A Case of Acute Myeloid Leukemia with Myelodysplasia-Related Changes, SET-NUP214 Fusion, and Complex Karyotype

Background: The SET-NUP214 fusion formed by cryptic t(9;9)(q34;q34) or del(9)(q34.11q34.13) is a rare gene rearrangement. This rearrangement has been reported mostly in T-cell acute lymphoblastic leukemia, but only rarely in acute myeloid leukemia (AML). The acute leukemia cases with the SET-NUP214 fusion gene show typical immunophenotype, karyotype, and poor treatment response. However, the cytogenetic or genetic changes in AML with SET-NUP214 fusion are not well understood. Methods: The diagnosis was made based on a combination of the morphology, immunophenotyping, multiplex reverse transcriptase-polymerase chain reaction, FISH, karyotype, Sanger sequencing, next-generation sequencing, and microarray analysis. Results: The author reports a rare case of AML with myelodysplasia-related changes, SET-NUP214 fusion gene, and complex karyotype that was resistant to induction chemotherapy, making diagnosis and treatment difficult. Conclusions: Further studies, including cytogenetic and molecular analyses, are needed to determine the pathophysiology and clinical significance for this rare gene rearrangement.