Bone marrow is the soft material found at the centre of the bones of the body.

Myeloma doesn't usually exist as a lump or tumour. Instead, the myeloma cells divide and expand within the bone marrow.

It typically affects many places in the body where bone marrow exists, which is why it's called multiple myeloma. This includes the bones of the spine, the skull, the pelvis, the rib cage and the areas around the shoulders and hips.

Multiple myeloma may not cause any symptoms in its early stages. It may only be suspected or diagnosed after a routine blood or urine test.

However, it will eventually cause a wide range of symptoms and complications that may include bone pain and bone fractures. See Multiple myeloma - symptoms for a full list of the possible symptoms.

Who is affected

It's not known exactly what causes the plasma cells inside the bone marrow to become cancerous.

Studies have suggested that certain factors may increase your chance of developing myeloma, such as having a close relative with the condition, being obese and having a diet low in fish and green vegetables. See Multiple myeloma - causes for a full list of risk factors.

Multiple myeloma mostly affects people aged over 60. The average age of people who are diagnosed is 70.

For reasons that are unclear, rates of myeloma are twice as high in black people than in white people.

Every year in the UK, it's estimated that multiple myeloma affects 60-70 in every million people.

Outlook

Although there's no cure for myeloma, treatment can control the progression of the cancer for several years or, in some cases, many years. Treatments include chemotherapy and bone marrow transplantation.

New treatments over the last 10 years have approximately doubled survival rates and improved the quality of life for myeloma patients significantly. For more information, see Multiple myeloma - treatment.

Multiple myeloma may not cause any symptoms or complications in its early stages and may only be diagnosed after a routine blood or urine test.

However, it will eventually cause a wide range of symptoms and complications, the most common of which are described below.

Bone pain

Pain can be a symptom of the myeloma bone disease that often occurs in myeloma. The middle or lower back, the rib cage and the hips are the most frequently affected. The pain is often persistent and described as dull and aching, and usually made worse by movement.

Bone fractures

The bones that most commonly fracture due to myeloma bone disease are the spine and the ribs. Breaks can occasionally happen with only minor pressure or injury. Fractures of the bones of the spine (vertebrae) can lead to collapse of the spine, height loss and, occasionally, compression of the spinal cord (main column of nerves running down the back).

Compression of the spinal cord can cause 'pins and needles', numbness and weakness in the legs and feet, and sometimes problems passing urine and stools.

Fatigue

Patients with myeloma often have persistent fatigue (overwhelming tiredness). This may be due to the myeloma itself or to one or more of its complications, or it may be a side effect of the treatment given.

Anaemia

Anaemia is a reduction in the number of red blood cells or the oxygen-carrying haemoglobin they contain. It can occur as a result of the myeloma itself or as a side effect of treatment. It can lead to fatigue, weakness and breathlessness.

Infection

Infection is more common in myeloma patients because the myeloma interferes with the immune system, making them more susceptible to infection.

Hypercalcaemia

Hypercalcaemia means that the level of calcium in the blood is too high. It can occur in myeloma patients as bone disease causes too much calcium to be released from the affected bones.

Kidney damage

Kidney damage can occur in myeloma patients for a variety of reasons. The abnormal protein produced by myeloma cells can damage the kidneys, as can some of the other complications, such as hypercalcaemia. Also, some of the drugs used to treat myeloma can sometimes cause kidney damage.

Studies have suggested that the factors listed below may increase your chance of developing multiple myeloma:

• having a close relative with the condition
• being obese (extremely overweight)
• having a diet that's low in fish and/or green vegetables
• having HIV or AIDS
• using hair dyes, or having a job that involves exposure to hair dyes
• working as a farmer
• working with meat
• working with sheet metals
• working in the petroleum industry
• working with radiation
• having a job that exposes you to wood dust
• having a condition where the immune system attacks healthy tissue, such as rheumatoid arthritis

It's unclear exactly how these risk factors may increase the risk of developing myeloma.

A diagnosis is almost always made by a hospital specialist, although a GP may initially suspect it and refer you to hospital for a number of tests.

The GP will examine you to check for bruising, bleeding, signs of infection and any other clues that you may have myeloma.

They will also take blood and urine tests.

Blood tests are useful for three reasons:

• they can determine whether you have abnormal antibodies in your blood
• they can find out whether your calcium levels are higher than usual
• they can count how many red and white blood cells and platelets you have (this is known as a full blood count)

A urine test can determine whether there's any underlying damage to your kidneys.

If your GP suspects you may have myeloma, they will refer you to a consultant haematologist (a specialist in blood diseases) for further tests.

Further tests

The haematologist will carry out the same assessments and may order more blood or urine tests.

If blood and urine tests suggest you may have myeloma, the next step is to assess the state of your bones.

A series of X-rays are used to check for any bone damage. Bone damage caused by multiple myeloma will often show up as dark areas on the X-rays.

If the results of the X-rays are unclear, you may also be given a magnetic resonance imaging (MRI) scan or a computerised tomography (CT) scan.

A biopsy is the final stage in confirming a diagnosis of multiple myeloma. A needle is used to take a small sample of bone marrow from one of your bones, usually the hip.

