A 55-year-old woman has a 14 cm multiloculated right ovarian mass. Serum CA-125 is 24 U/mL (normal range), but CA 19-9 is 940 U/mL and CEA is 22 ng/mL. Frozen section confirms mucinous ovarian carcinoma. Which statement best explains this marker profile?

• A CEA elevation indicates the tumour is a dysgerminoma variant
• B Low CA-125 excludes malignancy in any ovarian mass
• C Elevated CA 19-9 proves the tumour is pancreatic in origin
• D CA-125 is falsely low in mucinous tumours, so CA 19-9 and CEA are more useful markers ✓

Explanation

Mucinous epithelial ovarian cancers express CA 19-9 and CEA far more consistently than CA-125, so a normal CA-125 does not exclude malignancy when the histotype is mucinous. This is why Indian textbook practice recommends adding CA 19-9 and CEA whenever a mucinous ovarian tumour is suspected. Option C is wrong because CA 19-9 is also produced by mucinous ovarian primaries.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.