Carcinoembryonic antigen (CEA)

Carcinoembryonic antigen (CEA) is a protein normally found in the tissue of a developing fetus. Levels of CEA in the blood decrease after birth. CEA is normally found in small amounts in the blood of most healthy people.

Why a CEA test is done

A CEA test may be done to:

• help diagnose and monitor a person’s response to treatment for certain cancers
  • It is most commonly used for colorectal cancer.
  • CEA may also be used for the following cancers:
    • breast
    • lung
    • pancreas
    • stomach
    • ovary
• check if a cancer has come back (recurred)

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How a CEA test is done

A CEA test is usually done in a private laboratory or hospital laboratory. No special preparation is usually needed.

• CEA is usually measured by a blood test.
• The sample is sent to a laboratory to be analyzed by special machines.

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What the results mean

An increased CEA value may be due to:

• smoking
  • Smokers who do not have cancer can have an increased CEA value.
• non-cancerous conditions
  • inflammatory bowel disease (such as colitis)
  • benign breast disease
  • benign ovarian disease
  • inflammation of the pancreas (pancreatitis)
  • liver disease (such as cirrhosis or hepatitis)
  • chronic lung disease
• cancerous conditions
  • colorectal cancer
  • breast cancer
  • lung cancer
  • pancreatic cancer
  • stomach cancer
  • ovarian cancer
  • bladder cancer
  • thyroid cancer
  • liver cancer

In cancerous conditions:

• A decrease in, or return to normal values of, CEA may mean that the cancer has responded well to treatment.
• An increase may mean that the cancer is not responding well to treatment, is still growing or is coming back (recurring).
  • A slight increase may not be significant. Usually the doctor looks at trends in the increase over time.

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What happens if a change or abnormality is found

The doctor will decide if more tests, procedures, follow-up care or additional treatment is needed.

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