CA 19-9 Test

CA 19-9 is used as a tumour marker: 

• to help tell the difference between cancer of the pancreas and bile ducts and other non-cancerous conditions, such as pancreatitis; 
• to monitor a patient's response to pancreatic cancer treatment; and
• to watch for pancreatic cancer recurrence.

CA 19-9 may be requested along with other tests, such as carcinoembryonic antigen (CEA), bilirubin, and/or liver function tests, when a patient has symptoms that may indicate pancreatic cancer, including abdominal pain, nausea, weight loss, and jaundice.

If CA 19-9 is initially elevated in pancreatic cancer, then it may be requested several times during cancer treatment to monitor response and, on a regular basis following treatment, to help detect recurrence of the cancer.

Small increases in CA 19-9 levels can be detected in some healthy people, and in many benign conditions that affect the liver or pancreas can cause a temporary rise in CA 19-9.

Moderate to high levels are found in pancreatic cancer, other cancers, and in several other diseases and conditions. The highest levels of CA 19-9 are seen in a condition called excretory ductal pancreatic cancer - cancer that is found in the pancreas tissues that produce food-digesting enzymes and in the ducts that carry those enzymes into the small intestine. This tissue is where 95% of pancreatic cancers are found.

Repeated measurements of CA 19-9 may be useful during and following treatment because rising or falling levels may give your doctor important information about whether the treatment is working, whether all of the cancer was removed successfully during surgery, and whether the cancer is returning.

Unfortunately, early pancreatic cancer gives few warnings. By the time a patient has symptoms and elevated levels of CA 19-9, their pancreatic cancer is usually at an advanced stage.