The Impact of Clonal Hematopoiesis on Outcomes in Patients with Aplastic Anemia

Over the years, not only have the T-cell mediated immune mechanisms of aplastic anemia (AA) involved in AA development started to become better understood, but there is now also a better understanding of the roles played by somatic mutations, cytogenetic abnormalities and defective telomerase functions and other genetically-related factors. Somatic gene mutations suggestive of clonal hematopoiesis are detected in approximately one third of patients with AA. Recent studies have suggested that some of these may predict a better response to immunosuppressive therapy, whereas others indicate poorer outcomes with higher risks of clonal evolution to myelodysplastic syndrome or acute myeloid leukemia, and that therefore better results may be obtained based on allogeneic stem cell transplantation. Furthermore, recent advances in molecular techniques may be useful in differentiating aplastic anemia from hypocellular myelodysplastic syndrome and other clonal hematopoiesises of indeterminate potential. All of these are summarized in this review which includes further insights into treatment personalization based on the molecular pathogenesis of AA.