High-dose therapy in multiple myeloma and primary amyloidosis: an overview.

Autologous stem cell transplantation is a reasonable approach for patients younger than 70 years and should be discussed with each patient before instituting alkylating agent therapy. Ideally, it should be done in a clinical trial. Although most patients relapse, it does provide a modest prolongation of survival. The major needs are an improved preparative regimen before transplantation and the removal of myeloma cells and, more importantly, their precursors from the peripheral blood. Conventional allogeneic transplantation is associated with too high a mortality rate at present and cannot be recommended. Efforts must be directed toward reducing transplant-related mortality by T-cell depletion or other means. The preparative regimen must be improved, because most patients relapse after transplantation. The use of dendritic cells and vaccines is an important area of research. The role of autologous transplantation in primary amyloidosis (AL) is indeterminate at present. Longer follow-up evaluation of patients who have undergone transplantation is needed. Patient selection is a critical aspect. Stem-cell transplantation should be performed in a clinical trial for primary AL.