CT-409: Determining Causes of Post-Allogeneic HCT Mortality by Day +100: A Single-Center Experience

Abstract

Background Allogeneic hematopoietic cell transplantation (allo-HCT) remains the only potentially curative treatment modality for acute leukemias and other hematologic malignancies and benign blood disorders. In addition to the risk of disease relapse, allo-HSCT is associated with significant treatment related mortality. The first 100 days following allo-HSCT is a particularly high-risk time period, with the reported overall mortality (OM) at 100 days post-allo-HSCT of up to 20%. Methods We conducted a single-center retrospective analysis of patients who underwent allo-HCT, matched unrelated donors (MUD), matched related donors (MRD), and haploidentical-MRD (H-MRD), at Mayo Clinic in Jacksonville, FL, between 01/01/2009 and 03/01/2020. The primary objective of this analysis was to identify the different causes of overall mortality within the first 100 days after allografting and examine the correlation between pre-defined risk factors for allo-HCT and 100-day mortality. Results Our study population consisted of 355 patients (pts) of whom 62 (17.5%) pts were deceased within the first 100 days post-allo-HCT. The median age of pts alive at day +100 was 56 (20–73) years, and 49.8% were male with a median follow-up of 307 (range 100–3429) days. Among the patients deceased by day +100, the median age was 59 (22–74) years; 66% were male. The three most common primary diagnoses were AML (35.5%), MDS (21%), NHL (11.3%). Of these pts, 53 (85.5%) received peripheral blood stem cells, 8 (12.9%) bone marrow, and 1 (1.6%) cord blood. Moreover, 40 (64.5%) received an allo-HCT from a MUD, 16 (25.8%) from an MRD, and 6 (9.6%) from H-MRD. Relapsed/progression was the cause of death in 19.4%, whereas sepsis (30.6%) and acute GVHD (21%) were the most common causes of non-relapse deaths. Conclusions In our study, transplant-related mortality was the main cause of death during the first 100 days after an allogeneic HCT. The main causes of transplant-related mortality were sepsis and acute GVHD.