Getting diagnosed
Hairy cell leukaemia is a rare type of chronic leukaemia. It develops slowly from white blood cells called .
The 2 most common types of chronic leukaemia are:
chronic myeloid leukaemia (CML)
chronic lymphocytic leukaemia (CLL)
We have separate information about the tests you might have for CML and CLL.
Find out about the tests for other types of leukaemia
Hairy cell leukaemia tends to develop slowly, so symptoms can be mild at first. Some people don’t have any symptoms and are diagnosed after having a routine blood test for something else.
Find out more about the symptoms of hairy cell leukaemia
People with symptoms that could be due to cancer, usually start by contacting their GP surgery. Your first appointment may be a telephone appointment. Your GP surgery then might arrange for you to go in and see a doctor or other healthcare professional.
Your GP can do some tests to help them decide whether you need to see a specialist. This usually includes:
physical examination
blood tests
Depending on the results of your examination and blood tests, your GP may arrange for you to have other tests such as an x-ray or ultrasound scan. You usually have these tests at your local hospital.
Read about what to expect when you see your GP
Your doctor usually asks you to lie or sit down. They look at and feel your skin all over your body to check for any abnormalities or areas that are swollen. Things they look for include signs of bleeding, bruising and infection.
They may also listen to your chest and tummy (abdomen) to find out if they sound normal.
You can ask for someone else to be in the room with you if you want, to act as a chaperone. A chaperone is a trained healthcare professional such as a nurse. A friend or relative can also stay with you for support. They can be with you during the examination.
Blood tests can check your general health including:
how well your liver and kidneys are working
the number of blood cells in your blood such as , and You may hear this being called a full blood count
if you have any signs of infection
Find out more about having a blood test
Depending on your symptoms and the results of your blood tests, your GP might arrange for you to go to the hospital. Sometimes this is quite quick, and you might have to go there straight away. This can happen if your GP suspects that you have leukaemia.
The specialist you see at the hospital is called a haematologist. This is a doctor who specialises in diseases of the blood such as leukaemia.
Your specialist usually repeats the blood tests done by your GP. You also have more tests such as:
tests on blood sample cells. This is also called immunophenotyping
a bone marrow test
tests to look for changes in the of your leukaemia cells
scans such as an ultrasound scan and a CT scan
Immunophenotyping are tests to look for certain proteins on the surface of the leukaemia cells. This is one of the most important tests you have. The results are usually all your doctor needs to confirm a diagnosis of hairy cell leukaemia.
A specialist laboratory does these tests. Sometimes doctors use a technique called flow cytometry to do immunophenotyping.
Immunophenotyping is usually done using blood samples. But your doctors may also use bone marrow samples.
These tests can also help to find out how well treatment is working and if your leukaemia has gone away after treatment.
You have this test to check whether there are cancer cells in your bone marrow. The bone marrow is the soft inner part of the bones where new blood cells are made. This can help to find out more about the type of hairy cell leukaemia you have.
You usually have this test under local anaesthetic. This means that you are awake but the area is numb.
During a bone marrow biopsy, your doctor or specialist nurse removes a sample of bone marrow cells, or an area of bone marrow in one piece. They usually take these samples from the back of your hip bone.
A specialist doctor called a pathologist looks at the tissue under a microscope.
Read more about having a bone marrow test
There are different tests that look for changes in the genes of your leukaemia cells. These are also called genetic tests.
Doctors look for changes in specific genes. For example, the BRAF V600E gene. People with typical or classical hairy cell leukaemia usually have a change (mutation) in this gene. This is different for people with hairy cell leukaemia variant (HCL-V).
These genetic tests help your doctor find out more about the type of leukaemia you have and your outlook.
Find out more about hairy cell leukaemia variant
You may have some scans to check for hairy cell leukaemia.
Ultrasound scans use sound waves to create a picture of a part of the body. You might have an ultrasound scan to see if your or liver is bigger than normal.
Read more about having an ultrasound scan
CT (or CAT) stands for computer (axial) tomography. It is a test that uses x rays and a computer to create detailed pictures of the inside of your body. The computer puts them together to make a 3 dimensional image.
You may have a CT scan of your abdomen to look for changes in your liver and spleen. It can also check if any of your are swollen (enlarged).
Find out more about having a CT scan
The tests you have help your doctor find out if you have leukaemia and the type of leukaemia you have.
Find out more about hairy cell leukaemia
This is important because doctors use this information to recommend the best treatment for you.
Read about the treatment options for hairy cell leukaemia
Coping with a diagnosis of hairy cell leukaemia can be difficult. There is help and support available for you and your family.
Read about what you can do to cope with a diagnosis of hairy cell leukaemia
Last reviewed: 25 Sept 2024
Next review due: 25 Sept 2027
Hairy cell leukaemia (HCL) is a rare type of chronic leukaemia. It develops slowly from white cells called B lymphocytes.
Hairy cell leukaemia variant (HCL-V) is a separate type of leukaemia from the typical or classic hairy cell leukaemia.
Symptoms of hairy cell leukaemia can include frequent infections and swelling of the tummy. Some people don't have symptoms.
There are many different types of leukaemia and the treatment varies for each of them. Get information about the main types.
Find out about tests to diagnose cancer and monitor it during and after treatment, including what each test can show, how you have it and how to prepare.
Hairy cell leukaemia (HCL) is a rare type of chronic leukaemia. It develops slowly from white blood cells called B lymphocytes. Find out about this type of leukaemia.

About Cancer generously supported by Dangoor Education since 2010. Learn more about Dangoor Education
Search our clinical trials database for all cancer trials and studies recruiting in the UK.
Meet and chat to other cancer people affected by cancer.
Questions about cancer? Call freephone 0808 800 40 40 from 9 to 5 - Monday to Friday. Alternatively, you can email us.