Alpha-fetoprotein (AFP) tumor marker test
Reviewed
Also called: AFP tumor marker test, total AFP, alpha-fetoprotein-L3 percent
An AFP tumor marker test is a blood test that measures the level of AFP (alpha-fetoprotein) in a sample of your blood.
Specimen: Blood
Why this test may be ordered
- To monitor certain types of cancer and cancer treatment
- To help make a prognosis
- To check whether cancer has returned after treatment
- To monitor chronic liver diseases (cirrhosis, chronic hepatitis B or C) along with liver ultrasound every six months to help detect liver cancer early
Preparation and collection
You don't need any special preparations for an AFP tumor marker test.
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.
Understanding results
Because high levels of AFP don't always mean cancer, health care providers don't use the results from an AFP test alone to screen for or diagnose cancer.
- High AFP level: High levels of AFP may be a sign of cancer of the liver, ovaries, or testicles. Limitation: However, high levels could also be a sign of liver injury and liver diseases that aren't cancer. Next step: Your provider will use your medical history and other test results to make a diagnosis.
- Normal AFP level: Normal levels of AFP mean you're less likely to have a cancer that causes high AFP levels. Limitation: But a normal test result doesn't rule out cancer because some people with these cancers have normal AFP levels. Next step: Ask your provider to explain what your test results mean for your health.
- AFP levels increasing during cancer treatment: Your AFP levels are increasing, it may mean that your treatment isn't working. Limitation: If you're being treated for a cancer that increased your AFP levels, you may be tested several times during treatment. Next step: Your provider will look at all your AFP test results to see how your levels have changed over time.
- AFP levels decreasing during cancer treatment: Your AFP levels are decreasing, it may mean your treatment is working. Limitation: AFP levels often go up as tumors grow and go down as they shrink. Next step: Your provider will look at all your AFP test results to see how your levels have changed over time.
- AFP levels stayed the same during cancer treatment: Your AFP levels have stayed the same, it may mean your disease is stable and hasn't gotten better or worse. Limitation: AFP levels often go up as tumors grow and go down as they shrink. Next step: Your provider will look at all your AFP test results to see how your levels have changed over time.
- AFP not normal after finishing treatment: Not normal, it may mean that you still have some cancer in your body. Limitation: However, some people who have liver, ovarian, or testicular cancer can have normal AFP levels. Next step: Ask your provider to explain what your test results mean for your health.
- Sudden increase or very high AFP with chronic liver disease: A very high level of AFP or a sudden increase can be an early sign of liver cancer. Limitation: However, high levels could also be a sign of liver injury and liver diseases that aren't cancer. Next step: If you have a long-lasting liver disease that's not cancer, you may need other tests to check for liver cancer if your test results show a sudden increase in AFP or your level is very high.
- High AFP levels may also be caused by noncancerous conditions such as cirrhosis, chronic hepatitis B or C, or liver disease.
- Some people with liver, ovarian, or testicular cancer can have normal AFP levels.
- This test alone cannot be used to screen for or diagnose cancer.
What to do next
Ask your provider to explain what your test results mean for your health.
- Why are you ordering an AFP test for me?
- Could a noncancerous liver condition explain my result?
- What other tests will I need along with this one?
- How often will my AFP level be checked?
Evidence source
Source: U.S. National Library of Medicine (MedlinePlus). Practices and reference ranges may differ in your country.
U.S. National Library of Medicine: Alpha-fetoprotein (AFP) tumor marker test