Abstract
Clonal hematopoiesis (CH) in long-term survivors of allogeneic hematopoietic cell transplant (HCT) remains largely understudied. Using targeted sequencing, we analyzed peripheral blood samples from 101 patients who survived without relapse for more than 10 years after HCT. The median interval from HCT to sample collection was 13.8 years (range, 10.0-29.8 years). Thirty-six CHs with ≥2% variant allele frequency were detected in 29 patients (28.7%). Complete blood count did not differ according to CH status. Multivariable analysis showed donor age at sampling (odds ratio [OR] 1.06, 95% confidence interval [CI] 1.00-1.12), patients who underwent HCT for chronic myeloid leukemia (CML; OR 7.13, 95% CI 1.38-36.8), and moderate/severe chronic graft-versushost disease at sampling (OR 5.49, 95% CI 1.05-28.7) were significantly associated with CH. Donor age at sampling was significantly higher in patients with pathogenic CH than in those with variants of unknown significance or those without CH (median 56.5 vs 48.0 vs 47.0 years old, p=0.0077). After a median follow-up of 60.0 months after sampling, one patient with CML experienced relapse. Three-year Overall survival (94.2% vs. 92.9%, p=0.800) and cumulative incidence of second cancer (18.0% vs. 14.9%, p=0.410) after CH sampling were not associated with CH status. In conclusion, CH in HCT survivors is common and associated with donor age, transplantation for CML, and chronic graftversus-host disease.