Hematologic Malignancies USMLE Step 1 Practice Question
A 54-year-old man presents with three months of progressive fatigue and 8-pound unintentional weight loss. Vital signs show BP 138/86 mmHg, HR 92/min, RR 18/min, temp 37.2°C, SpO2 98% on room air. Physical examination reveals splenomegaly; lymphadenopathy is absent. Laboratory studies show WBC 115,000/mm³ with left shift including myelocytes and basophils, hemoglobin 9.8 g/dL, and leukocyte alkaline phosphatase score of 15 (low). Which diagnosis best explains these findings?
Answer choices
- AAcute myeloid leukemia
- BLeukemoid reaction
- CChronic myelogenous leukemiaCorrect answer
- DPrimary myelofibrosis
- EChronic lymphocytic leukemia
- FAcute lymphoblastic leukemia
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