The myelodysplastic syndromes (MDS)
MDS is more common in people over 60, but it can happen at any age. It is also sometimes called myelodysplasia.
People with MDS have an abnormality of their bone marrow. This means they don't make enough healthy blood cells. Sometimes in MDS, the bone marrow makes blasts that don't develop (mature) or work properly.
How MDS affects you will depend on the type you have. In some people it may develop slowly, while in others it may be more aggressive. Some types of MDS are at greater risk of developing into acute leukaemia. Your specialist can explain more about the type of MDS you have.
MDS is a group of conditions that affect the bone marrow. Bone marrow is a spongy material found inside the bones. It produces cells known as stem cells. All the blood cells in the body develop from stem cells.
Stem cells make blood cells that aren't fully developed (immature) called blasts. As the blasts develop (mature) they become one of the three main types of blood cells:
red blood cells, which carry oxygen to all cells in the body
white blood cells, which are essential for fighting infections
platelets, which help the blood to clot and prevent bleeding.
The bone marrow makes millions of blood cells every day. While blood cells are developing they stay inside the bone marrow. When they are mature they leave the bone marrow and enter the blood stream.
In most cases the cause of MDS is unknown. This is called primary MDS. In a small number of people, MDS develops as a result of previous treatment with chemotherapy or radiotherapy. This is known as secondary or treatment-related MDS.
Signs and symptoms of MDS
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The main symptoms of MDS are caused by low levels of healthy blood cells. These symptoms include:
feeling weak, tired (fatigued) and breathless due to a lack of red blood cells (anaemia)
repeated infections because the number of white blood cells (which help fight infection) in the blood are low
bruising or bleeding more easily because of a low number of platelets (cells which help the blood to clot) in the blood.
Some people are diagnosed with MDS when they have a routine blood test, before any symptoms have developed.
You will usually be seen by a doctor specialising in blood disorders (a haematologist). MDS is diagnosed with blood tests and a bone marrow sample.
Full blood count (FBC)
This is a blood test that counts the numbers of red blood cells, white blood cells and platelets in your blood.
Bone marrow sample
Your bone marrow sample will be tested to find out more about the type of MDS you have. Tests such as cytogenetic tests are done.
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 first.
The doctor will then pass a needle through the skin into the bone and draw a small sample of liquid marrow into a syringe (bone marrow aspirate). After this, the doctor will take a small core of marrow from the bone (a trephine biopsy). Both samples will then be looked at under a microscope.
The sample can be taken on the ward or in the outpatients department. The whole procedure takes about 15–20 minutes. It may be uncomfortable as the marrow is drawn into the syringe, but this only lasts for a few seconds.
You may feel bruised and have an ache for a few days after the test. You can take some mild painkillers to ease this.
The cells in our body contain chromosomes, which control the activities of the cell. There may be changes in the structure of chromosomes in MDS. Tests look for particular chromosomal changes (cytogenetics). These tell the doctor the subtype of MDS you have (see classification of MDS below) and the risk group you are in.
MDS can be divided up (or classified) into different subtypes. Different systems are used to do this. In the UK, doctors usually classify MDS according to the World Health Organisation (WHO) system.
The WHO system looks at how many abnormal, immature cells (blasts) there are, and the characteristics (cytogenetics) of the abnormality. The major subtypes are:
refractory anaemia, with or without ring sideroblasts (RA or RARS)
refractory cytopenia with multilineage dysplasia (RCMD)
refractory anaemia with excess blasts (RAEB)
unclassified (does not fit into the above groups).
MDS is also divided into risk groups. This depends on a person's full blood count, the number of blasts in their bone marrow, the results of cytogenetic tests and whether they need blood transfusions. The risk group helps your doctors decide on the best treatment for you.
The bone marrow is only slightly affected and the disease develops slowly.
The disease is slightly more advanced. This risk group is often split into two sub-groups: low-intermediate and high-intermediate risk.
The bone marrow is more widely affected and the disease can progress more quickly.
Knowing the subtype of MDS that you have and the risk group you are in helps your doctors plan the most appropriate treatment for you, and predict how well the MDS may respond to it.
The treatment that's most appropriate for you will depend on the type of MDS you have, the risk group you’re in, your personal preferences and your general health.
Some people with low- or intermediate-risk MDS and no symptoms may not need treatment to begin with. If you don't have treatment you will have regular check-ups and your blood count will be monitored. This is sometimes called watch and wait.
Most people with MDS have treatment at some point to control and improve the symptoms caused by low blood counts. This is usually called supportive treatment. Sometimes this may be the only treatment that's needed.
Chemotherapy may be helpful for some people depending on the type of MDS they have.
