Hematologic Malignancies USMLE Step 1 Practice Question
A 52-year-old man presents to his primary care physician with a 3-month history of progressive fatigue and persistent lower back pain. He denies fever, weight loss, or night sweats. Vital signs are stable. Physical examination reveals no lymphadenopathy or hepatosplenomegaly. Laboratory studies show: hemoglobin 9.2 g/dL, creatinine 2.1 mg/dL, calcium 11.8 mg/dL, albumin 2.8 g/dL, and a normocytic anemia. Serum protein electrophoresis demonstrates an M-spike, and serum free light chains reveal an abnormal kappa/lambda ratio. Bone marrow biopsy shows 35% clonal plasma cells with evidence of lytic bone lesions on skeletal survey. Which of the following is the most likely diagnosis?
Answer choices
- AWaldenstrom macroglobulinemia
- BMultiple myelomaCorrect answer
- CAL amyloidosis
- DMonoclonal gammopathy of undetermined significance (MGUS)
- EImmunoglobulin light chain disease
- FAcute lymphoblastic leukemia with circulating plasma cells
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