Biology of chronic myeloid leukemia and its relevance to autologous bone marrow transplantation

Because of the relative resistance of chronic myeloid leukemia (CML) progenitors to most standard cytotoxic agents, marrow-ablative doses of drugs or radiotherapy followed by allogeneic bone marrow transplantation (BMT) remain the only curative option for patients with CML. However, the effectiveness of allogeneic BMT is limited by the toxicity of graft-versus- host disease and the lack of histocompatible donors for most patients. Although it avoids these major obstacles of allogeneic BMT, autologous BMT has not been effective in CML because of the inability to purge CML from the autologous graft and the absence of the allogeneic immunologic antitumor activity. Techniques that allow the clinical isolation of normal stem cells from CML marrow combined with novel posttransplantation immunotherapeutic approaches should make autologous BMT a curative treatment for CML in the near future.