Determinants of refined GvHD-free, relapse-free survival after reduced-intensity allogeneic hematopoietic cell transplantation in older patients with myeloid malignancies.

BACKGROUND: Older patients with AML/MDS have a poor prognosis with alloHCT as the only curative option. However alloHCT is challenging given its high TRM. Recently, a composite endpoint of GRFS was proposed to define transplant success. A single centre retrospective analysis was performed to determine the main variables influencing GRFS.

PATIENTS AND METHODSMETHODS: 91 consecutive patients≥ 60 years (median 64 years, range 60-74) with AML/MDS who received reduced-intensity alloHCT during 2001-2017 analysed. Disease risk index (DRI) at HCT was low/intermediate in 47pts (52%) and high in 44 pts (48%).

RESULTS: After median follow-up for survivors of 56 months (range 7-144), 37 (40.6%) patients were alive. The OS, LFS and GRFS were 61.4%, 58.1%, 49.1% at 1 year and 35.5%, 32.3% and 23.1% at 5 years, respectively. The 1-year and 5-year incidences of NRM and relapse were 26.9%, 21.3% and 47.9% and 35.4%, respectively. In univariate analysis, high DRI was the strongest factor for worse OS (HR 2.121; p = 0.049), LFS (HR 1.924; p = 0.0123) and GRFS (HR 2.319; p = 0.0005). The donor age ≥ 62 years had a negative impact on OS (HR 2.110; p = 0.0345) and GRFS (HR 2.014; p = 0.0341). High DRI (HR 2.652; p = 0.0003) and donor age (HR 2.304; p = 0.0257) retained its significance in multivariate analysis for GRFS.

CONCLUSION: A significant portion of older patients with myeloid malignancies survive alloHCT without experiencing GRFS event with DRI as the main determinant of outcome. Negative impact of donor age≥ 62 years suggests preference of a young donor, regardless of being related or unrelated.