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This information is about chronic idiopathic myelofibrosis. It belongs to a group of conditions known as the chronic myeloproliferative diseases (CMPDs).
The chronic myeloproliferative diseases (CMPDs) are a group of conditions that affect how your bone marrow| works. They involve the overproduction of one or more of the blood cells that are normally produced in the bone marrow. A small number of people with a CMPD will go on to develop a form of leukaemia|.
The main types of chronic myeloproliferative disease are:
Chronic myeloid leukaemia (CML)| is also a chronic myeloproliferative disease, although it is usually dealt with as a separate condition.
This is the spongy material in the centre of some of our bones. It produces cells known as stem cells. Stem cells are early blood cells that develop into three different types of blood cells:
Chronic idiopathic myelofibrosis is a condition in which scar tissue (fibrosis) develops in the bone marrow (myelo). Chronic means that the condition usually continues for many years, and the word idiopathic means the cause is unknown. Some people may have a faulty gene| called the JAK2 gene, that might have caused their condition. This gene isn't inherited (doesn't run in families) and can't be passed on.
Myelofibrosis is a rare condition, which mainly affects people over 50. Its causes are unknown.
Myelofibrosis can develop when the bone marrow has been producing too many platelets (due to essential thrombocythaemia), or too many red blood cells (due to polycythaemia vera). It can also develop without any history of these other myeloproliferative diseases.
There are other conditions that can cause the bone marrow to become scarred, and these are treated differently. Various tests and investigations will be done to determine the exact cause.
As the bone marrow becomes more scarred (fibrosed), it is less able to produce blood cells. To help compensate for this, the liver and the spleen begin to produce blood cells, and as a result these organs become enlarged. However, the liver and spleen are not as efficient at making blood cells as the bone marrow, and this can lead to low levels of blood cells in the body. When the spleen becomes enlarged it can 'hold on' to the blood cells and is involved in their destruction.
At first myelofibrosis may not cause any symptoms. Some people are diagnosed before they have any symptoms when they have a blood test taken for another reason.
As the bone marrow becomes less able to produce enough blood cells, the following symptoms may occur:
Myelofibrosis is usually diagnosed by a haematologist (specialist in blood disorders). The diagnosis may be suspected after the results of a blood test known as a full blood count. This counts the number of red blood cells, white blood cells and platelets in the blood. You may also have a blood test to check for the JAK2 gene.
Other conditions can cause the bone marrow to become fibrosed. These need to be ruled out before a diagnosis of myelofibrosis can be made.
Your specialist may want to take a sample of marrow (biopsy) to examine under a microscope. 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.
A bone marrow sample being taken
View a large copy of the bone marrow sample being taken image|
After this, the doctor will take a small core of marrow from the bone (a trephine biopsy). Both samples will be looked at later under a microscope.
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.
If the bone marrow samples look normal, but your doctor still suspects you have myelofibrosis, they may want to take more samples from your pelvis. This is because in the early stages of the disease, not all of the bone marrow may be affected. 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 myelofibrosis aims to control symptoms without causing too many side effects, and will depend on how the disease is affecting you. For example, if you have no 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.
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 myelofibrosis, especially if the symptoms are severe.
Chemotherapy can help reduce the size of the spleen and the liver, and can help control other symptoms. It may also help increase the number of blood cells.
Chemotherapy is usually given as a tablet. A drug called hydroxycarbamide (Hydrea®)| may be given, or sometimes low doses of another drug called melphalan (Alkeran®)|.
One of the side effects of chemotherapy is that it temporarily affects the way the bone marrow works. However, chemotherapy is often given in reduced doses to help lower the risk of serious side effects.
Chemotherapy isn't suitable for everyone with myelofibrosis. If you do have chemotherapy, you'll be monitored very closely. Your doctor or nurse will explain which drugs you will have and possible side effects.
Some other drugs may be used to improve symptoms of myelofibrosis, but they're not suitable for everyone. Your specialist will tell you if they are appropriate in your situation.
This drug may be given to help improve anaemia (low number of red blood cells).
Your specialist may suggest that you have an operation to remove the spleen if you have a very low number of platelets, or if your spleen is enlarged and causing pain.
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 side effects such as tiredness and skin irritation, although generally these are mild.
A small number of younger people with myelofibrosis may be able to have high-dose chemotherapy followed by a stem cell transplant from a donor (allogeneic transplant|). Usually the donor is a brother or sister, but may occasionally be an unrelated donor.
This is very intensive treatment, so it is only suitable for younger, fitter people. The risks involved with a transplant increase as you get older.
Stem cells are blood cells at their very earliest stage of development. They are collected from the donor's blood and then stored.
You will be given high doses of chemotherapy to destroy your own bone marrow. 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, where they will start to grow and develop into mature blood cells.
Your specialist will discuss the possible benefits and risks of this treatment with you.
Research into new ways of treating myelofibrosis is ongoing. Clinical trials| are looking at the use of drugs that affect the activity of the JAK2 gene (JAK2 inhibitors).
Your doctor may invite you to take part in a clinical trial to compare a new treatment against the best available standard treatment. Your doctor must discuss the treatment with you, and have your informed consent before entering you into a trial.
Before any trial is allowed to take place, it must be approved by a research ethics committee, which protects the interests of those taking part.
You may decide not to take part or to withdraw from the trial at any stage. You will then receive the best standard treatment available.
You will need to have regular check-ups and blood tests. These will probably be ongoing. If you have any problems or notice any new symptoms in between these times, let your nurse or doctor know as soon as possible.
Everyone has their own way of dealing with their illness and the different emotions| they experience. Some people find it helpful to talk things over with family and friends or their doctor or nurse. You can also contact our cancer support specialists| or the organisations listed below for more information and support.
Leukaemia CARE| is a national group promoting the welfare of people with leukaemia and other blood disorders, including non-Hodgkin lymphoma. Has regional support groups in many counties.
Leukaemia & Lymphoma Research| provides information on myeloproliferative diseases and other blood disorders.
This section has been compiled using information from a number of reliable sources, including:
For answers, support or just a chat, call the Macmillan Support Line free (Monday to Friday, 9am-8pm)
If you have any questions about cancer, need support or just want someone to talk to, ask Macmillan.