Bone marrow transplantation - New developments in the last decade

The last decade has witnessed very significant developments in the field of bone marrow transplantation (BMT), resulting in the improved safety and availability of this procedure. The expansion of international registries of voluntary, unrelated donors, the establishment of banks of fetal cord blood stem cells, as well as improved technology for transplantation of stem cells derived from partially matched family members, offer this treatment to patients hitherto not eligible for BMT. In addition to better donor availability, there has been a change in the concept regarding the role of BMT in the treatment of cancer: the understanding that the transplanted donor cells are capable of mounting an immunological assault against the host malignant cells. This goal can be achieved without fully destroying the patient's bone marrow stem cells and thus prepare the patient for transplantation with a reduced dose intensity of the myelotoxic drugs. Such nonmyeloablative conditioning increases the safety of the procedure. These developments have resulted in a vast expansion of the patient population eligible for BMT, including patients older than those who could have benefited from conventional allogeneic BMT with its associated high mortality in the older age groups, and those lacking fully matched family donors. This article surveys these developments and reviews the clinical indications for BMT in selected malignancies that are evidence-based. The role of BMT and its timing, in the light of new alternative solutions already in the market, is also discussed. Such critical evaluation is particularly warranted in view of the vastly higher rate of BMT per capita in Israel, as compared to other western countries, and given the late side effects inherent in the procedure.