Neoplasia USMLE Step 1 Practice Question
A 28-year-old man presents to the emergency department with acute right scrotal pain and swelling that began 3 days ago. He reports no recent trauma or fever. On examination, a firm, non-transilluminating 3 cm mass is palpated within the right testis. Vital signs are stable. Scrotal ultrasound demonstrates a hypoechoic, heterogeneous mass with increased internal vascularity on color Doppler imaging. Laboratory studies show: Serum AFP: 285 ng/mL (normal <10 ng/mL)
Serum β-hCG: 1.2 mIU/mL (normal <1 mIU/mL)
Serum LDH: 420 U/L (normal <200 U/L) A radical inguinal orchiectomy is performed. Which of the following histologic findings would most likely account for the markedly elevated AFP with only minimally elevated β-hCG in this patient?
Answer choices
- AChoriocarcinoma
- BClassic seminoma
- CEmbryonal carcinoma with yolk sac tumor differentiationCorrect answer
- DMature cystic teratoma
- ESpermatocytic seminoma
- FPure non-seminomatous germ cell tumor of yolk sac origin
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