A 45-year-old woman has a serum AFP level of 2800 ng/mL with a hepatic mass. Which feature of AFP in the context of tumor markers is most accurately described?

• A It is specific for hepatocellular carcinoma and not elevated in germ cell tumors
• B It is produced exclusively by Sertoli cells in testicular tumors
• C Elevation above 400 ng/mL is pathognomonic for hepatocellular carcinoma
• D It is encoded by the same gene as albumin and expressed by fetal hepatocytes ✓

Explanation

Alpha-fetoprotein (AFP) is a fetal plasma protein encoded by the same gene cluster as albumin, normally produced by fetal yolk sac and hepatocytes; its expression is markedly downregulated after birth. Elevated AFP occurs in HCC and also in non-seminomatous germ cell tumors (yolk sac tumors), so it is not HCC-specific. Thresholds correlate with HCC risk but are not pathognomonic, as AFP can be raised in cirrhosis and other conditions.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.