A 28-year-old woman with a 7 cm right adnexal mass has serum AFP of 1800 ng/mL and β-hCG of 120 IU/L. CA-125 is normal. Intraoperatively, the tumor is unilateral with a yellow-grey cut surface and areas of hemorrhage. Which is the MOST likely diagnosis?

• A Dysgerminoma
• B Immature teratoma
• C Yolk sac tumor
• D Mixed germ cell tumor ✓

Explanation

Elevated AFP (characteristically yolk sac tumor) AND elevated β-hCG (characteristically choriocarcinoma component) together strongly suggest a mixed germ cell tumor. Pure yolk sac tumors secrete AFP but not β-hCG; pure dysgerminoma may have low β-hCG from syncytiotrophoblast cells but not elevated AFP. Mixed germ cell tumors contain two or more germ cell elements, which explains the combination of both markers.

Reference: Shaw's Textbook of Gynaecology, 17th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.