Young Donors Improve DFS in Allo-HCT Patients With Myelodysplastic Syndrome

Disease-free survival and lower relapse rates were observed in patients with myelodysplastic syndrome who were undergoing allogeneic hematopoietic cell transplantation (allo-HCT) from younger matched unrelated donors (MUDs) compared with older matched sibling donors (MSDs), according to a study published in JAMA Oncology.¹

The minimum age for MSDs was 50 years, and the maximum age for MUDs was 35 years.

Investigators assessed 1761 patients over 5 years. They found DFS in the MUD group (n = 1115) was 30.6% (95% CI, 27.4%-33.8%) compared with 24.9% in the MSD group (95% CI, 21.1%-28.9%; P = .01; n = 646)

This retrospective study analyzed data from patients who were 50 years or older with myelodysplastic syndrome who underwent allo-HCT from an older MSD or younger MUD from the Center for International Blood and Marrow Transplant Research database between January 1, 2011, and December 31, 2017. Median follow-up was 48 months. Analysis of the data occurred between January 8, 2019, and December 30, 2020. The primary outcome of the study was DFS, and the secondary outcomes were overall survival (OS), relapse, nonrelapse mortality, acute graft-vs-host disease (GVHD), chronic GVHD, and GVHD-free relapse-free survival.

The median age of patients was 66.5 years (range, 50.4-80.9) in the MUD cohort and 64.9 years (range, 50.2-77.6) in the MSD cohort. Sixty-six percent of patients were male.

The OS was 37.1% (95%CI, 33.6%-40.6%) for patients undergoing allo-HCT with younger MUDs and 33.9% (95%CI, 29.6%-38.4%) for patients undergoing allo-HCT with older MSDs (P = .19). It is important to note that difference between MUDs and MSDs was not statistically significant in OS analysis (P = .07). Relapse was 37.3% (95% CI, 34.3%-40.3%) for patients in the MUD group vs 49.6% (95% CI, 45.5%-53.7%; P < .001) for patients in the MSD group. Nonrelapse mortality, defined as death without recurrent or progressive disease after allo-HSCT, was 32.2% (95% CI, 29.0%-35.4%) in the younger MUD group vs 25.5% (95% CI, 21.8%-29.4%) with older MSD group (P = .002).

Acute GVHD of grades 2 to 4 occurred in 48.3% (95%CI, 45.4%-51.3%) of patients undergoing allo-HCT with younger MUDs and 39.3% (95%CI, 35.5%-43.1%) of patients undergoing allo-HCT with older MSDs (P = .001). Acute GVHD of grades 3 to 4 occurred in 20.0% (95% CI, 17.7%-22.4%) and 17.2% (95% CI, 14.4%-20.3%) of the MUD and MSD groups, respectively.

Chronic GVHD in patients undergoing allo-HCT with younger MUDs was 53.9% (95%CI, 50.7%-57.1%) and 49.0% (95%CI, 44.9%-53.0%) for patients undergoing allo-HCT with older MSDs (P = .08). The MSD group showed lower GVHD-free, relapse-free survival after 12 months of allo-HCT (HR, 1.42; 95% CI, 1.02-1.98; P = .04).

These results favor younger MUDs for consideration in the donor selection for patients with myelodysplastic syndrome.

_Reference

_{Guru Murthy GS, Kim S, Hu ZH, et al. Relapse and disease-free survival in patients with myelodysplastic syndrome undergoing allogeneic hematopoietic cell transplantation using older matched sibling donors vs younger matched unrelated donors. JAMA Oncol. 2022;e216846. doi:10.1001/jamaoncol.2021.6 846}