Prognostic significance of chimeric fusion gene analysis in pediatric acute megakaryoblastic leukemia

: Acute megakaryoblastic leukemia in children without Down syndrome (non-DS AMKL) is considered to be a poor prognostic subtype in acute myeloid leukemia. Recently, some chimeric fusion genes were found in pediatric non-DS AMKL; therefore, we attempted to detect chimeric fusion genes RBM15-MKL1, CBFA2T3-GLIS2, and NUP98-KDM5A from 10 pediatric non-DS AMKL diagnostic samples using polymerase chain reaction and Sanger sequencing methods. Two samples were positive for RBM15-MKL1, four had CBFA2T3-GLIS2, and only one case had NUP98-KDM5A. Both RBM15-MKL1-positive patients showed long-term remission after chemotherapy. The eight RBM15-MKL1-negative patients received hematopoietic stem cell transplantation (HSCT). In four CBFA2T3-GLIS2-positive patients, three had HSCT without complete remission and two of themdied. Additional treatment stratification depending on chimeric fusion genes and development of new therapeutic drugs are required for non-DS AMKL.