At a Glance
Why Get Tested?
Primarily to monitor cancer treatment, including response to therapy and recurrence; as an indicator of the amount of cancer or size of tumor present (tumor burden) and to assist in determining prognosis and cancer staging; to determine if cancer has spread (metastasis); occasionally as follow up to a positive screening test for cancer, to help determine whether cancer is present in the body, though it is not useful as a general population screening test
When to Get Tested?
When you have been diagnosed with colon, pancreas, breast, lung, ovarian, medullary thyroid or other cancer prior to starting cancer treatment and then, if elevated, at intervals during and after therapy; occasionally when cancer is suspected but not confirmed – to aid in its detection
Test Preparation Needed?
The Test Sample
What is being tested?
Carcinoembryonic antigen (CEA) is a protein that is present in certain tissues of a developing baby (fetus). By the time a baby is born, it drops to a very low level. In adults, CEA is normally present at very low concentrations in blood but may be elevated in certain types of cancer. This test measures the amount of CEA in the blood to help evaluate individuals diagnosed with cancer.
CEA is a tumor marker. Originally, it was thought that CEA was a specific marker for colon cancer, but further study has shown that an increase in CEA may be seen in a wide variety of other cancers. CEA can also be increased in some non-cancer-related conditions, such as inflammation, cirrhosis, peptic ulcer, ulcerative colitis, rectal polyps, emphysema, and benign breast disease, and in smokers. For this reason, it is not useful as a general cancer screening tool, but it does have a role in evaluating response to cancer treatment and in cancer surveillance. When an individual has been diagnosed with cancer, an initial baseline test for CEA may be performed. If this level is elevated, then subsequent serial testing of CEA may be performed to monitor the cancer as the individual undergoes treatment.
How is the sample collected for testing?
NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.
Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.
Is any test preparation needed to ensure the quality of the sample?
No test preparation is needed.
Ask a Laboratory Scientist
NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used.
Sources Used in Current Review
(Revised 2012 January 20). How is Thyroid Cancer Diagnosed? American Cancer Society [On-line information]. Available online at http://www.cancer.org/Cancer/ThyroidCancer/DetailedGuide/thyroid-cancer-diagnosis through http://www.cancer.org. Accessed October 2012.
Dugdale, D. (Updated 2011 August 5). CEA blood test. MedlinePlus Medical Encyclopedia. [On-line information]. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003574.htm. Accessed October 2012.
(Revised 2012 October 1). How is colorectal cancer diagnosed? American Cancer Society. [On-line information]. Available online at http://www.cancer.org/Cancer/ColonandRectumCancer/DetailedGuide/colorectal-cancer-diagnosed through http://www.cancer.org. Accessed October 2012.
(© 1995-2012). Carcinoembryonic Antigen (CEA), Serum. Mayo Clinic Mayo Medical Laboratories [On-line information]. Available online at http://www.mayomedicallaboratories.com/test-catalog/Overview/8521 through http://www.mayomedicallaboratories.com. Accessed October 2012.
(Revised 2011 March 24). Common cancers and the tumor markers linked to them. American Cancer Society [On-line information]. Available online through http://www.cancer.org. Accessed October 2012.
(Reviewed 2011 December 30). Tests to Detect Colorectal Cancer and Polyps. National Cancer Institute. [On-line information]. Available online at http://www.cancer.gov/cancertopics/factsheet/detection/colorectal-screening through http://www.cancer.gov. Accessed October 2012.
Pagana, K. D. & Pagana, T. J. (© 2011). Mosby's Diagnostic and Laboratory Test Reference 10th Edition: Mosby, Inc., Saint Louis, MO. Pp 223-224.
Clarke, W., Editor (© 2011). Contemporary Practice in Clinical Chemistry 2nd Edition: AACC Press, Washington, DC. Pp 244-245.
Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. Burtis CA, Ashwood ER, Bruns DE, eds. 4th edition, St. Louis: Elsevier Saunders; 2006, Pg 768.
Sources Used in Previous Reviews
Clarke, W. and Dufour, D. R., Editors (2006). Contemporary Practice in Clinical Chemistry, AACC Press, Washington, DC. Pp 244-245.
Pagana K, Pagana T. Mosby's Manual of Diagnostic and Laboratory Tests. 3rd Edition, St. Louis: Mosby Elsevier; 2006 pp 161-162.
MedlinePlus Medical Encyclopedia: CEA. Available online at http://www.nlm.nih.gov/medlineplus/ency/article/003574.htm. Accessed February 2009.