Current status of allogeneic transplantation for aggressive non-Hodgkin lymphoma

To provide a succinct update on the role of allogeneic stem cell transplantation (allo-SCT) in the management of patients with aggressive lymphomas. To clarify the indications for allogeneic transplantation vis-à-vis autologous transplant and to discuss the rationale and potential benefits of reduced intensity conditioning (RIC), nonmyeloablative (NMA) transplant, T-cell depletion and variations in graft vs. host disease (GVHD) prophylaxis.

Considerable effort has been spent in developing transplant regimens with reduced toxicity and reduced GVHD. The role of allogeneic transplantation has also been redefined in light of advances in lymphoma classification, diagnostic methods, particularly PET scan and advances in transplant technology. Haplo and umbilical cord blood SCT allow identification of a donor for nearly all patients.

In diffuse large B-cell lymphoma, the outcome of allo-SCT depends on patient characteristics and chemosensitivity. It is useful after failure of auto-SCT and in partial responses to salvage therapy. Allo-SCT may be the treatment of choice for advanced T-cell and natural killer cell lymphoma and for adult T-cell leukemia-lymphoma. Prophylactic or preemptive donor lymphocyte infusion may be useful, but requires controlled studies. RIC and NMA conditioning have reduced early toxicity but are associated with increased risk for disease recurrence. Promising data have been reported from a novel conditioning regimen combining NMA with ibritumomab tiuxetan. T-cell depletion reduces chronic GVHD but has some increase in rate of recurrence. Rapamycin may be associated with reduction in risk for disease recurrence.