Allogeneic blood and bone-marrow stem-cell transplantation in haematological malignant diseases: A randomised trial

Background. Autologous transplantation with peripheral blood stem cells (PBSC) results in faster haematopoietic-cell repopulation than with bone marrow. We prospectively compared bone marrow and PBSC for allogeneic transplantation. Methods. Adult HLA-identical sibling donors provided bone marrow and lenograstim-mobilised PBSC. 39 patients with malignant haematological disorders were infused with either bone marrow (n = 19) or PBSC (n = 20) after standard conditioning regimens in a double-blind, randomised fashion. The identity of the infused products for all patients remained masked until 1 year after the last patient had received transplantation. Findings. The PBSC group had significantly faster neutrophil recovery to 0.5 x 10⁹/L (median 17.5 vs 23 days, p = 0.002), and platelet recovery to 20 x 10⁹/L (median 11 vs 18 days, p < 0.0001) and to 50 x 10⁹/L (median 20.5 vs 27 days, p = 0.02) than the bone-marrow group. PBS0 patients were discharged from hospital earlier than were bone-marrow patients (median 26 vs 31 days, p = 0.01). At 4 weeks after transplantation, absolute lymphocytes (0.48 vs 0.63, p = 0.08) and CD25 cells (0.04 vs 0.08, p = 0.007) were higher in the PBSC group, and the proportion of patients with absolute lymphopenia (74% vs 33%, p = 0.03) and CD4 lymphopenia (59% vs 24%, p = 0.05) was significantly higher in the bone-marrow group. There was no significant difference in the occurrence of acute or chronic graft-versus host disease and overall survival. The probability of relapse was significantly higher in the bone-marrow group than in the PBSC group (p = 0.01); all five relapses occurred among bone-marrow recipients. Interpretation. Our small study indicates that PBSCs are better than bone marrow for allogeneic transplantation from HLA-identical siblings in terms of faster haematopoietic and immune recovery, and have the potential to reduce disease recurrence.