Blood tumor marker used to monitor treatment response and recurrence in pancreatic and biliary tract cancers. Not used for screening.
Indication
- Monitoring treatment response in diagnosed pancreatic cancer
- Follow-up of biliary tract cancer (cholangiocarcinoma)
- Monitoring recurrence after surgery
- Assessment of treatment efficacy during chemotherapy
- Supportive test in differential diagnosis of pancreatic mass (together with clinical findings)
- Routine follow-up in patients responding to treatment
Preparation
- Special fasting is not required; however, 8-12 hours of fasting may be advised when ordered with combined tests
- Current medications and history of jaundice should be reported
- Bringing previous tumor marker results
How it's performed
- A venous blood sample is drawn from the arm
- Serum is separated and measurement is performed by immunological method
- Result is reported in U/mL; threshold values vary by laboratory
- Interpretation is performed together with clinical findings and imaging
Post-procedure
- Repeat measurement at defined intervals during the treatment process
- Rising values are evaluated with imaging
- Results are discussed in person with the physician
- Awareness that values may be falsely elevated in jaundice (biliary obstruction)
Risks
- Minor bruising or tenderness related to blood draw
- False elevation in benign conditions such as jaundice, pancreatitis, and cholangitis
- In Lewis antigen-negative individuals (~5-10%), test results may be unreliable
- Use as a screening test may lead to erroneous results
FAQ
If CA 19-9 is high, does it definitely mean cancer?
No. It can also rise in benign conditions such as pancreatitis, jaundice, cholangitis, and liver diseases. It does not establish a diagnosis on its own.
Can I have it done for pancreatic cancer screening?
CA 19-9 is not recommended as a screening test. It is used only in patients with a confirmed diagnosis for treatment monitoring and recurrence follow-up.
When are the results available?
Most laboratories provide results the same day or within 1 business day.
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