ABSTRACT
PURPOSE: We assessed the three-alkylator combination of busulfan, melphalan and thiotepa or TBI, melphalan and thiotepa conditioning for allogeneic stem cell transplantation in 7 adult patients with refractory or relapsed acute leukemias. MATERIALS AND METHODS: Six patients were transplanted for acute myeloid leukemia, one for acute lymphoblastic leukemia and included 5 of relapsed refractory, 2 of relapsed after first-BMT. All but 1 cases received G-CSF stimulated CD34+ allogeneic peripheral blood progenitor cells (PBPCs) in addition to stimulated allogeneic marrow. RESULTS: All patients except one engrafted (median time to ANC >0.5 10 (9)/L=11days, to platelets >30 X 10 (9)/L=14 days) successfully and complete remission was obtained in 6 patients. Grade I-II acute GVHD and controllable regimen-related toxicity especially oral mucositis (grade II-III) developed in all cases, but 2 patients including one second- allogeneic BMT patient expired early by transplant-related toxicity of hepatic or multiorgan failure along the course of sepsis. CONCLUSION: Although the observation period on these cases are limited, the data presented show that the combination of busulfan, melphalan and thiotepa is tolerable as a preparative regimen for allogeneic marrow transplantation in high-risk leukemic patients. We think that these encouraging results need to be confirmed in prospective studies in the future.