Peripheral blood and bone marrow evaluation of the patient’s leukemic cells at diagnosis. (A) Wright-Giemsa–stained peripheral blood smear (×100 magnification) at diagnosis, showing abnormal promyelocytes, immature myelomonocytic cells (arrow), and dysplastic neutrophils. (B) Hematoxylin and eosin–stained bone marrow biopsy (×20 magnification; inset ×4) at diagnosis. (C) Bone marrow aspirate smear (×100 magnification). Arrows indicate the dysplastic granulocytes. (D) Flow cytometry of diagnostic bone marrow aspirate. (E) Fusion schematic as identified by RNA sequencing. (F-G) Flow-sorted FISH: FIP1L1-RARA fusion was evaluated in granulocytic cells and CD34⁺ cells by triple color and RARA break-apart FISH. DBD, DNA-binding domain; LBD, ligand-binding domain; NLS, nuclear localization signal.