Pre-transplant measures of geriatric assessment domains and outcomes of allogeneic hematopoietic cell transplantation in adults aged 75 and older.

Abstract

6563 Background: The upper age limit for allogeneic hematopoietic cell transplantation (HCT) has risen over time, yet prior studies indicate worse outcomes—particularly non-relapse mortality (NRM)—in patients over 70 compared to younger patients (Shahzad, Transplant Cell Ther 2025). As the population ages, we expect the transplant-eligible age range to extend, underscoring the need to identify reliable predictors of outcomes in older adults. Methods: We conducted a retrospective study of all adults aged ≥75 who underwent HCT at Dana-Farber Cancer Institute from January 2008 to August 2024. We evaluated overall survival (OS), progression-free survival (PFS), NRM, and cumulative incidence of relapse (CIR). Guided by geriatric assessment (GA) domains, clinical health data were collected from pre-HCT consent session notes. Log-rank (OS, PFS) and Gray’s tests (NRM, relapse) were used for group comparison; Cox (OS, PFS) and Fine-Gray (NRM, relapse) models were used for multivariable analysis. Results: Sixty-seven patients (median age 76 years, range 75-80) were analyzed; 73.1% were male and 86.6% were White. Acute myeloid leukemia (46.3%) and myelodysplastic syndromes (35.8%) were the most common HCT indications. Neutrophil engraftment occurred in 94% of patients by a median of 15 days (range 3-40). Median follow-up for survivors was 21 months (range 11-125), and median OS was 33 months (95% CI: 18-55). At 18 months, OS was 61% (95% CI: 48-72%), PFS 54% (95% CI: 41-66%), NRM 11% (95% CI: 4.9-21%), and CIR 34% (95% CI: 23-46%). In univariable analysis, age ≥77 (p=0.0095), number of medications ≥15 at HCT consent (p=0.0078), and post-HCT bacterial or fungal infection (p=0.039) were associated with worse OS; similar factors affected PFS (e.g., for patients with bacterial or fungal infection, p=0.049). Diabetes (p=0.0001) and ≥15 medications at time of HCT consent (p=0.001) correlated with higher NRM. On multivariable analysis, age ≥77 (HR 2.44; p=0.028) and ≥15 medications (HR 2.68; p=0.019) significantly predicted worse OS; both factors also predicted inferior PFS. Conclusions: In this relatively large cohort of the oldest HCT recipients, older age, polypharmacy, and comorbidities emerged as likely predictors of worse clinical outcomes. Interestingly, relapse—rather than NRM—was the primary cause of treatment failure, aligning with established links between advanced age and the biology of myeloid malignancies. While the expanding upper age limit for HCT is a promising development for patients ≥75, our data are vital to facilitate informed consent discussions. These findings also underscore the need for robust pre-HCT evaluations, such as assessment of other GA domains via dedicated functional assessments (e.g., IADLs and gait speed) to improve risk stratification. Investigation in a larger cohort (≥70 years) is underway to further explore these results.