patient died from sepsis in the early posttransplantation period.Patients who underwent an autologous bone marrow transplantation after a failed attempt at PBSC mobilization had a prolonged period of transfusion dependency.The results of this pilot trial suggest that BuCEt is easy to administer and well tolerated.Together with autologous HSCT, it can produce long-term LFS in 49% of patients at standard or high risk for relapse.Further study is warranted.