https://orcid.org/0000-0001-8814-230X
Key Points
HSCT from younger haplo donors provided better overall survival and lower nonrelapse mortality in older patients compared with CBT.
The finding highlights the importance of considering donor and patient age in transplantation strategies, as outcomes vary by age groups.
Allogeneic hematopoietic stem cell transplantation (HSCT) from HLA-matched donors is the gold standard. However, haploidentical stem cell transplantation using posttransplant cyclophosphamide (PTCY-haplo) and cord blood transplants (CBTs) are alternatives when HLA-matched donors are unavailable. Using the Japanese Registry data, we evaluated the impact of haploidentical donor age on posttransplant outcomes by comparing PTCY-haplo and CBT. We analyzed data for 5,161 patients aged 16-70 who received their first HSCT for acute leukemia, myelodysplastic syndrome, or chronic myeloid leukemia. Haploidentical donors were categorized as "younger" (<40 years) or "older" (≥40 years), and the patients were divided into younger (<50 years) and older (≥50 years) cohorts. In the older cohort, PTCY-haplo from younger donors had better overall survival (OS) (55.5% vs. 50.8%, P = 0.006), lower nonrelapse mortality (NRM) (17.3% vs. 28.6%, P < 0.001), and higher relapse rates (33.0% vs. 24.9%, P = 0.017) compared with CBT. PTCY-haplo from older donors had comparable OS (44.1% vs. 50.8%, P = 1.00), NRM (27.3% vs. 28.6%, P = 1.00), and relapse (29.2% vs. 24.9%, P = 0.90) to CBT. In the younger cohort, PTCY-haplo from younger and older donors showed comparable OS, NRM, and relapse to CBT. Compared to PTCY-haplo, cumulative incidence of acute graft-versus host disease (GVHD) was higher in CBT, regardless of donor age, in the older cohort. However, acute GVHD was lower in PTCY-haplo from younger donors in the younger cohort compared with CBT. PTCY-haplo from younger donors to older patients offers better clinical outcomes compared with CBT.
