Long-term survival in patients with peripheral T-cell non-Hodgkin lymphomas after allogeneic hematopoietic stem cell transplant.

Peripheral T-cell non-Hodgkin lymphomas (T-NHL) are rare diseases, with a worse prognosis compared to their B-cell counterparts. Allogeneic hematopoietic stem cell transplant may have a role in the treatment of relapsed/refractory disease or high-risk histologies in the upfront setting. However, there is limited information on the efficacy of allogeneic transplant for these diseases, as well as what factors may predict outcomes. We therefore performed a retrospective study of 34 patients who received an allogeneic transplant for the treatment of T-NHL at a single center between 1 January 1992 and 31 December 2009. The median follow-up for survivors was 45 months (range 9-160 months). The 2-year overall survival (OS) was 0.61 (95% confidence interval [CI]: 0.43-0.75) with a plateau at 28 months. Ki-67 expression ≤ 25% was predictive of improved OS (p < 0.01), and transplant in complete remission was predictive of a decreased cumulative incidence of events (p = 0.04). Three patients received a donor leukocyte infusion, and two patients demonstrated a response, supporting a graft-versus-lymphoma effect. These data demonstrate that allogeneic transplant is a viable option for the treatment of T-NHL and merits prospective evaluation.