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This information is about myelofibrosis (MF), a condition where the bone marrow becomes scarred. Myelofibrosis is also called primary myelofibrosis, myeloproliferative myelofibrosis and chronic idiopathic myelofibrosis.
We hope this information answers your questions. If you have any further questions, you can ask your doctor or nurse at the hospital where you are having treatment.
The bone marrow| is a spongy material in the centre of some of our bones. It makes cells known as stem cells. Stem cells are early blood cells that develop into three different types of blood cells:
Myelofibrosis is a type of myeloproliferative disease (MPD). In MPDs the bone marrow makes too many of one or more types of blood cells.
The main types of MPD are:
Myelofibrosis is a condition which affects the bone marrow. It is a rare condition that can affect people at any age, including children, but it's most common in people over 50.
MF can occur in people who haven’t any history of problems with their bone marrow. This is called primary myelofibrosis. MF can also develop in people who have essential thrombocythaemia (ET), or polycythaemia vera (PV). Altogether, these types are all called myelofibrosis as they behave in the same way.
People with MF may have low levels of one or more types of blood cells because as the bone marrow becomes scarred (fibrosed) it is less able to make blood cells. Some people have too few of some types of blood cells and too many of another type.
To make up for this decreased production of blood cells in the bone marrow, other parts of the body, usually the spleen and liver, begin to make blood cells.
As the spleen begins to make blood cells, it grows in size. The enlarged spleen may ‘hold on’ to blood cells, removing them from the blood circulation. It may also be involved in destroying blood cells. So the spleen may reduce the numbers of blood cells in the blood.
At first, MF may not cause any symptoms. Some people are diagnosed with MF when they have a blood test taken for another reason. When symptoms do develop, they are most often due to having too few blood cells or an enlarged spleen.
Possible symptoms include
MF is usually diagnosed by a haematologist (specialist in blood disorders). The diagnosis may be suspected after the results of a blood test called a full blood count. This test counts the number of red blood cells, white blood cells and platelets in the blood.
You may have a blood test to check for a change (mutation) in a gene| called JAK2. This gene is important in regulating the production of blood cells. The fault in the gene occurs during the person’s lifetime. It isn’t something you’re born with and you can’t pass it on to your children.
Your specialist may want to take a sample of bone marrow (biopsy) to examine under a microscope (see diagram below). The sample is usually taken from the back of your hip bone (pelvis). You will be given an injection of local anaesthetic to numb the area. The doctor will then pass a needle through the skin into the bone, and draw a small sample of liquid marrow (bone marrow aspirate) into a syringe.
After this, the doctor will also take a small core (piece) of marrow from the bone (a trephine biopsy). Both samples will be looked at later under a microscope.
A bone marrow sample being taken
View a large copy of the bone marrow sample being taken image|
The test can be done on the ward or in the outpatients department. The whole procedure takes about 15-20 minutes. It may be uncomfortable when the marrow is drawn into the syringe, but this should only last for a few seconds.
You may feel bruised and have an ache for a few days after the test. This can be eased with mild painkillers.
Sometimes, in the early stages of MF, not all of the bone marrow is affected. Because of this some people need to have a second bone marrow biopsy taken if the first samples look normal but their doctor still suspects MF.
Other tests and investigations may also be done, such as scans and x-rays. Your doctor or nurse will explain these to you.
Treatment of MF aims to control any symptoms you have, so the treatment you’re given depends on how the disease is affecting you. If you don’t have symptoms you may not need any treatment for a while. In this case, your haematologist will monitor your condition regularly. If you develop any symptoms between appointments, let your specialist know.
There are various treatments that may be used to improve symptoms of myelofibrosis, but they're not all suitable for everyone. Your specialist will tell you if they are appropriate in your situation.
If you have symptoms caused by a low red blood cell count (anaemia), you can be given blood transfusions|. Usually it is possible to have a blood transfusion as a day patient, but it may involve an overnight stay in hospital. Blood transfusions can be repeated as often as necessary.
Chemotherapy| is the use of anti-cancer (cytotoxic) drugs to destroy cancer cells. It may be used to treat MF, especially if the symptoms are severe.
Chemotherapy can help reduce the size of the spleen and the liver, and can help control other symptoms. This may also help increase the number of blood cells.
The main drug used is hydroxycarbamide (Hydrea®)|, which is given as a tablet.
Chemotherapy isn't suitable for everyone with MF. It temporarily affects the way the bone marrow works and may reduce the level of blood cells, so if you have chemotherapy you'll be monitored very closely. Sometimes chemotherapy is given in reduced doses to help lower the risk of serious side effects.
Your doctor or nurse will explain the possible side effects of any chemotherapy they recommend for you.
