CA 19 9 Carbohydrate Antigen

Category:

CA-19-9 (Carbohydrate Antigen)

Description

CA 19-9 is often produced by pancreatic cancers, and its level is elevated in more than 90% of pancreatic cancers. It's typically used to gauge how well a treatment is working in those diagnosed with pancreatic cancer.

CA 19-9 may be ordered along with other tests, such as carcinoembryonic antigen (CEA), bilirubin, and/or a liver panel, 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 ordered during cancer treatment to monitor response and, on a regular basis following treatment, to help detect recurrence.

Its concentration is measured by means of analysis of a blood sample drawn from the vein in the arm.

Purpose of the test

Once the diagnosis of pancreatic cancer is confirmed, routine blood studies are performed to assess liver and kidney function.

Checking the CA 19-9 levels can be a useful gauge of how the treatment is working. After treatment, the doctor may check the CA 19-9 levels regularly as one indicator of whether the cancer has returned.

However, CA 19-9 is not an absolute test for pancreatic cancers, and other conditions may cause a rise in the CA 19-9 levels. Likewise, a normal CA 19-9 level is not a guarantee that the cancer has not returned.

Its main use is as a tumor marker:
- to help differentiate between cancer of the pancreas and bile ducts and other conditions, such as pancreatitis
- to monitor a patient's response to pancreatic cancer treatment
- to watch for pancreatic cancer recurrence.

Reference range values
0-37 U/mL

Abnormal findings

Moderate to high levels of CA-19-9 are found in pancreatic cancer, other cancers, and in several other diseases and conditions. The highest levels of CA 19-9 are seen in excretory ductal pancreatic cancer.

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

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