Cytogenetic abnormalities in NPM1-mutated acute myeloid leukemia

Abstract

NPM1 mut acute myeloid leukemia (AML) has been identified as a distinct entity of myeloid neoplasms according to the 2017 European LeukemiaNet (ELN) guidelines. It confers a favorable prognosis regardless of cytogenetic abnormalities. We evaluated 418 newly diagnosed AML patients to test the validity of this hypothesis. Seventy-four patients with NPM1 mut AML showed a good response to induction and a relatively favorable prognosis. Abnormal karyotypes were observed in 15 patients. Chromosomal abnormalities were significantly associated with a worse prognosis in NPM1 mut AML patients (5-year overall survival (OS): 38.9 ± 12.9%, p = .037; event-free survival (EFS): 33.3 ± 12.2%, p = .043, respectively). Four patients with abnormal karyotypes who underwent allogeneic hematopoietic stem cell transplantation (alloHSCT) during CR1 had longer survival than those who received chemotherapy only. Multivariable analysis revealed abnormal karyotypes independently predicted OS and EFS among NPM1 mut AML patients. In summary, cytogenetic abnormalities are strong prognostic indicators in NPM1 mut AML. Therefore, they should be classified accordingly, and alloHSCT should be performed on selected patients during CR1.