Tests for myelofibrosis (MF)

If doctors suspect you have myelofibrosis (MF), you will have tests to confirm that is the right diagnosis. They will be checking that it is MF and not another type of blood cancer such as essential thrombocythaemia (ET), polycythaemia vera (PV), or another health condition.

A full blood count or FBC is a simple blood test which measures how many of each type of cell there is in your blood. A sample of your blood is analysed by an automated counter.

This test will show whether your red blood cells, white blood cells and platelets are within the normal range.

We have general information about blood counts. What’s normal varies depending on things like your sex and ethnic background, so check with your hospital team what’s the normal range for you.

Doctors will look at a small sample of your blood under a microscope to check for cells which are not developing normally.

They will look in particular for red blood cells shaped like teardrops, instead of their usual rounded shape. Teardrop-shaped red blood cells are a sign of myelofibrosis.

You may have blood tests to check how well your kidneys and liver are working, and to look for signs of other diseases.

These tests are done using a sample of your blood, which is analysed in a laboratory. Doctors will look for changes to genes called JAK2, CALR or MPL. Abnormalities in these genes mean you may have myelofibrosis (MF), or another blood condition. See What is myelofibrosis (MF)? for more information.

You may be sent for a chest X-ray to check whether your symptoms could be caused by another condition such as tuberculosis (TB) or lymphoma.

You may have an ultrasound scan of your stomach area (abdomen). This is to examine your spleen and your liver, which can be swollen if you have myelofibrosis.

The person who does the ultrasound scan is called a sonographer. They will apply gel to the surface of your abdomen and run a probe over the area they need to scan. The probe records images which can be seen on a computer screen.

To get a good image, the sonographer may need to press the probe firmly on to your abdomen. This will feel cold and may feel uncomfortable, especially if your spleen is swollen.

Sometimes people with symptoms of myelofibrosis (MF) may be referred for a CT scan rather than an ultrasound. This will focus on your liver and spleen and helps doctors decide if the diagnosis is MF or another condition with similar signs and symptoms.

CT scans are painless. You will be asked to lie still on a flat bed which moves through the scanner. The scanner is doughnut-shaped and doesn’t enclose your whole body. The scan can take between 10 and 30 minutes.

You will probably need a bone marrow biopsy. This is a minor surgical procedure used to collect samples of bone marrow to test in the laboratory. You will have a local anaesthetic and you won’t have to stay in hospital overnight.

Samples are taken from the back of your pelvis (the ring of bones at the base of your spine). One sample is taken using a thin needle (an aspirate) and another using a thicker one (a trephine) to get a larger “core” of bone marrow.

Doctors will examine your samples under the microscope. They will be looking for bone marrow scarring, which is typical of myelofibrosis (MF), and other visible changes in your cells.

A sample of your bone marrow will also be analysed for genetic changes.

You may find it helpful to read our information about bone marrow biopsies and talk things through with your hospital team or our Support Service.

Most people will have a bone marrow biopsy to confirm that MF is the correct diagnosis. You may also need one to check on your progress from time to time if you have treatment for MF.

If you get a diagnosis of myelofibrosis (MF), you will normally have some tests repeated when you have a check-up. You will have regular check-ups whether or not you need treatment. Some people don’t need treatment when they are diagnosed.

You will have a full blood count (FBC) before each appointment, and your specialist doctor (consultant) will discuss the results with you. They may also feel (palpate) your spleen to see if it is swollen or order an ultrasound scan to check your spleen if you need one.

You will be asked if you have noticed any change in your symptoms, or any new symptoms. Some people keep a symptoms diary to help with this. Your hospital team may use a system called the MPN Total Symptom Score to rate your symptoms on a scale of one to ten.

If there are any signs that the MF is progressing, you may have other tests, including a blood film and bone marrow biopsy, but these are not routine.

If you are at risk of blood clotting (thrombosis) or bleeding (haemorrhage) because of the myelofibrosis, or because of another condition like heart disease or diabetes, your specialist doctor will speak to your GP.

Your GP will be responsible for monitoring your heart and blood vessels (your cardiovascular system) and treating any conditions that might affect them. This will include checking:

• how well your heart is working
• your blood pressure
• your cholesterol levels
• your blood sugar levels.

Take any medicine your GP prescribes and take their advice about lowering your risk of blood clots and bleeding. This might include thinking more carefully about what you eat and how you exercise.