title: Hemophagocytosis by leukemic megakaryoblasts in acute myeloid leukemia (megakaryoblastic) with t(1;22)(p13;q13);RBM15-MKL1.
abstract: Acute megakaryoblastic leukemia is a rare variant of acute myeloid leukemia, whereby leukemic blasts display characteristic morphologic and phenotypic features indicating megakaryocytoid differentiation. A distinct entity characterized by the t(1;22)(p13;q13) translocation, resulting in the RBM15-MKL1 fusion oncogene, has been recently recognized. This is predominantly a disease afflicting infants and displays characteristic clinical features. We present a case of acute megakaryoblastic leukemia with t(1;22)(p13;q13) along with a discussion of the current understanding of the molecular biology of RBM15-MKL1. This case also displayed striking and unusual morphologic appearances including extensive hemophagocytosis by leukemic blasts, which has not been previously reported for this particular type of leukemia.
authors.affiliation: Department of Haematology & Oncology, Royal Manchester Children's Hospital, Manchester, UK. daniel_wiseman@hotmail.com
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Wiseman
authors.forename: Denise K
authors.initials: DK
authors.lastname: Bonney
authors.forename: Robert F
authors.initials: RF
authors.lastname: Wynn
mesh_terms: D002878:Chromosomes, Human, Pair 1; D002892:Chromosomes, Human, Pair 22; D005260:Female; D006801:Humans; D007223:Infant; D007947:Leukemia, Megakaryoblastic, Acute / Q000235:genetics* / Q000473:pathology; D051359:Lymphohistiocytosis, Hemophagocytic / Q000209:etiology*; D055016:Megakaryocyte Progenitor Cells / Q000473:pathology*; D015514:Oncogene Proteins, Fusion / Q000235:genetics; D014178:Translocation, Genetic
chemical_list: C532421:OTT-MAL fusion protein, human; D015514:Oncogene Proteins, Fusion