CA 19-9
What this test measures
CA 19-9 is a sugar-protein made by cells lining the pancreas, bile ducts and gut. Tumour markers are proteins that can rise for many reasons, most of them not cancer. Specialists mainly use them to follow a condition that has already been identified, and a single value cannot answer a screening question on its own.
Why doctors request it
Specialists use it to follow pancreatic and bile duct conditions. About one person in ten cannot make it at all, so a low value is not always informative.
What commonly pushes it up
- Blocked bile ducts and gallstones
- Pancreatitis and liver disease
- Diabetes, slightly
- Lung and thyroid conditions
- Pancreatic and bile duct cancers
What commonly pushes it down
- People with the Lewis-negative blood group make none, whatever their health
Everyday reasons for a value outside the range
- A blocked bile duct alone can raise it into the thousands
- Benign pancreatitis raises it
About the sample
No fasting needed.
Upload a photo or PDF and see every line against the range your lab printed, explained in plain English. First report free.
Read my report freeThis is an educational summary of results you uploaded. It is not medical advice, a diagnosis or a treatment plan, and it does not replace the doctor who requested the test. If you are worried, or a result is marked outside range, discuss it with your doctor. Written and reviewed by a UK consultant physician. Reference ranges vary between laboratories.