A 45-year-old woman has a right ovarian cyst with a CA-125 of 420 U/mL, a solid component on ultrasound, and elevated LDH. Which serum marker is MOST specific for dysgerminoma among the following?
- A LDH (lactate dehydrogenase) ✓
- B CA-125
- C AFP (alpha-fetoprotein)
- D β-hCG
Correct answer: A. LDH (lactate dehydrogenase)
Explanation
Dysgerminoma is the most common malignant germ cell tumor and characteristically secretes LDH, particularly LDH-1 isoform. AFP is elevated in yolk sac (endodermal sinus) tumors. β-hCG is elevated in non-gestational choriocarcinoma and mixed germ cell tumors. CA-125 is elevated in epithelial ovarian cancers (especially serous). LDH elevation is the hallmark biochemical marker for dysgerminoma.
Reference: Shaw's Textbook of Gynaecology, 17th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.