What are the other Names for this Test? (Equivalent Terms)
- CEA Test
What is Carcinoembryonic Antigen (CEA) Test? (Background Information)
- A Carcinoembryonic Antigen (CEA) Test is a tumor marker test that measures the amount of a protein called Carcinoembryonic Antigen (CEA), in blood. In individuals who have specific types of cancers affecting the colon, rectum, pancreas, or lung; CEA levels are markedly high
- CEA is a type of protein normally produced by the tissues of a developing fetus. The protein production stops (or significantly slows down) before birth and is normally not present (or present in very low amounts) in the blood of healthy adults
- In adults, detection of elevated levels of CEA in blood may indicate cancer of the large intestine (colon, rectum). Other cancers in which CEA may be elevated include cancers of the pancreas, lung, breast, liver, stomach, ovary, and medullary thyroid
- It has to be noted that CEA levels may also be increased during other noncancerous conditions, such as inflammatory bowel disease, peptic ulcer, cirrhosis, hepatitis, chronic obstructive pulmonary disease, obstruction of the bile duct, lung infection, cholecystitis, and pancreatitis. Hence for this reason, the test is not routinely used for screening cancer among the general population
- However, CEA test is used in assessing the growth of cancer, or evaluating the response of cancer to treatment, in cases where the levels are positive in individuals diagnosed with cancer
What are the Clinical Indications for performing the Carcinoembryonic Antigen (CEA) Test?
- The CEA test may be prescribed to patients to evaluate the success of treatment, and to determine if cancer has returned after treatment (relapse or recurrent cancer). The test is ordered at the start of cancer therapy (to determine baseline CEA levels) and then performed at regular intervals
- CEA test may also be ordered by the healthcare provider to evaluate the growth and severity of the cancer. In such cases, the healthcare provider may even order the analysis of body fluids such as peritoneal, pleural, and cerebrospinal fluid to establish CEA levels and thus determine the growth or spread of the tumor
How is the Specimen Collected for Carcinoembryonic Antigen (CEA) Test?
Sample required: Blood or body fluids (such as peritoneal, pleural, or cerebrospinal fluid)
Process: Insertion of needle into a vein (arm) for blood. Other body fluids are collected by insertion of needle into the respective body spaces
Preparation required: None
What is the Significance of the Carcinoembryonic Antigen (CEA) Test Result?
- The normal or reference value range for CEA varies for different laboratories. The healthcare provider interprets the result based on lab reference values and other patient factors that may influence the result
- A test that is negative or normal for CEA does not signify the absence of cancer, because not all cancers are CEA positive. In other words, cancers that do not produce CEA, will show a negative test result
- For cancer types having elevated or positive CEA levels, the test is used as an important tool for evaluating the patient’s response to treatment. Decreasing levels of CEA signifies a positive response to treatment. The return of CEA to normal levels, after start of treatment denotes a successful treatment
- If CEA levels start increasing after the cancer has been successfully treated; it usually indicates recurrence of the tumor
- Greater the elevation in CEA levels, larger is the tumor size, or greater is its spread throughout the body. Also, if CEA levels are found elevated in other body fluids, it usually signifies that the cancer has spread to that particular region of the body
The laboratory test results are NOT to be interpreted as results of a "stand-alone" test. The test results have to be interpreted after correlating with suitable clinical findings and additional supplemental tests/information. Your healthcare providers will explain the meaning of your tests results, based on the overall clinical scenario.
Additional and Relevant Useful Information:
- CEA levels are generally found to be higher in smokers, than non-smokers
Certain medications that you may be currently taking may influence the outcome of the test. Hence, it is important to inform your healthcare provider, the complete list of medications (including any herbal supplements) you are currently taking. This will help the healthcare provider interpret your test results more accurately and avoid unnecessary chances of a misdiagnosis.