Outcome of Chinese patients with chronic myeloid leukaemia (CML) underwent allogeneic bone-marrow transplantation (BMT)

Abstract

Clinical studies have shown that patients with chronic myeloid leukaemia (CML) treated with allogeneic bone-marrow transplantation (BMT) experience not only prolonged disease-free survival but also complete cure in some. Therefore, we followed a cohort of 81 Chinese patients who received allogeneic BMT. Patients and Methods: The donors were either relatives (65 siblings, 1 parent) or unrelated volunteers (15). BMT was performed at a median interval of 11.6 months from diagnosis of CML, and the stages of disease before BMT were: first chronic phase (60 patients), accelerated or second chronic phase in (10 patients), and blastic crisis (11 patients). Three conditioning regimens were employed: Bu-Cy, Cy-TBI, or Bu-Cy-TBI. Standard cyclosporin and short methotrexate protocol were used for acute graft-versus-host disease (GvHD) prophylaxis. Results: There were five graft failures with three after related BMT. Patients after related or unrelated BMT had a comparable rate of neutrophil recovery (median = 22 days), but significant delay in platelet recovery occurred after unrelated BMT (median = 34 vs. 20 days, P < 0.05). The latter also had higher incidence of acute GvHD (73% vs. 41%, P < 0.05), although the incidence of chronic GvHD was not different between groups. At a median follow-up of 43.5 months, patients after related BMT had a significantly better rate of disease-free survival (68% vs. 37.3%, P < 0.05) and overall survival (81% vs. 38.9%, P < 0.05) at 4 years. Subgroup analysis of patients after related BMT showed the outcome was better when they were transplanted at first chronic phase. Multivariate analysis showed that advanced disease (RR = 2.01, 95% CI = 1.48-2.73) significantly worsened the outcome of BMT, whereas the presence of chronic GvHD had a protective effect against relapse and survival (RR = 0.09, 95% CI = 0.02-0.38). Conclusion: Allogeneic BMT is a curative form of treatment for patients with CML. Treatment outcome is best for those who undergo transplants from HLA-matched siblings during the first chronic phase.