General Pathology USMLE Step 1 Practice Question
A 58-year-old man presents with a painful violaceous scalp mass that developed 8 years after radiation therapy for brain lymphoma. Vital signs show BP 138/82, HR 88, RR 16, Temp 37.2°C, SpO2 98%. Physical examination reveals a 3-cm indurated nodule with surrounding edema. Biopsy demonstrates a malignant vascular neoplasm with high mitotic activity. Imaging shows no osseous involvement. Which immunohistochemical stain most likely confirms the diagnosis?
Answer choices
- APSA
- BPECAM 1 CD31Correct answer
- CTRAP
- DNeurofilament
- EGFAP
- FHMB-45
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