A small number of people who are fit enough to cope with very intensive treatment may be able to have a stem cell transplant from a donor. The aim of this is to cure the disease.
There are also some newer treatments available which may be used to help to control MDS.
You may be invited to join a clinical trial looking at new ways of treating MDS. Your haematologist can tell you about any trials that would be suitable for you.
Supportive treatment aims to reduce symptoms caused by MDS and to improve your quality of life.
Symptoms such as anaemia, or bruising and bleeding, are caused by low levels of healthy red blood cells or platelets in the blood. You can have blood or platelet transfusions to help improve your symptoms.
If you have a lot of blood transfusions, there is a risk of too much iron building up in your body. This is because red blood cells contain iron. High levels of iron can be harmful, and you may need treatment to reduce the amount in your body. Your doctor or nurse will explain more about this treatment if you need it.
Blood cell growth factors
It may be possible to boost the number of healthy red and white blood cells in your blood with blood cell growth factors.
A drug called erythropoietin may be used to increase the amount of red blood cells in your blood and reduce the number of blood transfusions you need. It may also help to control the disease.
G-CSF is a drug that may be given to boost the number of white blood cells.
Both of these drugs are usually given as injections under the skin (subcutaneously). Some people may benefit from having a combination of these drugs.
Reducing your risk of infection If your white blood cells are low, you’re at increased risk from infections. Your specialist nurse or doctor will give you advice about reducing this risk.
You may be prescribed antibiotics and anti-fungal treatments to treat or prevent infection.
Chemotherapy is the use of anti-cancer (cytotoxic) drugs to destroy cancer cells. It may be given to help control the disease and any symptoms.
Chemotherapy can be given as tablets or as an injection into a vein (intravenously). Your treatment may involve just one type of chemotherapy, or a combination of drugs.
The type of chemotherapy you’re given will often depend on your age and how the disease is affecting you (the risk group).
Combinations of different chemotherapy drugs, similar to those used to treat acute leukaemia, may be used for people with high-risk MDS. The aim of this treatment is to remove all traces of MDS and get the bone marrow working normally (remission). This is intensive treatment that is usually only suitable for younger people because of its side effects.
Donor (allogeneic) stem cell transplants
A small number of people with MDS may be able to have a stem cell transplant from a donor. Usually the donor is a brother or sister but may occasionally be an unrelated donor.
This is a very intensive treatment and is not without risks so it is only suitable for some people. The risks involved with a transplant increase as you get older. Your specialist will discuss the possible benefits and risks of this treatment with you.
Before a donor stem cell transplant, you will be given treatment to destroy the unhealthy bone marrow and 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. Some people may have less intense doses of chemotherapy before being given donor stem cells. This called reduced intensity conditioning or a ‘mini transplant’.
The donor's healthy stem cells are then put into your blood through a drip. The stem cells make their way to the bone marrow and start to make red and white blood cells and platelets.
This chemotherapy drug may be used for people with higher risk MDS who are unable to have a stem cell transplant. It may help the bone marrow to work more normally.
Azacitidine is given as an injection under the skin (subcutaneously). Side effects include discomfort at the injection site, feeling sick (nausea) and tiredness (fatigue). It also temporarily reduces the blood count.
Lenalidomide (Revlimid©) is a type of biological therapy that affects the way the immune system works. It can be used to treat people with low-risk MDS. It is currently being tested on its own and with chemotherapy in people with high-risk MDS. Lenalidomide is taken as a capsule by mouth.
These drugs may help to control MDS and improve symptoms. Your haematologist can give you more information about them.
Everyone has their own way of dealing with their illness and the different emotions they experience. You may find it helpful to talk things over with family and friends or your doctor or nurse. You can also contact our cancer support specialists or the organisations listed below for more information and support.
Leukaemia & Lymphoma Research
Leukaemia & Lymphoma Research provides information on the myelodysplastic syndromes and other blood disorders.
Leukaemia CARE is a national group promoting the welfare of people with leukaemia and related blood disorders, including the myelodysplastic syndromes.
MDS UK Patient Support Group
MDS UK Patient Support Group is the only MDS dedicated patient support group in the UK. It offers networking opportunities, organises patient meetings, shares information and raises awareness across the UK.
This section has been compiled using information from a number of reliable sources including:
Lee, et al. Wintrobe’s Clinical Hematology. 12th edition. 2009. Lippincott Williams and Wilkins.
Guidelines for the Diagnosis and Therapy of Adult Myelodysplastic Syndromes. British Journal of Haematology. 2003. 120:187–200.
Thanks to Dr Jyoti Evans, Haematologist, and all 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.