Background: To study intensive postremission therapy in adult patients with acute myeloid leukemia myeloablative therapy followed by allogeneic or unpurged autologous bone marrow transplantation (BMT) was compared with high-dose cytosine-arabinoside/daunorubicin (HDAC) consolidation.
Patients and methods: 148 de novo AML patients of maximum 50 years (median 36 years, range 16 to 50) were enrolled in the trial. Following induction and early consolidation chemotherapy consisting of daunorubicin, cytosine-arabinoside and VP-16 (DAV), patients with an HLA-identical sibling underwent allogeneic BMT. The other patients received (by randomization or patient's decision) either HDAC or high-dose busulfan plus cyclophosphamide followed by autologous BMT.
Results: Hundred and five 105 (70.9%) patients achieved a complete remission. The event-free survival rates after intensive postremission therapy after 72 months were: after BMT (24 patients) 62% (95% confidence interval +/- 19%), after HDAC (44 patients) 36 +/- 16% and after autologous BMT (12 patients) 18 +/- 22%. Thus allogeneic BMT was superior to autologous BMT (p = 0.04), as was HDAC compared to autologous BMT, although not significantly so (p = 0.15). Patients receiving 2 cycles of HDAC had a better 6-year event-free survival rate (47%) and a lower relapse rate (50%) than patients who received only 1 course (29% and 70% respectively).
Conclusions: High-dose busulfan/cyclophosphamide followed by unpurged autologous BMT early after achieving CR had no advantage over high-dose ara-c/daunorubicin. Two cycles of HDAC yielded better results than 1 cycle. The highest event-free survival rate was reached with myeloablative therapy followed by allogeneic BMT.