The biopsy will be carried out under a local anaesthetic (the area is numbed) so it isn't painful. The sample of bone marrow will be studied in a laboratory to check whether there are any cancerous plasma cells.

If you have myeloma, you'll be cared for by a team of healthcare professionals usually led by a consultant haematologist who specialises in myeloma.

This team of health professionals will discuss your case and recommend what they think is the best treatment option for you. However, the final decision will be yours.

Before visiting the hospital to discuss your treatment options, you may find it useful to write a list of questions that you'd like to ask the specialist. For example, you may want to find out about the advantages and disadvantages of a particular treatment.

Goals of treatment

There are two main goals in the treatment of myeloma, which are outlined below.

• Bringing the myeloma under control using various combinations of anti-myeloma treatments that remove the cancerous cells from your bone marrow.
• Treating the symptoms associated with myeloma, such as anaemia and bone pain.

Bringing the myeloma under control

Not everyone diagnosed with myeloma will need immediate treatment if their myeloma is causing no problems.

Patients who don't need treatment will be actively monitored for signs that the cancer is beginning to cause problems.

For those who need treatment, the options outlined below are the most commonly used.

It's important to understand that while myeloma is highly treatable, it's not currently curable. This means that additional treatment is always required when the cancer comes back. The most commonly used treatments for when myeloma comes back are also briefly described below.

Initial treatment may either be:

• non-intensive, for older or less fit patients
• intensive, for younger or fitter patients

There is no particular age cut-off as to who gets intensive treatment and who gets less-intensive treatment. But as a general rule, patients under the age of 60 are likely to be candidates for intensive therapy. Those over 70 are more likely to be recommended non-intensive treatment. Those aged in between will be given careful consideration as to what treatment group they fit into.

Both intensities of treatment are very effective, but intensive treatment is deemed too toxic for older or less fit patients.

All patients who require treatment will almost certainly begin with a combination of three anti-myeloma drugs.

These drugs all have different ways of working and they work very effectively together at killing myeloma cells – much more effectively than if they were given on their own.

In the younger and/or fitter group of patients, this is called induction treatment as it's almost always followed by additional treatment known as high-dose therapy and stem cell transplantation (see below).

In the older and/or less fit group, this treatment is referred to as initial or frontline treatment. It's almost always identical to the induction treatment given in the younger/fitter group, but some of the drugs may be given in slightly lower or weaker doses.

Usually, these treatment combinations comprise three drugs including a chemotherapy drug (either melphalan or cyclophosphamide), a steroid drug (dexamethasone or prednisolone) and either thalidomide or velcade.

Together with your consultant haematologist, the most appropriate combination will be chosen that best suits your myeloma and personal preferences.

The drugs are described in more detail below.

Steroids

Steroid medication is similar to a type of hormone found naturally in the body. Dexamethasone and prednisolone are steroids often used in the treatment of myeloma.

Exactly how steroids work against the myeloma cells is unclear, but it seems they encourage the immune system to stop new myeloma cells from growing in bone marrow.

Steroids are taken by mouth and are best taken at breakfast with food. Possible side effects include heartburn, indigestion, mood changes and problems falling asleep.

Thalidomide

Thalidomide is a medication that was introduced in the 1950s to treat morning sickness, and it was later found to cause birth defects.

However, research has shown that thalidomide can be effective in killing myeloma cells.

Thalidomide tablets are usually taken during the evening with food. Because of the risk of causing birth defects, it's important to use reliable contraception, such as a condom, while taking thalidomide.

It's likely that you'll have to sign a confirmation form stating that you're aware of the risks of birth defects and of the precautions that you need to take.

Common possible side effects of thalidomide include:

• sleepiness
• constipation
• loss of appetite
• headaches
• skin rashes
• numbness or tingling in the hands and feet

There's also a small but potentially serious risk that you will develop a blood clot when taking thalidomide. You may therefore be given a medication called warfarin, which helps to prevent blood clots.

Chemotherapy

Chemotherapy works in a number of different ways to directly kill myeloma cells. The two most common types of chemotherapy used in myeloma are melphalan and cyclophosphamide. These two drugs are very similar and are often used interchangeably.

These treatments are mostly given by mouth. They're reasonably well tolerated, and side effects are mild. Possible common side effects include:

• nausea
• vomiting
• hair loss
• infection
• tummy upsets

Bortezomib

Bortezomib is the first in a brand new class of anti-cancer drugs called proteasome inhibitors. It's especially effective against myeloma cells.

All cells have an internal recycling protein known as the proteasome. Cells depend on this to recycle the things it needs to grow and to dispose of things that may be harmful to their survival.

Bortezomib blocks the functioning of the proteasome, causing the myeloma cell to die.

Possible side effects of bortezomib include:

• tiredness
• nausea
• diarrhoea
• numbness or tingling in your hands and feet

There are some limitations as to which newly diagnosed patients should get bortezomib, but your doctor and/or nurse will discuss this with you.

