RESUMO
BACKGROUND: High-dose post-transplant cyclophosphamide allows safe and effective use of allografts from haploidentical relatives (siblings, parents and children) in patients undergoing allogeneic blood or marrow transplant (alloBMT). More recently, second- and third-degree relatives have also been shown to be safe allograft donors. An increasing number of older patients undergoing alloBMT have been receiving allografts from haploidentical donors. However, older patients are more likely to have older siblings and children, and older donor age is associated with worse outcomes. OBJECTIVE: In the current study, we report the safety and utility of grandchildren as haploidentical donors and compared with children as donors in patients undergoing alloBMT. METHODS: We compared characteristics and outcomes of alloBMT patients aged 55 years and older with children older than 30 years as donors (C group; n = 276) and those with grandchildren as donors (GC group; n = 40). Because many important baseline characteristics predict outcomes after alloBMT, we performed propensity score matched analysis based on recipient age, alloBMT year, disease, graft source and haematopoietic cell transplantation comorbidity index (HCT-CI). RESULTS: The median age of recipients was 67 years (range 55-79) in the C group and 73 years (range 57-78) in the GC group. More than 70% of recipients in the GC group were older than 70 years, compared with 27% in the C group. The median donor age was 37 years (range 31-52) in the C group and 20 years (range 14-34) in the GC group. More patients in the GC group had HCT-CI scores ≥3 than in the C group (32.5% vs. 23%, p = 0.27). Two-year overall survival did not differ between the two groups (GC 62% vs. C 60%, hazard ratio [HR] 0.96, 95% confidence interval [CI] 0.53-1.75, p = 0.90) despite recipients of allografts from grandchildren being older. The 2-year RFS was 55% in the C group compared with 50% in the GC group (HR 1.05, 95% CI 0.62-1.77, p = 0.85). Non-relapse mortality subdistribution [SD] (SDHR 1.36, 95% 0.70-2.63, p = 0.36), relapse (SDHR 0.72, 95% CI 0.33-1.58, p = 0.42) or relapse-free survival (HR 1.05, 95% CI 0.62-1.77, p = 0.85). Propensity score matching analysis showed no significant differences in 2-year overall survival (GC 64% vs. C 53%; HR 0.77, 95% CI 0.42-1.42, p = 0.40), non-relapse mortality (SDHR 1.26, 95% 0.66-2.41, p = 0.48), relapse (SDHR 0.57, 95% CI 0.21-1.52, p = 0.26) or relapse-free survival (HR 0.94, 95% CI 0.57-1.54, p = 0.81). CONCLUSION: Our results indicate that outcomes of alloBMT patients with grandchild donors are similar to those with child donors, despite recipients' older age and higher comorbidities in the GC group. Grandchildren should be considered when selecting a donor for older alloBMT recipients.
RESUMO
BACKGROUND: Hematopoietic stem cell transplantation (HSCT) is a pivotal treatment for high-risk acute lymphocytic leukemia (ALL), although limited by suitable human leukocyte antigen (HLA)-matched sibling donors (MSD). This study evaluates the impact of donor selection on outcomes in post-HSCT Hispanic B-cell ALL patients. METHODOLOGY: This single-center retrospective study evaluates outcomes in 88 adult Hispanic B-cell ALL patients who underwent haploidentical, MSD, or MUD myeloablative HSCT between 2013 and 2023. RESULTS: Compared to Haploidentical transplants, MSD exhibited worse cumulative incidence of relapse (CIR) (HR = 3.39; P = 0.014) and disease-free survival (DFS) (HR = 2.44; P = 0.048) whereas MUD outcomes did not differ. This effect persisted even when controlling for pre-HSCT stage and Minimal residual disease (MRD) status. In addition, Ph-like was a significant predictor of worse DFS (HR = 3.60; P=0.014) and CIR (HR = 2.97; P=0.035) on multivariate analysis. Older donor age correlated with worse GVHD-free, relapse-free survival (GRFS) in haploidentical transplants (HR = 1.05; P=0.036). CONCLUSION: Our data highlights improved outcomes with younger, haploidentical donors among Hispanic B-cell ALL patients undergoing myeloablative HSCT. This underscores the importance of donor selection in optimizing outcomes for ALL patients.