Autologous bone marrow transplant in the treatment of acute leukaemia

For a minority of patients with acute leukaemia, usually in children and predominantly with acute lymphoblastic leukaemia, existing chemotherapy protocols are curative. For a minority of the remaining group myeloablative chemoradiotherapy supported by allogeneic marrow from an HLA-matched donor can cure the disease. Major efforts are being made to free the potential benefit of this approach from the limitations imposed by the associated immune-biological complications, and limited donor availability. In the last decade the resurgence of autologous transplantation in remission has been a major new source of hope for further progress. Many groups have produced encouraging results, which now that they have substantial follow-up, suggest that this approach is altering the normal pattern of relapse. Almost all the experience, however, while producing consistent results, at least in AML, is anecdotal. The possibility of selection bias, particularly by the time-censoring effect, cannot be excluded, and prospective controlled trials are needed. The data available suggest which investigations could be expected to yield clear results. Other questions, particularly whether or not to purge the marrow, are only practical to investigate in well-defined patient subgroups. The opportunity to identify predictive parameters in this new clinical setting, using the more powerful techniques now becoming available should not be missed. National and international trials now in progress will yield crucial data in the next 2 or 3 years.