High-dose therapy and stem cell transplantation in follicular lymphoma.

Indolent follicular lymphomas are diseases which are generally incurable with conventional therapy. Although patients can survive for prolonged periods, the median duration of first remissions is about 2.5 years, and subsequent remissions progressively shorten with time. High-dose therapy with hematopoietic stem cell support leads to prolonged disease-free and overall survival in a subset of patients with aggressive non-Hodgkin's lymphoma. Mounting evidence suggests similar findings for selected patients with indolent follicular non-Hodgkin's lymphoma. It is still unclear as to when this approach should be used; however, inferior results have been seen in heavily pretreated patients. In contrast, encouraging results are being reported in patients undergoing such treatment early in the course of their disease. Despite these data, many patients continue to relapse, and investigations are now focused on eradication of minimal residual disease, allogeneic transplantation, novel ablative regimens, and improvements in stem cell purging.