The short answer
AFP (alpha-fetoprotein) is a protein measured in blood. It is used as a tumor marker for some liver cancers and germ cell tumors, such as some testicular and ovarian cancers. Liver conditions such as cirrhosis and hepatitis can also raise it, so your care team reads it with other results.
AFP (alpha-fetoprotein) is a protein measured with a blood test.
It is used with some liver cancers and germ cell tumors, including some testicular and ovarian cancers.
Non-cancer liver conditions, such as cirrhosis and hepatitis B or C, can raise AFP.
Some people with these cancers have normal AFP levels.
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The short version
AFP stands for alpha-fetoprotein. It is a protein made by the liver. Levels are normally high in an unborn baby and drop very low after birth, so most healthy adults who are not pregnant have very little. AFP is used as a tumor marker: a substance measured in blood that can run higher in some cancers. It is not a simple yes-or-no cancer test.
What AFP is used for
The National Cancer Institute lists AFP as a marker for liver cancer, ovarian cancer, and germ cell tumors (tumors that start in the cells that become eggs or sperm, such as some testicular tumors). MedlinePlus names liver cancer, germ cell tumors of the ovaries, and nonseminomatous germ cell tumors of the testicles. Care teams may use it to:
- Help with diagnosis, together with imaging and other tests.
- Follow how well treatment is working. AFP levels often go up as these tumors grow and down as they shrink.
- Watch for cancer coming back after treatment (NCI notes markers are also measured after treatment ends).
Why it is not read alone
The National Cancer Institute notes two limits that apply to tumor markers in general. Noncancerous conditions can sometimes raise a marker. And not everyone with a given cancer has a higher level of its marker. So one number is easy to misread. Care teams read it together with imaging, exams, and other results. When a marker is checked again and again during treatment, the pattern over time can help show whether treatment is working.
For AFP in particular, MedlinePlus notes that liver conditions such as cirrhosis (scarring of the liver) and chronic hepatitis B or C can raise it. It also notes that some people with these cancers have normal AFP levels.
Normal ranges vary by lab
Your report lists a reference range, the range that lab calls normal. Labs often use different testing methods, so they often use different ranges. That means results from different labs can't always be compared directly. Your care team knows which lab ran your test and how to read your result.
What to ask
Ask why your care team is measuring AFP. Ask what your level and its trend suggest. Ask whether a liver condition or other cause could explain a change, and how the result fits with your imaging. Their reading of your full picture is what applies to you.
Sources
Common questions
Does a high AFP mean I have cancer?
Not by itself. MedlinePlus notes that high AFP levels don't always mean cancer. Liver conditions such as cirrhosis and chronic hepatitis B or C can raise it. More tests are needed, and your care team reads AFP with imaging and other results.
What is AFP used for in cancer care?
The National Cancer Institute lists AFP as a marker for liver cancer, ovarian cancer, and germ cell tumors. It can help with diagnosis and with following how treatment is working. MedlinePlus notes that AFP levels often go up as these tumors grow and down as they shrink.
Can AFP be normal even if there is cancer?
Yes. MedlinePlus notes that some people with these cancers have normal AFP levels. That is one reason AFP is not used alone.
Do I need to prepare for an AFP test?
MedlinePlus says no special preparation is needed for an AFP tumor marker test. Ask your care team if they have other instructions for you.
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Sources last checked: 2026-10-02 what this meansLast updated: 2026-10-02Next planned review: 2027-09-27
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Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes, and this is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Source checked — This page was written with AI assistance and then compared with the sources listed on it, looking for statements those sources do not back up. That check is not a sentence-by-sentence record and can miss errors. It is not a medical review, and it does not confirm the page is complete or right for your situation.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
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