How is myeloma treated?
The treatment chosen for you depends on several factors including the stage of your myeloma, your general health, your age, the treatment you have had in the past, the response you have had to previous treatment and any complications or side effects you have experienced with previous treatments.
If you have symptoms and require treatment, it will be aimed at reducing the amount of myeloma to achieve as long a remission as possible, or at a minimum to stabilise the disease to stop its progression. Over time you may be treated with several different types of therapy depending on the effectiveness and side effects experienced. Additionally, treatments may be needed to control symptoms (such as pain or nausea) and to prevent or treat complications of the disease (such as hypercalcaemia, bone fractures and kidney failure).
Treatment for myeloma may involve the use of:
- blood stem cell transplantation
- experimental treatments with drugs not yet available for general use e.g. through clinical trials.
As myeloma is usually present throughout the bone marrow, chemotherapy is one of the main forms of treatment used to control it. Chemotherapy drugs (also called cytotoxics) damage and kill cells. Most cancer cells are more vulnerable to the effects of chemotherapy than normal cells, but some normal cells are also damaged. This is why most patients experience some side effects while they are having chemotherapy. Myeloma treatment often combines chemotherapy drugs with corticosteroids (most commonly dexamethasone or prednisolone) and an immunomodulatory drug or a proteasome inhibitor. The chemotherapy drug or drug combination that you initially receive will depend on what the ultimate treatment plan for you is. This will be discussed with you before you start treatment. These drugs are usually given in several cycles (or courses) with a rest period of a few weeks in between each cycle. This is to allow the body to recover from the side effects of the drugs.
This treatment has been shown to keep the myeloma under control effectively in many people for a period of time. It achieves this better than standard chemotherapy alone.
Radiotherapy is a type of treatment that uses high energy x-rays to kill cancer cells and shrink tumours. Radiotherapy is generally regarded as local therapy because it only destroys cancer cells in the treated area. Radiotherapy can be used in a number of different ways to treat myeloma. In some cases isolated masses of myeloma cells, like plasmacytomas, may be successfully treated using radiotherapy alone.
Radiotherapy is also used to treat areas of bone that have become weakened as a result of myeloma. This helps to reduce bone pain, and the risk of bone fractures. Occasionally radiotherapy to the whole body (total body radiotherapy) is used in preparation for an allogeneic stem cell transplant.
Other types of therapy
There has been a great deal of research in myeloma over the last 10 years and several new forms of treatments have become available. These therapies work very differently to standard chemotherapy. The addition of these therapies has improved the outcomes for people being treated with myeloma.
- Immunomodulatory drugs (IMiDs) are drugs derived from thalidomide. They act by impacting on the immune system, have anti-inflammatory properties, reduce the body’s ability to produce new blood vessels, and reduce the ability for the myeloma cells to multiply. These drugs include thalidomide and lenalidomide.
- Proteasome inhibitors are targeted therapies that work by blocking the action of proteasomes, which are found in all cells throughout the body. Proteasomes act as the “waste disposal unit” for cells, breaking down and recycling proteins from old cells. Proteasome inhibitors block the waste disposal unit in myeloma cells, affecting their growth and survival. An example of a proteasome is bortezomib.
An autologous bone marrow transplant or peripheral blood stem cell transplant is used to treat some people with myeloma who have no other serious illnesses. In a small number of cases an allogeneic bone marrow or peripheral blood stem cell transplant using a suitably matched donor may be considered. This is generally reserved for younger patients (those under the age of 60) because of the risks associated with this treatment.
Treating relapsed myeloma
Finding out that your myeloma has come back (relapsed) or is resistant to standard treatment can be devastating. It is important to remember, however, that there are usually several options for treating the disease and getting it back under control. The main options for treatment of relapsed or refractory myeloma are thalidomide, bortezomib or lenalidomide, used alone or in combination with corticosteroids and chemotherapy. Selected patients may also undergo a second autologous stem cell transplant or, less often, proceed to an allogeneic transplant.
The choice of treatment will depend upon your previous treatment and your response to that treatment, the side effects you have experienced with treatment, your general health and your personal preferences. Promising new and experimental treatments are being developed for myeloma all the time. Your doctor will be able to discuss with you all of the treatment options available including suitable clinical trials.