Morphologic features of AML with cuplike nuclei. (A) Blasts are medium-sized and have prominent nuclear invaginations, and scant to moderate cytoplasm with a few, fine azurophilic granules (Wright-Giemsa bone marrow aspirate smear; original magnification, × 1000). Image was obtained using an Olympus BX41 microscope (Olympus, Melville, NY) equipped with a 100×/1.25 numeric aperture oil objective; was acquired using a Spot Insight color camera 3.2.0 (Diagnostic Instruments, Sterling Heights, MI) and Image Pro Plus software version 3.2 (Media Cybernetics, Silver Spring, MD); and was processed using Adobe Photoshop CS version 7 (Adobe Systems, San Jose, CA). (B) Condensed collections of mitochondriae are present within the invaginated nuclear pockets (transmission electron microscopic examination; scale bar indicates 500 nm). Image was obtained using a JEOL 1200 EXII electron microscope (JEOL, Tokyo, Japan) at 20 000× magnification, and was processed using Adobe Photoshop CS version 7.