Elevated serum AFP with low free β-hCG in an adult male with a testicular mass most strongly suggests which histological type?
- A Pure seminoma
- B Pure choriocarcinoma
- C Yolk sac tumor (endodermal sinus tumor) ✓
- D Mature teratoma
Correct answer: C. Yolk sac tumor (endodermal sinus tumor)
Explanation
AFP is produced by yolk sac (endodermal sinus) elements; pure yolk sac tumors markedly elevate serum AFP. Pure seminomas do not produce AFP (though they may mildly raise hCG via syncytiotrophoblastic giant cells). Choriocarcinoma markedly elevates β-hCG, not AFP. Mature teratoma does not typically produce serum markers.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.