Hematologic Malignancies USMLE Step 1 Practice Question
A 65-year-old man presents with fatigue and is found to have WBC 12,500/μL on routine labs, with 70% small, mature-appearing lymphocytes. Flow cytometry demonstrates CD5+, CD19+, CD23+ B cells. His CBC from 2 years ago was normal. Vital signs are stable: BP 138/82 mmHg, HR 88/min, RR 16/min, temperature 37.2°C. Physical examination reveals no lymphadenopathy or hepatosplenomegaly. Which of the following is the most likely diagnosis?
Answer choices
- AMarginal zone lymphoma
- BLymphoplasmacytic lymphoma
- CChronic lymphocytic leukemiaCorrect answer
- DFollicular lymphoma
- ESmall lymphocytic lymphoma
- FMycosis fungoides
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