Effect of donor characteristics on T cell‐replete haploidentical stem cell transplantation over the last 10 years at a single institution

Abstract

One of the most complex issues with haploidentical stem cell transplantation (haplo-SCT) is donor selection, given that multiple haploidentical donors are often available for a given recipient. To develop evidence-based guidance for donor selection in the setting of anti-thymocyte globulinbased haplo-SCT, we performed a prospective cohort study of 512 patients with haematological malignancies who had haplo-SCT to determine which donor variables were most important in favouring transplant outcomes. Increasing donor age was associated with poorer overall survival (OS) [hazard ratio (HR) 1Á08, P = 0Á044]. Female donors to male recipients was significantly associated with higher non-relapse mortality (NRM; HR 2Á05, P = 0Á006). Furthermore, increasing donor age had a higher risk of Grades 3-4 acute graft-versus-host disease (aGVHD; HR 1Á17, P = 0Á005), female donors to male recipients was associated with a higher risk of Grades 2-4 aGVHD (HR 1Á50, P = 0Á022). Sibling donors had superior OS, diseasefree survival, and NRM than parental donors in patients aged <35 years. However, sibling donors had higher NRM than offspring donors in patients aged ≥35 years. A younger donor, usually a young sibling in younger recipients (aged <35 years) or a young offspring in older patients (aged ≥35 years) and avoiding female donors to male recipients should be preferred when multiple haploidentical donors are available.

Survival and late mortality among patients who survived disease‐free for 2 years after stem cell transplantation

“…2,15,25 Our team found the 10-year cumulative incidence of NRM was 14% (95% CI, 11-18) in patients with hematologic malignancies who underwent haplo-SCT. 3 The low NRM at 10 years post-transplant in our studies may be due to median age of our patients was 30 (9-64) years, which was much younger than most of the previous large studies. Meanwhile, the optimization of transplant procedures and the improvement of supportive care technologies may have played an important role.…”

“…There were many previous large retrospective studies showed that the 10‐year NRM of long‐term survivors was 6%–12% in the cohort with a median age of 25–36 years 9,16,53 and 13%–35% in the cohort with a median age of 53–56 years 2,15,25 . Our team found the 10‐year cumulative incidence of NRM was 14% (95% CI, 11–18) in patients with hematologic malignancies who underwent haplo‐SCT 3 . The low NRM at 10 years post‐transplant in our studies may be due to median age of our patients was 30 (9–64) years, which was much younger than most of the previous large studies.…”

“…In 2014, we compared the results of T‐cell‐replete HSCT performed at our centre and found that 5‐year DFS rates were not significantly affected by different donor types, including MSDs, URDs and HRDs 37 . A prospective cohort study in 2021 showed that the preference for a young sibling or a young offspring on donor selection optimised the outcomes of haplo‐SCT in our practice 3 . These studies implied that a haplo‐HSCT regimen with low‐dose ATG may benefit patients in the long run.…”

“…| 617 the outcomes of haplo-SCT in our practice. 3 These studies implied that a haplo-HSCT regimen with low-dose ATG may benefit patients in the long run. The effects of ATG on antigen-presenting cells, such as B cells and dendritic cells, reduce the risk of cGVHD.…”

“…The expansion in donor source availability and development of graft‐versus‐host disease (GVHD) prophylaxis regimens, supportive care technologies and reduced intensity conditioning (RIC) has dramatically increased the number of patients with haematological malignancies being treated with allo‐HSCT 1 . Long‐term survival following allo‐HSCT has also increased over the last decades 2,3 . However, the trends of life expectancy, late complications and prognostic factors that affect late outcomes after allo‐HSCT are poorly understood.…”