The CEA test is a blood test that measures the level of carcinoembryonic antigen (CEA), a protein that is produced in very low amounts by most healthy adults but may be elevated in certain cancers and non-cancerous conditions.

What the CEA test is used for

The CEA test is primarily used to:

• Monitor treatment for certain cancers.

• Assess how well cancer treatment is working.

• Check for cancer recurrence after treatment.

• Sometimes help evaluate a person with symptoms or imaging findings suggestive of cancer.

It is not recommended as a screening test for cancer in people without symptoms because many non-cancerous conditions can also raise CEA levels.

Cancers associated with elevated CEA

CEA may be elevated in:

• colorectal cancer (most commonly monitored)

• Pancreatic cancer

• Stomach (gastric) cancer

• Lung cancer

• Breast cancer

• Ovarian cancer

• Thyroid cancer (some types)

Non-cancer conditions that can raise CEA

CEA levels may also be elevated in:

• Smoking (smokers often have higher baseline CEA levels)

• Liver disease (such as hepatitis or cirrhosis)

• Pancreatitis

• Inflammatory bowel disease (such as Crohn's disease or ulcerative colitis)

• Lung diseases, including chronic obstructive pulmonary disease (COPD)

• Other inflammatory or infectious conditions

  Important note

  CEA is a tumor marker, but it cannot diagnose cancer on its own. Some people with cancer have normal CEA levels, while others without cancer may have elevated levels. Healthcare providers interpret CEA results along with your symptoms, medical history, imaging tests (such as CT or MRI), and, when necessary, biopsy results.

  Comparison with other tumor markers

  • AFP (Alpha-fetoprotein): Mainly associated with liver cancer and certain testicular or ovarian germ cell tumors.

  • CA 19-9: Primarily used to monitor pancreatic and biliary tract cancers.

  • CEA: Most commonly used to monitor colorectal cancer but may also be elevated in several other cancers and non-cancerous conditions.

  These markers are often ordered together when a healthcare provider is evaluating or monitoring cancer because each provides different information.