A recent study by Murthy et al. evaluated the clinical outcomes of patients with myelodysplastic syndrome receiving an allogeneic hematopoietic stem cell transplant (allo-HCT) from older matched sibling donors (MSDs) or young human leukocyte antigen–matched unrelated donors (MUDs). Results of this retrospective study were recently published in the journal JAMA Oncology.1
The retrospective cohort study evaluated data of 1,761 adults (50+ years old) with myelodysplastic syndrome who underwent allo-HCT using either an older MSD (n=646) or younger MUD (n=1,115). The median follow up was for 48 months between Jan1, 2011 and Dec 31, 2017. The primary outcome of the study was disease-free survival (DFS), and secondary outcomes included overall survival (OS), relapse and nonrelapse mortality, acute graft-vs-host disease (GVHD), chronic GVHD, and GVHD-free relapse-free survival.
The data analysis revealed that transplants from older MSDs resulted in a lower rate of DFS as compared to younger MUDs (HR [95% CI]: 1.17 [1.02-1.34]; p =0.02). However, no significant difference in OS rate was observed between these groups (HR [95% CI]: 1.13 [0.98-1.29]; p=0.07). Patients treated with allo-HCT from older MSDs showed significantly higher relapse mortality (HR[95% CI]: 1.62 [1.32-1.97]; p<0.001) and a lower rate of GVHD-free relapse-free survival beyond 12 months after allo-HCT compared to young MUDs (HR [95% CI]: 1.42 [1.02-1.98]; p=0.04). However, donations from older MSDs were also associated with lower nonrelapse mortality (HR [95% CI]: 0.76 [0.59-0.96]; p=0.02), lower acute GVHD (HR [95% CO]: 0.52 [0.42-0.65]; p<0.001) and less chronic GVHD (HR [95% CI]: 0.77 [0.64-0.92]; p=0.005),
In conclusion, allo-HCT from younger MUDs improved DFS outcomes and lowered the relapse-related mortality in patients with myelodysplastic syndrome. However, allo-HCT was inferior compared to MSDs in regards to nonrelapse mortality and different GVHD outcomes. Both forms of transplants seem to have their own advantages and disadvantages.