Blood smear from a patient with acute monocytic leukemia, differentiated (FAB AML M5B). The predominant promonocytes have abundant cytoplasm with scattered myeloperoxidase-negative azurophilic granules. The nuclei have delicate folds and creases. Nucleoli are inconspicuous (Wright-Giemsa stain).
From Brunning, RD, McKenna, RW. Tumors of the bone marrow. Atlas of tumor pathology (electronic fascicle), Third series, fascicle 9, 1994, Washington, DC. Armed Forces Institute of Pathology.