The role of autologous bone marrow transplantation in cancer treatment

Autologous bone marrow transplantation (ABMT) has been increasingly used in the treatment of malignant diseases. Since myelosuppression is one of the major dose limiting factors in cancer chemotherapy, ABMT is effective for hematologic reconstitution after marrow-lethal intensive therapy, which increases the anti-tumor effect. Diseases for which ABMT is indicated are selected on the basis of sensitivity to escalation of drug and radiation dose. These diseases include non-Hodgkin's lymphoma, leukemia, small cell carcinoma of the lung, melanoma, neuroblastoma, metastatic breast cancer and Ewing's sarcoma. Phase I and phase II studies have demonstrated that dose escalation to several times the conventional dosage may be feasible with the use of ABMT. Clinical trials of intensive therapy plus ABMT have produced encouraging results in terms of response rate and long-term survival for selected patients with poor-prognosis malignant diseases which are resistant or refractory to conventional forms of cancer therapy. When these preliminary results are analysed, it is apparent that the outcome of this treatment modality is affected by several factors such as disease status or tumor burden at the time of ABMT, the anti-tumor effect of the pretransplant intensive therapy and the extent of bone marrow invasion by tumor cells. Since ABMT is not yet well established in comparison with allogeneic bone marrow transplantation, carefully designed clinical trials will be required in order to assess the efficacy of ABMT.