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Alpha-Fetoprotein Tumor Marker (Blood)

Does this test have other names?


What is this test?


AFP is normally made by a fetus's liver and yolk sac. It's the main protein during the first 3 months of development. AFP greatly decreases by age 1 and should only be found in adults in very low levels.

AFP is 1 of several tumor markers. Tumor markers are molecules in the blood that are higher when a person has certain cancers. AFP is found mainly in liver cancer and germ cell tumors of the testicles or ovaries, which are rare. These are found in the pineal gland in the brain.


Why do I need this test?

You may need this test if your healthcare provider thinks you may have liver cancer, testicular cancer, or cancers of the brain, mediastinum (chest), or blood.

This test is also used to track cancer treatment, or see if cancer has come back after treatment.  

What other tests might I have along with this test?

If your healthcare provider thinks you may have liver cancer, you may also have tests such as:


  • Blood clotting tests. Your liver makes proteins that help your blood clot. You may have blood tests, such as prothrombin time (PT) to find out how well your liver makes these proteins and to look at your risk of bleeding.


  • Complete blood count, or CBC. This test measures the level of your red blood cells, white blood cells, and platelets, which help blood to clot. It also shows how well your bone marrow is working. Your marrow is where new blood cells are made. 

  • Electrolytes and blood chemistry tests. Blood chemistry tests check the levels of certain substances in your blood, such as calcium, potassium, and glucose. For example, your blood calcium and cholesterol levels can rise when you have liver cancer, whereas your glucose level may fall.



  • Human chorionic gonadotropin (hCG)

  • Lactate dehydrogenase (LDH)

Your healthcare provider also is likely to order imaging tests, such as ultrasound, CT scan, or MRI, or a biopsy to check for different cancers. 

What do my test results mean?


AFP is measured in nanograms per milliliter (ng/mL). An AFP level between 10 ng/mL to 20 ng/mL is normal for adults. An extremely high level of AFP in your blood—greater than 400 ng/mL—could be a sign of liver tumors.



How is this test done?


Does this test pose any risks?


What might affect my test results?



How do I get ready for this test?

You don't need to prepare for this test. 

Online Medical Reviewer: Chad Haldeman-Englert MD
Online Medical Reviewer: Kenny Turley PA-C
Online Medical Reviewer: Maryann Foley RN BSN
Date Last Reviewed: 8/1/2020