Retrospective Study of Incidence and Prognostic Significance of Eosinophilia after Allogeneic Hematopoietic Stem Cell Transplantation: Influence of Corticosteroid Therapy

OBJECTIVE The clinical significance of eosinophilia after allogeneic hematopoietic stem cell transplantation is controversial. This study aimed to retrospectively study the impact of eosinophilia on the outcome of allogeneic hematopoietic stem cell transplantation by taking into account the influence of corticosteroid therapy. MATERIALS AND METHODS We retrospectively studied 204 patients with acute myeloid leukemia, acute lymphoblastic leukemia, and myelodysplastic syndrome who underwent allogeneic hematopoietic stem cell transplantation from January 2001 to December 2010. RESULTS The median age was 43 years (minimum-maximum: 17-65 years). Myeloablative conditioning was used in 153 patients and reduced intensity conditioning was employed in 51 patients. Donor cells were from bone marrow in 132 patients, peripheral blood in 34, and cord blood in 38. Eosinophilia was detected in 71 patients and there was no significant predictor of eosinophilia by multivariate analysis. There was no relationship between occurrence of eosinophilia and the incidence or grade of acute graft-versus-host disease when the patients were stratified according to corticosteroid treatment. Although eosinophilia was a prognostic factor for 5-year overall survival by univariate analysis, it was not a significant indicator by multivariate analysis. CONCLUSION These results suggest that the clinical significance of eosinophilia in patients receiving allogeneic hematopoietic stem cell transplantation should be assessed with consideration of systemic corticosteroid administration.