Outcomes of allogeneic stem cell transplantation in patients with paroxysmal nocturnal hemoglobinuria with or without aplastic anemia

Objective The aim of this study was to evaluate the long-term outcomes of allogeneic stem cell transplantation (SCT) in patients with paroxysmal nocturnal hemoglobinuria (PNH) with or without aplastic anemia (AA). Method A total of 33 patients with PNH clones who underwent allogeneic SCT were analyzed. Results After a median follow-up of 57 months (range, 6.0-151.3), the 5-year estimated overall survival rate was 87.9 ± 5.7%. Four patients died of transplant-related mortality (TRM). With the exception of one patient with early TRM, 32 patients were engrafted. Two patients who had developed delayed graft failure received a second transplant and recovered. The cumulative incidences of acute graft-versus-host disease (GVHD) (≥grade II) and chronic GVHD (≥moderate) were 27.3 ± 7.9% and 18.7 ± 7.0%, respectively. Twenty-one patients receiving SCT with reduced-intensity conditioning (RIC) had available follow-up data for PNH cell population for the first 6 months post-transplant. Analysis of these data revealed that the PNH clones disappeared within approximately 2 months. Conclusion RIC regimen was sufficient to eradicate PNH clones with sustained donor-type engraftment after allogeneic SCT. Therefore, application of allogeneic SCT with RIC should be considered in patients with PNH, in accordance with the severity of the underlying bone marrow failure. This article is protected by copyright. All rights reserved.