Outcome of Lower-Intensity Allogeneic Transplantation in Non-Hodgkin Lymphoma after Autologous Transplantation Failure

We studied the outcome of allogeneic hematopoietic stem cell transplantation after lower-intensity conditioning regimens (reduced-intensity conditioning and nonmyeloablative) in patients with non-Hodgkin lymphoma who relapsed after autologous hematopoietic stem cell transplantation. Nonrelapse mortality, lymphoma progression/relapse, progression-free survival (PFS), and overall survival were analyzed in 263 patients with non-Hodgkin lymphoma. All 263 patients had relapsed after a previous autologous hematopoietic stem cell transplantation and then had undergone allogeneic hematopoietic stem cell transplantation from a related (n = 26) or unrelated (n = 237) donor after reduced-intensity conditioning (n = 128) or nonmyeloablative (n = 135) and were reported to the Center for International Blood and Marrow Transplant Research between 1996 and 2006. The median follow-up of survivors was 68 months (range, 3-111 months). Three-year nonrelapse mortality was 44% (95% confidence interval [CI], 37%-50%). Lymphoma progression/relapse at 3 years was 35% (95% CI, 29%-41%). Three-year probabilities of PFS and overall survival were 21% (95% CI, 16%-27%) and 32% (95% CI, 27%-38%), respectively. Superior Karnofsky Performance Score, longer interval between transplantations, total body irradiation-based conditioning regimen, and lymphoma remission at transplantation were correlated with improved PFS. Allogeneic hematopoietic stem cell transplantation after lower-intensity conditioning is associated with significant nonrelapse mortality but can result in long-term PFS. We describe a quantitative risk model based on pretransplantation risk factors to identify those patients likely to benefit from this approach.

Key Words: Allogeneic, Relapse, Reduced-Intensity