carcinoembryonic antigen (cea) test

test overview

the carcinoembryonic antigen (cea) test measures the amount of this protein that may appear in the blood of some people who have certain kinds of cancers, especially cancer of the large intestine (colon and rectal cancer). it may also be present in people with cancer of the pancreas, breast, ovary, or lung.

cea is normally produced during the development of a fetus. the production of cea stops before birth, and it usually is not present in the blood of healthy adults.

why it is done

the carcinoembryonic antigen (cea) test is used to monitor a person before and during treatment. along with other tests, this test may be used to see how well a treatment is working. and in some cases, it may be used with other tests to see if the cancer has grown or come back.

how to prepare

in general, there's nothing you have to do before this test, unless your doctor tells you to.

how it is done

• a health professional uses a needle to take a blood sample, usually from the arm.

watch

how it feels

when a blood sample is taken, you may feel nothing at all from the needle. or you might feel a quick sting or pinch.

risks

there is very little chance of having a problem from this test. when a blood sample is taken, a small bruise may form at the site.

results

results are usually available in 1 to 3 days.

normal

each lab has a different range for what's normal. your lab report should show the range that your lab uses for each test. the normal range is just a guide. your doctor will also look at your results based on your age, health, and other factors. a value that isn't in the normal range may still be normal for you.

most cancers do not produce this protein, so your cea may be normal even though you have cancer.

high values

many conditions can change your cea levels. your doctor will discuss any significant abnormal results with you in relation to your symptoms and medical history.

• cancer of the colon, lung, pancreas, breast, or ovary may be present.
• cancer may not be responding to treatment.
• cancer may have returned after treatment. a steadily rising cea may be the first sign that cancer has come back after treatment. also, people with advanced cancer or cancer that has spread to other parts of the body (metastatic cancer) may have high cea levels if their original cancer produced this protein before treatment.
• another condition or disease is present, such as cirrhosis, hepatitis, diverticulitis, inflammatory bowel disease, peptic ulcer disease, chronic obstructive pulmonary disease (copd), inflammation of the gallbladder (cholecystitis), or an obstructed bile duct.