Radiotherapy can be used as a treatment to relieve bone pain caused by cancer that has spread into the bone.
Radiotherapy to control bone pain
Your doctor may suggest radiotherapy as a treatment to relieve bone pain caused by cancer that has spread into the bone. The areas of cancer cells in the bone are called secondary bone cancer, bone metastasis, or bony secondaries.
Radiotherapy is often used to control pain due to bone secondaries from prostate cancer, breast cancer, bowel cancer and lung cancer. It may be combined with other types of treatment, depending on the type of cancer you have.
Secondary bone cancer weakens the bones by damaging healthy bone cells. Radiotherapy can help to make bones stronger and less likely to break. It can also treat bones that have fractured.
Radiotherapy for cancer that has spread to bones can also help to prevent new painful areas developing. Having this treatment may slow down the cancer and give you a better quality of life for a longer time. But it won't cure your cancer.
How you have treatment
There are two main ways of giving radiotherapy for bone pain.
External beam radiotherapy
External radiotherapy is the most common type of treatment if you have just one or two bone secondaries. The radiation beam is directed at the affected bone from outside the body. It is a bit like having an X-ray. You may have a single treatment or a series of daily treatment sessions for up to 2 weeks.
First, you have a specialised CT planning scan so the treatment team can plan exactly where to give the radiotherapy. You might also need to have a plastic mould made to keep you still during the treatment sessions.
To have the treatment you lie on a radiotherapy couch. The radiographers help you to get into the right position.
Once you are in the right position the staff leave you alone in the room. This is so they are not exposed to the radiation. You will be alone for a few minutes. The radiographers watch you carefully on a closed circuit television screen.
You can't feel the radiotherapy. It doesn’t hurt but you may find it uncomfortable to lie in position during the treatment. The radiotherapy couch can be quite hard. Ask your doctor or specialist nurse if you can take a painkiller half an hour beforehand if you think it might help.
If you have more than 1 or 2 areas of secondary bone cancer in different parts of your body, you might have external radiotherapy to the whole of your upper body. Then about 2 to 4 weeks later, you have treatment to the lower half of your body. This is called hemibody irradiation.
To have this treatment you need to be quite fit and your bone marrow also needs to be working well. It is not a common treatment these days.
Internal radiotherapy with radioisotopes
Your doctor might suggest internal radiotherapy with radioisotopes if you have more than 1 or 2 areas of secondary bone cancer in different parts of your body.
You have an injection of a very small amount of radioactive liquid. The affected areas of bone take up the liquid. So the treatment targets the radiation where you need it.
The radiation from the injection only lasts a few days in your body. It is only a small amount but can work very well for controlling bone pain.
How well the treatment works
External radiotherapy for bone pain can ease the pain to some extent or may get rid of it altogether. The radiation kills off cancer cells that are destroying and weakening the bone. It may take several weeks to work fully.
About 3 out of 10 people (30%) have no pain within a month of radiotherapy treatment. The treatment reduces the pain by half for at least another 4 out of 10 (40%) people. So at least 7 out of 10 people (70%) have somewhere between no pain and half as much pain after their radiotherapy treatment.
By about 6 to 12 weeks after treatment the bones have repaired the damage caused by the cancer cells and they get stronger.
Studies of hemibody irradiation show that it gives nearly everyone some pain relief. It can relieve pain completely in up to half of the people treated.
It can also help to stop new painful areas developing.
Strontium treatment takes between 1 and 4 weeks to start to reduce pain. The pain relief may last for up to 18 months.
A review in the Lancet found that between 40 and 95 out of every 100 people treated (40 to 95%) have pain relief from this type of treatment.
Taking pain killers
You need to carry on taking your painkillers until the radiotherapy starts reducing the pain. But within a few weeks, sometimes less, you might be able to cut down on the amount of painkillers you take.
If you are getting more side effects from your painkillers, such as feeling drowsy, it may be a sign that you don’t need to take as many.
Let your doctor or nurse know and they can advise you about how to safely reduce your painkillers.
Repeating the radiotherapy treatment
If your first course of palliative radiotherapy doesn't work well, your doctor may recommend that you have a second course. You might also have a second course if the pain gets better but then comes back again.
The SC20 trial looked at how well a second course of radiotherapy worked for cancer that had spread to the bone.
The trial team found that the bone pain responded in around half the people who were treated. They also found that a lower dose of radiotherapy in a single session was as good as a higher dose in 5 sessions.
Side effects of palliative radiotherapy
The side effects with this treatment are usually mild. Radiotherapy for bone pain aims to relieve symptoms and so doctors aim not to cause many side effects. There is information below about the side effects of different types of radiotherapy.
The side effects of external palliative radiotherapy depend on which part of the body is treated. This type of treatment usually has few side effects including:
- feeling tired
- your skin may get red in the treatment area
- treatment can cause a flare up of pain for 1 or 2 days and you may need painkillers to help
- feeling sick if you are having treatment to your ribs, your stomach area, your pelvic area or your skull – your doctor or nurse can give you anti sickness drugs (anti emetics) and taking them an hour before your treatment might help
- having diarrhoea with treatment to your hips (pelvis), or bowel area – you can have medicines to reduce diarrhoea
The side effects tend to come on gradually as you go through your treatment course. They may last for a week or two after the treatment has finished.
With hemibody irradiation, you are likely to feel sick. So to prevent this, your doctor or nurse can give you anti sickness medicines and steroids before your treatment.
The treatment may also slow the production of blood cells by your bone marrow. So you may get anaemic and have an increased risk of infection. This is temporary.
Your doctors will keep an eye on your blood cell levels when you have your check ups.
There are very few side effects with strontium 89 treatment or radium 223 therapy.
You have some radioactivity in your body for a while after the treatment. The amount is extremely small and gets lower each day.
Your doctor or nurse will let you know if there are any safety guidelines you need to follow after your treatment. How long you have to follow these depends on the dose of treatment that you had.