LAUSR

Objectives To evaluate the frequency and clinicopathologic characteristics of RUNX1 mutations, focusing on patients with acute myeloid leukemia not otherwise specified (AML NOS). Methods Diagnostic samples from 219 patients with AML NOS were analyzed for RUNX1 mutations using standard polymerase chain reaction and direct sequencing. Results Thirty-one RUNX1 mutations were detected in 33 (15.1%) patients. Mutations clustered in the Runt homology (61.3%) and transactivation domains (25.8%). Frameshift mutations were most common (51.6%), followed by missense (41.9%) and nonsense (6.5%) mutations. Patients with RUNX1 mutations had a lower platelet count (P = .013) and shorter relapse-free survival (P = .045) than those without. The presence of RUNX1 and NPM1 or CEBPA mutations was mutually exclusive. A literature review, including our study, showed that patients with RUNX1 mutations were associated with intermediate risk; coexisting mutations such as FLT3-ITD, ASXL1, TET2, and DNMT3A; and a relatively cytogenetic heterogeneity. Conclusions Our findings strengthen previous data concerning RUNX1 mutations in AML and support the notion that RUNX1 mutational status should be integrated into a diagnostic workup of AML, particularly for AML NOS or an intermediate-risk group.