Clinical Information

Acute myeloid leukemia (AML) is a genetically heterogeneous group of neoplasms. While cytogenetic aberrations detected at the time of diagnosis are the most used prognostic feature, approximately 50% of AML cases show a normal karyotype, which is considered an intermediate-risk feature. Within this group, FLT3 variants are considered indicators of poor prognosis. However, in the absence of a FLT3 variant, the presence of a NPM1 variant is associated with a more favorable prognosis. A NPM1 alteration is a common finding in de novo AML (25%-30% of cases) and consists of small insertion (typically 4 base pairs) or deletion/insertion events involving exon 12. Three variants are highly recurrent, termed types A, B, and D, and together account for approximately 90% of NPM1 alterations in de novo AML. Thus, in patients with newly diagnosed AML, those with normal karyotype, no FLT3 variant, and a NPM1 alteration are considered to have a better prognosis than patients in the same group with neoplasms lacking a NPM1 alteration. Furthermore, the presence of a NPM1 alteration serves as a sensitive marker for evaluating minimal disease and therapeutic response following treatment.