A patient has a very high white blood count with many blasts in the blood and bone marrow. Esterase stains using both naphthol AS-D chloroacetate and $\alpha$-naphthyl acetate esterase as substrates are both positive. What condition is likely?

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The high WBC count with many blasts and positive esterase stains (both naphthol AS-D chloroacetate and F1F1F1S1​αF1F1F10-naphthyl acetate esterase) suggest a diagnosis of acute myelomonocytic leukemia. Chronic myelogenous leukemia (A) would have a Philadelphia chromosome and the presence of the BCR-ABL fusion protein. Acute lymphoblastic leukemia (B) would have a different set of markers on flow cytometry and would not stain positive for esterase. Hairy cell leukemia (D) would have tartrate-resistant acid phosphatase (TRAP) staining.

A Patient Has a Very High White Blood Count with Many