Marrow transplantation following busulfan and cyclophosphamide for chronic myelogenous leukaemia in accelerated or blastic phase

Between July 1984 and October 1987, 21 patients with chronic myelogenous leukaemia in an accelerated or blastic phase were treated with 16 mg/kg of busulfan and 120 mg/kg of cyclophosphamide followed by infusion of bone marrow from an HLA-identical sibling donor. The regimen was well tolerated. Except for one individual with severe marrow fibrosis all patients achieved a complete remission. Only one patient relapsed. Seven of 13 patients transplanted in an accelerated phase and five of eight transplanted in a blastic phase are alive without Philadelphia chromosomes between 8 and 48 months (median 29 months) following transplantation. The estimated probability of relapse-free 3-year survival is 55%. These results indicate that busulfan and cyclophosphamide combined with allogeneic marrow transplantation exert a potent anti-leukaemic effect in patients in the accelerated or blastic phase of CML.