Also Known As
Formal Name
Carcinoembryonic Antigen
This article was last reviewed on
This article waslast modified on 2 November 2020.
At a Glance
Why Get Tested?

In the presence of certain cancers, CEA may be used to monitor the effect of treatment and recurrence of disease

When To Get Tested?

Before starting cancer treatment as well as at intervals during and after therapy

Sample Required?

A blood sample taken from a vein in the arm

Test Preparation Needed?

No test preparation is needed

On average it takes 7 working days for the blood test results to come back from the hospital, depending on the exact tests requested. Some specialist test results may take longer, if samples have to be sent to a reference (specialist) laboratory. The X-ray & scan results may take longer. If you are registered to use the online services of your local practice, you may be able to access your results online. Your GP practice will be able to provide specific details.

If the doctor wants to see you about the result(s), you will be offered an appointment. If you are concerned about your test results, you will need to arrange an appointment with your doctor so that all relevant information including age, ethnicity, health history, signs and symptoms, laboratory and other procedures (radiology, endoscopy, etc.), can be considered.

Lab Tests Online-UK is an educational website designed to provide patients and carers with information on laboratory tests used in medical care. We are not a laboratory and are unable to comment on an individual's health and treatment.

Reference ranges are dependent on many factors, including patient age, sex, sample population, and test method, and numeric test results can have different meanings in different laboratories.

For these reasons, you will not find reference ranges for the majority of tests described on this web site. The lab report containing your test results should include the relevant reference range for your test(s). Please consult your doctor or the laboratory that performed the test(s) to obtain the reference range if you do not have the lab report.

For more information on reference ranges, please read Reference Ranges and What They Mean.

What is being tested?

CEA is a protein that is normally not detected in the blood of a healthy person. When certain types of cancer are present, CEA may be produced by the cancer cells. CEA may then be detected in blood, but it will not indicate which kind of cancer is present. CEA is often used to monitor patients with cancers of the gastrointestinal (GI) tract such as bowel (colorectal) cancer. It may be raised in other cancers, such as ovarian and breast cancers, but can also be raised in benign conditions such as liver disease and inflammatory bowel disease (Crohns disease or ulcerative colitis).

Accordion Title
Common Questions
  • How is it used?

    CEA is most useful to monitor treatment of cancer patients. It is used for patients who have had surgery, to measure response to therapy and to monitor whether the disease has recurred. In 2011, NICE (National Institute for Health and Care Excellence) published guidelines for the diagnosis and management of bowel cancer (CG131) that are currently referred to by the British Society of Gastroenterology. Their recommendations are that bowel surgery is followed up with regular CEA blood testing (at least every 6 months in the first 3 years). A blood test for CEA in this circumstance is used as a tumour marker, i.e. an indicator of whether the cancer is present or not.

    CEA is used as a marker for bowel cancer in particular, but may be measured where other forms of cancer are present. It has been found helpful in monitoring some patients with cancer of the rectum, lung, breast, liver, pancreas, stomach, and ovary. Not all cancers produce CEA, and a level within the given reference range does not guarantee that cancer (even the kinds known to produce CEA) is not present, therefore the CEA test is not used for screening the general population.

  • When is it requested?

    A CEA test may be requested when the patient's symptoms suggest the possibility of cancer. CEA is most useful however, when measured in patients with cancers known to produce the protein before and during or after treatment. It is also used to follow up patients after treatment.

  • What does the test result mean?

    The concentration of CEA in the blood does not accurately reflect tumour size, however on initial testing, patients with smaller and early-stage tumours are likely to have low, if not normal, CEA concentrations, while patients with more advanced tumours, or tumours that have spread throughout the body, are likely to have initially high CEA concentrations. When CEA decreases to "normal" concentrations after therapy, it means that the CEA-producing tumour has been removed. A steadily rising CEA result may be the first sign that the cancer has returned.

  • Is there anything else I should know?

    CEA is a protein that is found in developing tissues of babies. By the time a baby is born, detectable levels in the blood disappear.
    Increased CEA concentrations can indicate some non-cancer-related conditions, such as liver disease, and inflammatory bowel disease. Also, smokers tend to have higher concentrations in the blood than non-smokers.

  • If my CEA results rise and indicate cancer, what are my treatment options?

    Treatment may include surgery, chemotherapy, or radiation, or a combination of them.

  • If I am a smoker, does an elevated CEA result mean I have cancer?

    Not necessarily. Smokers can have a higher “normal” range than non-smokers and not have cancer.