Tests for acute myeloid leukaemia (AML)

• A full blood count (FBC) counts the different types of cells in the blood.
• A blood film or smear lets doctors assess leukaemia cells in your blood.
• A bone marrow biopsy tests soft spongy tissue from your hip bone.
• Genetic tests look for changes in chromosomes or DNA in cells.
• You’ll have a general health test and be screened for infections.

Some people are told they might have AML after going to their GP with symptoms and having a blood test called a “full blood count”. If your blood results suggest that AML is a possibility, you might be phoned and told to come to hospital urgently. Most people need to start treatment quickly, sometimes even within a few hours or days. In other cases, it might be safe to wait longer before starting treatment. Your doctors will discuss this with you.

Other people visit A&E as an emergency because they suddenly get very unwell and do not know why. They’ll be checked in A&E and have tests, and they might be told in hospital or soon afterwards about the possibility of AML.

A full blood count measures the number of each type of cell in the blood – red blood cells, white blood cells and platelets. In AML, you can have too many of some blood cells, and not enough of others.

A sample of blood will be taken from a vein in your arm and sent to the lab for testing.

If you’re diagnosed with AML, you’ll have regular FBCs to monitor your condition. Find out more about blood counts in AML and what the results mean.

A blood film means taking a sample of your blood to look at under a microscope. This allows the doctors to see if you have any leukaemia cells in your blood, and what they look like.

If doctors suspect AML, one of the first things they’ll want to check is whether you have a subtype of AML called acute promyelocytic leukaemia (APL), which has different treatments. APL cells look different to AML cells under the microscope. If you have APL, read our information about acute promyelocytic leukaemia (APL).

AML begins in the bone marrow, so checking the bone marrow for leukaemia cells is an important test. This is one of the main tests used to confirm a diagnosis of AML.

Bone marrow is a soft, spongy tissue found in the centre of large bones. It is where the body makes its blood cells.

A bone marrow biopsy involves removing a sample of bone marrow from your hip bone. This can be looked at under a microscope.

AML is usually diagnosed if the number of myeloid blasts (immature blood cells) in your bone marrow is between 1 in 10 (10%) and 2 in 10 (20%) or more.

Find out more about bone marrow biopsies.

Tests can be done on a sample of your blood or bone marrow.

Some of these tests look for any changes (mutations) in the chromosome structure of the abnormal cells. These include

• cytogenetic testing
• karyotyping
• FISH testing.

Other tests look for changes in the DNA structure of the abnormal cells. These include:

• polymerase chain reaction (PCR) tests
• DNA sequencing tests.

Sometimes these results can confirm a diagnosis of AML. They can also help your doctor plan the most effective treatment, as some mutations can be targeted by specific drugs.

Find out more about genetic mutations and AML.

Immunophenotyping is a test that looks at which proteins (markers) are on the surface of the abnormal cells or inside them. This can help to tell doctors whether you have AML.

If you are diagnosed with AML, you’ll have a general health check. This will help work out your risk of side effects from treatment, and whether high-intensity or lower intensity treatment might be best.

You’ll have a range of tests to check your general health. These might include:

• tests of your heart, liver and kidney function
• tests for viruses like HIV and hepatitis B and hepatitis C
• a combination of blood tests
• a chest X-ray
• heart checks like ECG (electrical tracing of the heart) and echocardiogram (heart ultrasound).

Your hospital team will talk to you about what the results of these tests mean for your treatment.

Not everyone needs a stem cell transplant. But if your doctor thinks you might in the future, they will talk to you about tissue typing. There is lots to consider but if you decide to go ahead, tests are needed to confirm your tissue type. Then the aim is to find a bone marrow donor with a tissue type that matches yours closely. This could involve testing your sisters or brothers (siblings) if you have any. There are also registries of people who have volunteered to donate bone marrow, which your team can use to search for an unrelated donor.

Even if you might not need a stem cell transplant now, your doctor might talk to you about tissue typing, in case you need a transplant later.

We explain more about stem cell transplants in the high-intensity treatment information.

We have more general information about other tests that are often used in blood cancer.