Thalidomide| may be used to treat MF. It’s a type of biological therapy that affects the way the immune system works. It can be given on its own or in combination with steroid tablets. Thalidomide is taken as a tablet. The side effects can include feeling tired| or drowsy, constipation| and numbness or tingling of the hands and feet|. If you feel drowsy it’s important not to drive.
Thalidomide can cause birth defects, so it should not be given to pregnant women. People taking thalidomide who are sexually active should use a barrier form of contraception.
JAK inhibitiors such as ruxolitinib (Jakafi®) are a new type of treatment. They work by blocking (inhibiting) the faulty JAK2 gene. They may be suitable for some people with severe symptoms related to myelofibrosis or an enlarged spleen.
This is a drug that may be given to help improve anaemia (low number of red blood cells)
Erythropoietins| are another treatment that may help to increase the levels of red blood cells in some people.
Steroids| may sometimes be used to treat low levels of red blood cells.
This is a protein that occurs naturally in the body. It can also be made in the laboratory. Interferon| may be given to help to reduce high levels of blood cells such as platelets or white blood cells. It is given as an injection under the skin, usually three times a week. Side effects include flu-like symptoms, dizziness and tiredness (fatigue).
If your spleen is enlarged and causing troublesome symptoms, your specialist may suggest that you have an operation to remove it.
There can be advantages and disadvantages to having this operation. Your specialist will discuss these with you before you make a decision.
If it isn’t possible to remove the spleen it may be possible to shrink it using radiotherapy|. Radiotherapy is the use of high-energy rays to destroy cancer cells, while doing as little harm as possible to the healthy cells.
Radiotherapy can help improve symptoms such as pain| and a high platelet count. But this improvement in symptoms may only last for a few months.
Radiotherapy can cause temporary side effects, such as tiredness and skin irritation, although generally these are mild.
A small number of people with myelofibrosis may be able to have a stem cell transplant from a donor (allogeneic transplant|). Usually the donor is a brother or sister but they may occasionally be an unrelated donor.
This is a very intensive treatment that carries risks, so it is only suitable for fitter people. The risks involved with a transplant increase as you get older. This treatment is not suitable for everyone and is not done routinely. Doctors take into account a person's general health and fitness before recommending them. If appropriate, your specialist will discuss the possible benefits and risks of this treatment with you.
Stem cells are blood cells at their very earliest stage of development. They are collected from the donor's blood and then stored.
Before a donor stem cell transplant, you will be given treatment to weaken your immune system so that your body doesn’t reject the donor stem cells. This is called conditioning treatment and usually involves having high doses of chemotherapy. Afterwards, you'll be given the donor's stem cells as a transfusion. The stem cells will find their way through the bloodstream to the bone marrow. There they will start to grow and develop into mature blood cells, and in time they will rebuild your immune system.
Some people may have less intense doses of chemotherapy to weaken their immune system enough to allow the donor stem cells to grow in their bone marrow. This called reduced intensity conditioning.
Research into treatments for myelofibrosis is ongoing. Cancer specialists use clinical trials| to assess new treatments. Before any trial is allowed to take place, an ethics committee must have approved it and agreed that the trial is in the interest of the patients.
You may be asked to take part in a clinical trial. Your doctor will discuss the treatment with you so that you have a full understanding of the trial and what it involves. You may decide not to take part, or to withdraw from a trial at any stage. You will still receive the best standard treatment available.
You will need to have regular check-ups and blood tests. If you have any problems, or notice any new symptoms in between these times, let your nurse or doctor know as soon as possible.
You may have many different emotions| including anger, resentment, guilt, anxiety and fear. These are all normal reactions, and are part of the process many people go through in trying to come to terms with their condition.
Everyone has their own way of coping with difficult situations. Some people find it helpful to talk to family or friends|, while others prefer to seek help from people outside their situation. Some people prefer to keep their feelings to themselves. There is no right or wrong way to cope, but help is there if you need it. Our cancer support specialists| can give you information about counselling| in your area.
MPD Voice| provides information and emotional support and fund research into MPDs.
Leukaemia CARE| is a national group promoting the welfare of people with leukaemia and other blood disorders,. Has regional support groups.
This fact sheet has been compiled using information from a number of reliable sources, including:
With thanks to: Dr Jyoti Evans, Consultant Haematologist; Dr Claire Harrison, Consultant Haematologist; and the people affected by cancer who reviewed this edition. Reviewing information is just one of the ways you could help when you join our Cancer Voices network|.
Content last reviewed: 1 January 2013
Next planned review: 2015
For answers, support or just a chat, call the Macmillan Support Line free (Monday to Friday, 9am-8pm)
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© Macmillan Cancer Support 2013
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