Role of allogeneic transplantation in low-grade lymphoma and chronic lymphocytic leukemia

Indolent lymphoproliferative disorders are incurable with conventional chemotherapy. Exploring the potential of allogeneic transplantation to eradicate disease has therefore been of interest for some time. This review reports on recent developments in this field to evaluate the current status of stem cell transplantation in the management of these conditions.

Most recent studies examine the application of reduced intensity regimens in follicular non-Hodgkin's lymphoma and chronic lymphocytic leukemia. Interest is particularly focused on assessing the potency of the allogeneic graft-versus-malignancy effect, whether achieved by T cells infused at the time of transplant, or by the administration of exogenous donor lymphocytes at relapse or progression following transplant. Furthermore, the discovery of molecular/genetic factors that permit identification of patients with poor prognosis chronic lymphocytic leukemia has led to interest in identifying whether the allogeneic effect can overcome the impact of these factors.

Encouraging evidence is accumulating for the efficacy of reduced intensity transplantation in indolent lymphoproliferative disorders. Allogeneic graft-versus-malignancy effects can be demonstrated and durable responses to donor lymphocytes are being reported. More follow-up is required, however, before the curative potential of allogeneic transplantation can be assessed. The appropriate timing of transplant and the choice of regimen remains unclear.