Alpha-fetoprotein (AFP): what it is, what it tells you and when it’s tested

Alpha-fetoprotein, or AFP, is a protein a baby makes in large amounts before birth. After birth it falls to very low levels. In adults it can rise again when the liver is inflamed or repairing itself, for example with hepatitis or cirrhosis, and with some cancers of the liver, testicles or ovaries. It is not used to look for cancer in people who feel well.

When it’s tested

Doctors mostly order it in three cases. In people with cirrhosis or chronic hepatitis, sometimes alongside ultrasound at regular liver check-ups. In people with liver cancer, to follow treatment. And in germ cell tumours, of the testicle or ovary, where it helps diagnosis and check-ups.

It is not a screening test for people who feel well. Even for people with cirrhosis, guidelines put ultrasound first: AFP alone misses many small tumours, and it often rises without any tumour.

That is why Rosa does not test it. For the liver, Rosa measures ALT and AST, gamma GT, bilirubin and albumin, which show how your liver is working. They are not cancer tests.

What it tells you, and what it does not

A high AFP does not mean cancer. Hepatitis, cirrhosis, heavy drinking and blocked bile ducts can raise it. And some people simply have slightly higher levels all their lives.

A normal AFP does not rule out liver cancer: many tumours, especially small ones, do not raise it.

What matters most is how it changes over time. A value that rises from one check-up to the next weighs more than a single number.

Your doctor reads it together with other tests:

Normal alpha-fetoprotein levels

The lab decides what is normal. Many lab reports give an AFP below 10 ng/mL. Some labs report it in IU/mL, a different unit: always compare your value with the range on the same report.

In pregnancy, AFP in the mother’s blood rises because the baby makes it. That is normal, and in pregnancy the value is read with your gynaecologist.

Each lab uses its own method. To follow it over time, it is best to have your blood taken at the same lab every time.

Why alpha-fetoprotein can be high

Often the cause is a liver that is inflamed or repairing itself, not cancer.

If you have cirrhosis or chronic hepatitis

People with cirrhosis, or some kinds of chronic hepatitis, have a higher risk of liver cancer. That is why they have regular check-ups, usually with an ultrasound scan every six months.

Sometimes the hepatologist adds AFP to the scan. That is their call, and the two tests are read together.

If AFP rises from one check-up to the next, your doctor usually orders other scans to find out why.

If your alpha-fetoprotein is above the limit

Try not to worry: the cause is often the liver, not cancer. Where to start:

When to talk to a doctor

Talk to your doctor if:

Frequently asked questions

High alpha-fetoprotein in adults: what does it mean? Often that the liver is inflamed or repairing itself, for example with hepatitis or cirrhosis. Sometimes it comes from certain cancers. Only your doctor, with other tests, can tell why.

What are normal alpha-fetoprotein levels? Many lab reports give a value below 10 ng/mL. Some labs use a different unit, so the range on your own report is what counts.

Alpha-fetoprotein in pregnancy: why does it rise? Because the baby makes it, and some passes into the mother’s blood. That is normal. In pregnancy the value is read with your gynaecologist.

Is alpha-fetoprotein a good liver check? Not for people who feel well. Other tests, such as ALT and AST, show how your liver is working. People with cirrhosis have check-ups with ultrasound, sometimes with AFP, as their hepatologist decides.

Does Rosa test alpha-fetoprotein? No. Rosa is a general prevention check-up and does not include tumour markers. It measures ALT and AST, gamma GT, bilirubin and albumin, which show how your liver is working. If your doctor thinks AFP is useful, they order it separately.

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