Allogeneic stem cell transplantation for patients with acute lymphoblastic leukemia: comparison of reduced-intensity conditioning versus myeloablative conditioning

Abstract

Allogeneic stem cell transplantation (SCT) is a curative treatment option for acute lymphoblastic leukemia (ALL). However, myeloablative (MA) SCT involves considerable toxicity, particularly in elderly patients, graft–versus-host disease (GVHD), and the immune deficiency state that accompanies the procedure. Reduced-intensity conditioning allogeneic stem cell transplantation (RIST) is being used for patients who are not able to endure MA conditioning because of the advanced age or other medical conditions. Also, RIST depends on graft-versus-tumor effects for their eradication of malignant cells. There have been fewer studies conducted in patients with ALL, and all are retrospective. In addition, an evaluation of outcomes suggests that the GVL effect is more effective against myeloid malignancies, such as acute and chronic myeloid leukemia, and malignancies of mature B cells, such as low-grade non-Hodgkin`s lymphoma and multiple myeloma, but less so with a more undifferentiated B-cell disease, such as pre-B ALL, especially if not in remission.Nevertheless, a few small studies have been reported that suggested that there may well be a role for RIC-SCT even in ALL. Considering the progress in adult ALL therapy and despite better disease control, high toxicity and limited improvement in DFS in older adult patients, a detailed analysis is needed to determine if RIC can improve outcome of older adults with ALL. Therefore, we have conducted a direct comparison of the outcomes of RIC-SCT and myeloablative SCT in the treatment of patients exhibiting adults ALL