Neoplasia USMLE Step 1 Practice Question
A 47-year-old man presents with a rapidly enlarging, painless deep thigh mass. Vital signs include BP 128/82 mmHg, HR 92/min, RR 16/min, temperature 37.2°C, and SpO2 98% on room air. MRI demonstrates a 6 cm heterogeneous soft tissue mass with areas of necrosis. Core needle biopsy shows spindle cell proliferation suspicious for sarcoma. Laboratory studies reveal normal CBC and metabolic panel. Which immunohistochemical marker is most consistent with mesenchymal differentiation?
Answer choices
- AVimentinCorrect answer
- BS100
- CCytokeratin
- DPSA
- EChromogranin
- FCD45
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