A CEA blood test measures the level of carcinoembryonic antigen (CEA) in a person’s blood. CEA is a protein that is normally produced during fetal development, but is not usually found in the blood of healthy adults. However, CEA levels may become elevated in certain medical conditions, particularly certain types of cancer.

The CEA blood test is typically ordered to help monitor the progression of certain types of cancer, particularly colorectal cancer. It may also be used to monitor the response to cancer treatment or to detect the recurrence of cancer after treatment.

During the test, a small sample of blood is taken from a vein in the arm and sent to a laboratory for analysis. The normal range for CEA levels in the blood varies depending on the laboratory, but generally falls below 5 nanograms per milliliter (ng/mL).

Elevated CEA levels may indicate the presence of certain types of cancer, particularly colorectal cancer. However, CEA levels can also become elevated in non-cancerous conditions, such as inflammatory bowel disease or certain infections. Therefore, a high CEA level does not necessarily mean that a person has cancer.

In addition to monitoring the progression of cancer, the CEA blood test may also be used to help diagnose certain types of cancer. However, it is not a definitive diagnostic test and further testing, such as a biopsy, may be necessary to confirm a cancer diagnosis.

It is important to note that the CEA blood test is only one component of a comprehensive evaluation for cancer and should not be used as a sole diagnostic tool. A healthcare provider can interpret the results of a CEA blood test in the context of the individual’s medical history and other test results, and develop an appropriate treatment plan if necessary.