Clonal Cytogenetic Evolution in Relapse of Myeloid Hematological Neoplasms After Allogeneic Stem Cell Transplantation
Simple Summary Disease recurrence after allogeneic stem cell transplantation remains the principal cause of treatment failure in patients with myeloid malignancies. One possible explanation is the acquisition of additional genetic alterations by malignant cells over time. In this study, we investigated the emergence of cytogenetic changes at relapse and their association with prior treatment exposure and clinical outcomes. Nearly half of the patients developed cytogenetic changes at relapse. These alterations occurred more frequently in individuals with complex cytogenetic abnormalities at diagnosis, suggesting that an unstable genomic background may predispose further clonal diversification. In contrast, prior chemotherapy, conditioning regimen, and donor type were not associated with the emergence of new abnormalities. Although patients with cytogenetic changes showed a lower early response rate, long-term survival outcomes were not significantly affected. Overall, our findings suggest that cytogenetic alterations at relapse may primarily be driven by disease-intrinsic biological features rather than treatment-related genomic damage.