Allo-HSCT outcomes stratified by donor type and age in AML/MDS

Results from a retrospective, multicenter study evaluating outcomes of fully human leukocyte antigen (HLA)-matched allogeneic hematopoietic stem cell transplantation (allo-HSCT), stratified by donor type and donor age, in 293 older patients (≥60 years) with acute myeloid leukemia (AML) or myelodysplastic syndromes (MDS) were published in Leukemia Research by Prejzner et al. Outcomes assessed included overall survival (OS), non-relapse mortality (NRM), and relapse-free survival (RFS) at 2 and 5 years post-allo-HSCT.

Key data: Of 293 patients, 221 received matched unrelated donor (MUD) grafts (median donor age 31 years) and 72 received matched sibling donor (MSD) grafts (median donor age 61 years). With a median follow-up of 21 months, 2-year OS was higher in MUD vs MSD transplant recipients (62% vs 47%; p = 0.02), with a trend toward improved 5-year OS (p = 0.07). While relapse rates were similar in MUD vs MSD transplant recipients (31% vs 36%), 5-year RFS was numerically higher in MUD vs MSD transplant recipients (p = 0.08). NRM at 5 years was numerically lower in MUD vs MSD transplant recipients (22.2% vs 30.5%; p = 0.23). In a multivariable analysis, among patients with data on donor age (n = 221), MUD transplants from donors aged <30 years were independently associated with reduced 2-year mortality risk (adjusted hazard ratio [aHR], 0.43; 95% confidence interval [CI], 0.23–0.76; p = 0.004) and reduced 2-year NRM risk (aHR, 0.24; 95% CI, 0.06–0.67; p = 0.006).

Key learning: In this retrospective study, MUD allo-HSCT with donors aged <30 years was associated with lower 2-year mortality and NRM compared with MSD allo-HSCT, suggesting that younger MUD may be preferable to older MSD when selecting donors for patients aged ≥60 years with AML or MDS.