High dose therapy and autologous stem cell transplantation for lymphoma: Current status

High dose therapy and autologous stem cell transplantation (ASCT) has been extensively investigated in the treatment of malignant lymphoma, both as salvage treatment, and as a component of first line therapy. Few randomized trials have been conducted, and most evidence is from the retrospective registry-based, or single institution studies. The use of ASCT as salvage therapy for patients with all subtypes of aggressive NHL, or with Hodgkin's disease, who have relapsed after initial chemotherapy, is now a standard of care. In patients with diffuse large B-cell NHL, the survival benefit is restricted to these whose disease is still responsive to 'conventional dose' chemotherapy. The use of ASCT for patients with primary refractory disease is controversial, although retrospective evidence supports its use in patients with Hodgkin's disease, but not those with aggressive NHL. The use of ASCT as a component of first line therapy remains uncertain. For patients with diffuse large B-cell NHL, trials in patients not selected for risk factors have failed to show a survival advantage for ASCT. Trials in patients with 'poor risk' disease as defined by the International Prognostic Index are in progress, and at present, ASCT in this context cannot be recommended except in clinical trials. First remission ASCT for patients with lymphoblastic lymphoma has been compared with conventional dose consolidation therapy. Preliminary results from a single randomized trial show a progression free survival advantage for ASCT in this disease. Although retrospective data have demonstrated encouraging results for this approach in patients with Burkitt's and Burkitt-like NHL, the excellent results of recent dose intensive, non-transplant regimens for these diseases suggest, that first remission ASCT should not be considered a routine for these patients. The potential long term toxicity of ASCT in patients with Hodgkin's disease, and the favorable outcome for this patient group precludes its widespread use as part of the first line therapy, although one randomized trial addressing this issue is in progress.