CA 19-9 Blood Test

About the test

CA 19-9 is a biomarker that is commonly used in the diagnosis and management of certain medical conditions, mainly pancreatic and gastrointestinal cancers. It is an antigen known as cancer antigen 19-9, which is present in elevated levels in the blood of some individuals with these types of cancer.

While it is most frequently associated with pancreatic and gastrointestinal cancers, elevated levels of CA 19-9 can also be found in other conditions, such as liver disease, gallbladder disease, and certain other benign gastrointestinal conditions. Therefore, it is crucial to interpret CA 19-9 results in conjunction with other diagnostic tests, physical examination finding and symptoms to ensure accurate diagnosis and appropriate management.

A raised CA 19-9 does not necessarily mean that you have cancer but should definitely prompt further investigations to rule this out. Although CA 19-9 testing provides valuable information, it is important to note that it has limitations. CA 19-9 levels can be elevated in non-cancerous conditions, and some individuals with pancreatic or gastrointestinal cancers may have normal CA 19-9 levels – a ‘false negative’. So, even if the result is normal, you should seek medical attention if you are losing weight unexpectedly, have yellowing of the skin or eyes, have dark urine or pale stools, or have unexplained back or abdominal pain.

1 Biomarker