Neoplasia USMLE Step 1 Practice Question
A 3-year-old boy presents with an abdominal mass discovered by his parents. Vital signs are stable (BP 95/60, HR 110, RR 24, Temp 37°C, SpO2 98%). Abdominal ultrasound reveals a unilateral 5-cm left renal mass. Laboratory studies show hemoglobin 10.2 g/dL; urinalysis is negative for hematuria. The child has received no prior chemotherapy. Nephrectomy specimen demonstrates primitive blastemal, stromal, and epithelial components. Which immunohistochemical marker is most likely positive?
Answer choices
- APSA
- BCalcitonin
- CCD117
- DWT1Correct answer
- EMUC2
- FPAX8
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