Hematologic Malignancies USMLE Step 1 Practice Question
A 71-year-old man presents for evaluation after routine blood work reveals WBC 38,000/mm³. He reports feeling well with no constitutional symptoms. Vital signs are normal: BP 138/82, HR 76, RR 16, Temp 36.8°C, SpO₂ 98% on room air. Peripheral blood smear shows numerous small mature lymphocytes and characteristic smudge cells. Flow cytometry demonstrates CD20-positive, CD23-positive, CD5-positive B cells. Lymph node examination is unremarkable. Which of the following is the most likely diagnosis?
Answer choices
- AHairy cell leukemia
- BMantle cell lymphoma
- CChronic lymphocytic leukemiaCorrect answer
- DAcute myeloid leukemia
- EAcute lymphoblastic leukemia
- FFollicular lymphoma
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