A case of KMT2A–SEPT9 fusion–associated acute megakaryoblastic leukemia

Acute megakaryoblastic leukemia (AMKL) constitutes ∼5%–15% of cases of non–Down syndrome AML in children, and in the majority of cases, chimeric oncogenes resulting from recurrent gene rearrangements are identified. Based on these rearrangements, several molecular subsets have been characterized providing important prognostic information. One such subset includes a group of patients with translocations involving the KMT2A gene, which has been associated with various fusion partners in patients with AMKL. Here we report the molecular findings of a 2-yr-old girl with AMKL and t(11;17)(q23;25) found to have a KMT2A–SEPT9 fusion identified through targeted RNA sequencing. A KMT2A–SEPT9 fusion in this subset of patients has not previously been reported.