Your doctor or nurse will tell you all about your treatment and the possible side effects to look out for. With all treatments, it's very important to let your doctor or nurse know of any side effects immediately.

Intensive treatment

Intensive treatment involves giving a very high dose of chemotherapy in an attempt to destroy a greater number of myeloma cells and cause a longer, deeper remission (remission means disappearance of the symptoms).

However, as this treatment approach also destroys the healthy bone marrow, stem cells are transplanted to rescue the bone marrow. This treatment is known as high-dose therapy and stem cell transplantation.

In most cases, the stem cells are previously collected from the patient. In very rare cases, the cells are collected from a sibling or unrelated donor.

This treatment is associated with significant side effects and requires a two to three-week stay in hospital and a three to six-month recovery period. This is why it's not generally an option for older and/or less fit patients.

Maintenance treatment

Maintenance treatment is occasionally given to try and prolong the response to treatment. However, further research is underway to establish its role in the treatment of myeloma, which patients require maintenance, and who are most likely to benefit.

Both steroids and thalidomide can be used for maintenance treatment.

Treating the symptoms and complications of myeloma

Radiotherapy

Radiotherapy can be used to help relieve bone pain. Radiotherapy involves directing high-energy waves of radiation at bones that have been weakened and damaged by cancerous cells.

The radiation reduces the number of cancerous cells in the bone, giving the bone a chance to repair itself.

You should only need one or two sessions of radiotherapy to reduce the pain.

Nausea and vomiting are the most common side effects of radiotherapy given in this way. However, these should quickly pass once the course of radiotherapy has ended.

Bisphosphonates

Bisphosphonate medication can be used to prevent bone damage and reduce the levels of calcium in your blood.

Normally, bone goes through a continuous cycle of repair, where the body replaces old bone cells with new ones.

In myeloma, cancerous plasma cells disrupt this process, causing the bones to weaken. Bisphosphonates help to stop this from happening, and eventually return the bone repair process to normal.

Bisphosphonates are either given as tablets or by injection. The most common side effects include stomach pain, nausea, vomiting and diarrhoea. Speak to your cancer team if any of these side effects are bothering you.

You'll also be encouraged to drink plenty of water to flush out any excess calcium from your blood.

Treatments for anaemia

If you have anaemia as a result of having a low number of red blood cells, blood transfusions can be used to increase your red blood cell count.

You may also be given a medication called erythropoietin, which encourages the production of new red blood cells.

Surgery

In some cases, surgery may be needed to repair or strengthen damaged bones. Compression fractures of the spine may be treated using two new surgical techniques known as:

• Percutaneous vertebroplasty: a special type of quick-drying cement is injected into the affected bone to strengthen it and reduce the risk of fracture.
• Balloon kyphoplasty: a tiny balloon is inserted into the affected vertebra (bone of the spine), inflated and removed, then the space is filled with a special type of cement.

Relapse treatment

When the myeloma returns, you will be given an additional course of a combination of anti-myeloma treatments. This involves two, or occasionally three, drugs to try to control the myeloma again.

Treatment for relapsing myeloma is based on the same principles and is very similar to treatment for newly diagnosed myeloma. However, high-dose therapy and stem cell transplantation in younger and/or fitter patients is less commonly used. Therefore most patients, regardless of age and fitness, are treated similarly.

All the drugs described above are used in various combinations in treating relapsed myeloma. However, the following important points are worth noting:

• Bortezomib is only approved for your first relapse, and patients must achieve a certain response in order to continue treatment. Your doctor and/or nurse will explain this to you.
• There is an additional drug that can treat relapses but isn't currently approved for use in newly diagnosed patients. This drug, called lenalidomide, is very similar to thalidomide but, unlike bortezomib, it's not approved for use at the first relapse but only in patients who have had a second or subsequent relapse. You'll find brief details on lenalidomide below.

Lenalidomide

Lenalidomide works in a similar way to thalidomide in that it blocks the blood supply to the cancer cells.

However, lenalidomide can reduce the number of white blood cells in your blood, therefore you'll be more vulnerable to infection.

Tell your care team if you think you may have an infection – for example, if you have a high temperature or swelling of the skin or you feel unwell.

Lenalidomide also reduces the number of platelets in your blood, which means your skin can be easily bruised and you can bleed easily. Again, you should report these symptoms to a member of your care team.

If you're taking lenalidomide, there's a small but potentially serious risk of developing a blood clot. Contact a member of your cancer team immediately if you develop pain or swelling in one of your calves, or you have chest pain and/or breathlessness.

What is the outlook?

Although there's no cure for myeloma, treatment can control the progression of the cancer for several years or, in some cases, many years. New treatments over the last 10 years have approximately doubled survival rates and improved the quality of life for myeloma patients significantly.

A number of new medications are currently being investigated in clinical studies. If successful, they should further increase the outlook for patients.

Clinical trials

As myeloma is an uncommon cancer, you may be asked to take part in a clinical trial.

Most clinical trials involve comparing a new treatment with an existing treatment to see whether the new treatment is more or less effective.

It's important to remember that if you receive a new treatment there's no guarantee that it will be more effective than an existing treatment.

Cancer treatment team