A 67-year-old woman with known ovarian serous carcinoma has serum CA-125 levels measured serially. Which statement best describes the utility of CA-125 in this context?

• A CA-125 is specific for ovarian cancer and is used for primary screening
• B A normal CA-125 reliably excludes ovarian carcinoma
• C CA-125 is encoded by MUC16 and is elevated only in malignant conditions
• D CA-125 is best used to monitor response to therapy and detect recurrence ✓

Explanation

CA-125 (encoded by MUC16) is the most useful tumor marker for monitoring treatment response and detecting recurrence in ovarian serous carcinoma; it is not specific enough for primary population screening. CA-125 can be elevated in benign conditions such as endometriosis, pelvic inflammatory disease, and early pregnancy, limiting its specificity. Serial measurements trending upward after treatment suggest relapse rather than a single absolute value.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.