Carcino Embryonic Antigen (CEA) is a protein that is present in the blood of some individuals with certain types of cancer, including colon, lung, and breast cancer. The CEA test measures the level of CEA in the blood, and can be used to monitor the progression of these cancers and the effectiveness of treatment.

Pre-test preparation for CEA typically involves fasting for 8-12 hours prior to the test, as well as avoiding certain medications that can affect the results.

The CEA test is typically performed using a blood sample, which is analyzed in a lab. The results of the test are reported as a numerical value, which can be compared to a reference range to determine whether the level of CEA is elevated.

Some common symptoms that may lead a doctor to prescribe a CEA test include weight loss, fatigue, abdominal pain, and blood in the stool. However, CEA can be elevated in individuals without symptoms, so it is not always a reliable marker of cancer.

If the CEA test results are elevated, further testing and diagnostic procedures may be necessary to determine the cause and make a diagnosis.

Reference range for CEA is generally considered to be less than 2.5 ng/ml, but this can vary depending on the laboratory and other factors. Elevated levels of CEA can indicate cancer, but it is not specific to any one type of cancer.

It’s important to note that CEA is not a diagnostic test, but a tumor marker test. Elevated CEA can be seen in other disease conditions other than cancer, such as lung and liver disease, smoking and also in some normal individuals. Therefore it should be used in conjunction with other diagnostic tests and imaging. A positive CEA result should not be used to diagnose cancer, but instead should prompt further testing and evaluation.