High-dose myeloablative therapy with allogeneic hematopoietic
transplantation is an effective treatment for hematologic malignancies,
but this approach is associated with a high risk of complications.
The use of relatively nontoxic, nonmyeloablative, or reduced-intensity
preparative regimens still allows engraftment and the generation of
graft-vs-malignancy effects, is potentially curative for susceptible
malignancies, and reduces the risk of treatment-related morbidity.
Two general strategies along these lines have emerged, based on the
use of (1) immunosuppressive chemotherapeutic drugs, usually a
purine analog in combination with an alkylating agent, and (2) lowdose
total body irradiation, alone or in combination with fludarabine