Eosinophilia, regardless of degree, is related to better outcomes after allogeneic hematopoietic stem cell transplantation

Early-Phase Peripheral Blood Eosinophilia Predicts Lower Overall and Non-Relapse Mortality After Single-Unit Cord Blood Transplantation

Peripheral blood eosinophilia has been associated with the development of graft-versus-host disease (GVHD) and survival after allogeneic hematopoietic cell transplantation (HCT). However, the impacts of eosinophilia on cord blood transplantation (CBT) outcomes remain unclear. The objective of this study was to examine the associations between eosinophilia and overall survival, relapse incidence, non-relapse mortality, and acute and chronic GVHD after single-unit CBT for adults. We retrospectively analyzed the data for 225 adult patients who received single-unit CBT at our institute between March 2004 and March 2020. The cumulative incidence of eosinophilia, defined as an absolute eosinophil count of ≥500 × 10⁶/L in peripheral blood, was 48.9% (95% confidence interval, 42.2% to 55.2%) at 60 days after CBT. Recipient cytomegalovirus seronegative status and higher cryopreserved cord blood CD34⁺ cell dose were significantly associated with a higher incidence of eosinophilia after CBT. Among patients who achieved neutrophil recovery, neutrophil recovery was significantly earlier in patient with eosinophilia compared to those without eosinophilia (P = .016). Serum levels of interleukin-5 at 4 weeks were significantly higher in patients with eosinophilia compared with those without eosinophilia (P = .041). Multivariate analysis, in which the development of eosinophilia was treated as a time-dependent covariate, showed that eosinophilia was significantly associated with lower overall mortality (hazard ratio [HR], .58; P = .034) and non-relapse mortality (HR, .41; P = .029), but not relapse incidence or development of acute or chronic GVHD. Our data suggested that early-phase eosinophilia is a predictor of favorable outcomes in adult patients undergoing single-unit CBT.

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.