Standard Risk Assessment Tools Fall Short to Assess Risk in Transplant Patients

Document Type

Conference Proceeding

Publication Date

2-1-2024

Publication Title

Transplantation and Cellular Therapy

Abstract

Introduction: The HCT-CI (Hematopoietic Cell Transplantation-specific Comorbidity Index) and the Disease Risk Index (DRI) Assessment Tool are models used for pre-transplant risk assessment. HCT-CI ≥3 is associated with higher non-relapse mortality (NRM) and lower overall survival (OS). The DRI was developed to predict overall survival per disease status. Objectives: This retrospective study was done to understand reasons for increased mortality in transplant patients at our center in 2021 compared to 2020 by comparing HCT-CI and DRI of transplant patients between the two years. Methods: This was an IRB-approved study. Relevant patient comorbidities, disease characteristics, and transplant-related data were collected. Patients were risk stratified using the online DRI Assessment Tool. Data was analysed using R version 4.3.1, and a p-value less than 0.05 was considered statistically significant. Results: A total of 165 transplants were reviewed. Patient characteristics are elucidated in Table 1. Mean age at HCT in 2020 was 59.8 and 59.3 in 2021. Allogeneic HCT was done in 38.4% of HCT in 2020 and 37% in 2021. HCT-CI was ≥3 in 68.5% in 2020 and 70.7% in 2021. DRI was high or very high in 20.5% patients in 2020 and 20.6% in 2021. The 2-year OS of Allo HCT was worse in 2021 compared to 2020 although not statistically significant (50.6% vs. 57.7% respectively, p=0.52, figure 1 A). The cumulative incidence of relapse in Allo HCT at year 1 and 2 were significantly less in 2021 compared to 2020 (Table 2). However, there was a numerically higher incidence of non-relapse mortality (Table 2 and Figure 1 B). The hazard for NRM for patients who underwent Allo HCT was 2.89 compared to Auto (p=0.046). The hazard for relapse for patients with high DRI was 4.24 (p<0.001) times relative to patients with low DRI, controlling for year, HCT type, HCT-CI, and demographics. The hazard for NRM for patients with high DRI was 2.60 (p=0.070), however 16 patients (12 in 2021 and 4 in 2020) were excluded from this analysis as they underwent transplants for diseases that are currently not included in the DRI assessment tool. These included aplastic anemia (AA), inherited bone marrow failure syndromes (BMF), solid tumors, primary CNS lymphomas, mycosis fungoides and hemophagocytic lymphohistiocytosis (HLH). Of these 8 patients, 7 died due to causes other than disease relapse. Conclusion: In this small single-center retrospective analysis, 2021 has statistically significant less relapse by second year with a trend towards higher NRM and worse OS in 2021 (though not statistically significant, possibly limited by sample size). The DRI or another tool however could not be used in those patients. Most predictive models are mainly applied to hematological malignancies, but are not specific for inherited or acquired BMF disorders, HLH or solid tumor malignancies. We sent a proposal to CIBMTR for further consideration to help with this unmet need.

Volume

30

Issue

2

First Page

S125

Find It @ Sladen

Share

COinS