From the Guidelines
CA 19-9 is not a sensitive marker for ovarian cancer, and its use is limited to distinguishing primary mucinous ovarian tumors from gastrointestinal metastasis. The most recent and highest quality study, published in 2023 in the Annals of Oncology 1, suggests that CA 19-9 is only elevated in approximately 50% of International Federation of Gynecology and Obstetrics (FIGO) stage I cases, and its elevation is not specific to ovarian cancer.
Key Points to Consider
- CA 125 is the more commonly used tumor marker for ovarian cancer, but it also has limitations in sensitivity and specificity, particularly in early-stage disease 1.
- Measuring serum carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 levels in addition to CA-125 may help distinguish primary mucinous ovarian tumors from a gastrointestinal metastasis 1.
- Initial imaging should comprise pelvic ultrasound and computed tomography (CT) of the thorax, abdomen, and pelvis to complete clinical staging and aid surgical planning 1.
- A definitive diagnosis of ovarian cancer requires pathological examination by an expert pathologist of tumor samples from either a diagnostic biopsy or a surgical specimen 1.
Clinical Implications
- The use of CA 19-9 as a tumor marker for ovarian cancer is not recommended due to its limited sensitivity and specificity.
- A combination of transvaginal ultrasound, physical examination, and appropriate tumor marker testing based on clinical suspicion is the most effective approach for ovarian cancer detection.
- CA 19-9 may be useful in distinguishing primary mucinous ovarian tumors from gastrointestinal metastasis, but its use should be limited to this specific context.
From the Research
CA 19-9 Sensitivity for Ovarian Cancer
- The sensitivity of CA 19-9 for ovarian cancer has been investigated in several studies 2, 3, 4.
- A study published in 2022 found that the sensitivity of CA 19-9 for ovarian cancer was 96.19% 2.
- Another study published in 2016 found that CA 19-9 had a sensitivity of 66.7% for mucinous ovarian cancer when used alone, but this increased to 95.1% specificity and 66.7% sensitivity when combined with CA 125 3.
- A more recent study published in 2023 found that CA 19-9 combined with HE4 had a sensitivity of 72.73% and specificity of 78.41% for diagnosing endometriosis-associated ovarian cancer 4.
Comparison with Other Biomarkers
- CA 19-9 has been compared with other biomarkers such as CA 125 and miRNA-204 in terms of sensitivity and specificity for ovarian cancer 2.
- The study found that the combination of CA 19-9, CA 125, and miRNA-204 had a high sensitivity and specificity for ovarian cancer, with an area under the receiver operating characteristic curve of 0.938,1.000, and 0.998 for benign tumors and early and late ovarian carcinomas, respectively 2.
Clinical Applications
- The studies suggest that CA 19-9 may be a useful biomarker for the diagnosis of ovarian cancer, particularly when combined with other biomarkers such as CA 125 and HE4 2, 3, 4.
- However, the sensitivity and specificity of CA 19-9 for ovarian cancer can vary depending on the specific type of ovarian cancer and the population being studied 2, 3, 4.