Radiotherapy for secondary bone cancer
Radiotherapy treats cancer by using high energy x-rays to destroy cancer cells, while doing as little harm as possible to normal cells.
The treatment is given in the hospital radiotherapy department. It’s the most common type of treatment for secondary bone cancer because it’s very effective at relieving symptoms such as pain and swelling.
Radiotherapy is usually given by aiming high-energy x-rays at the affected bone from a radiotherapy machine. This is known as external radiotherapy. Sometimes a type of internal radiotherapy called a radioisotope is used.
Radiotherapy for secondary bone cancer can be given in different ways. Sometimes a single dose is given. Sometimes treatment may be Pided into a number of sessions, which are given as daily treatments.
The way your treatment is given depends on the type of primary cancer you have and where the secondaries are in the body.
Your doctor will discuss your treatment with you beforehand and answer any questions you have.
Radiotherapy is normally given just to the area of the bone affected by the cancer. It usually takes 7-10 days for radiotherapy to start reducing bone pain, and it may take up to six weeks before you feel the full effect. You may notice that the pain becomes slightly worse before getting better. During this time, it’s important to continue taking the painkillers prescribed by your doctor.
As the pain improves, it may be possible to reduce the amount of painkillers. However, it’s important to discuss this with your doctor or nurse before adjusting the dose.
External radiotherapy does not make you radioactive and it’s perfectly safe for you to be with other people after treatment, including children.
Side effects of external radiotherapy
Usually, this type of radiotherapy causes very few side effects. However, treating bones in certain areas of the body, such as the ribs or the spine, may cause some sickness for a couple of days after the treatment. If you have radiotherapy treatment to your pelvis, this may cause diarrhoea. These side effects can usually be prevented by taking anti-sickness (anti-emetic) or anti-diarrhoea medicines.
Before the treatment starts, your doctor, nurse or radiographer (who gives the radiotherapy) will discuss with you any likely side effects. They’ll also arrange for you to have any drugs you may need to manage these side effects.
Internal radiotherapy using radioisotopes
Back to top
Radioisotopes are radioactive substances. Some radioisotopes are taken up (absorbed) by bone. These are sometimes used to treat secondary bone cancers.
The radioisotope is usually given as a liquid, which is injected into a vein, usually in the arm. The radioisotope travels through the bloodstream to the bones, where it gives a dose of radiotherapy to the areas affected by the cancer cells. This can help to reduce pain, often within a few days, but sometimes it will take a few weeks to start working.
The advantage of radioisotope treatment is that all the bones affected by cancer will be treated. So it can be a helpful treatment if several of your bones are affected. However, it’s only suitable for treating bone secondaries that come from certain types of primary cancer.
strontium-89 or samarium-153 may be used to treat secondaries from cancer of the prostate or breast
iodine-131 may be used to treat secondaries from cancer of the thyroid.
Strontium-89 is given as a single injection through a small tube (cannula) inserted into a vein. People are normally given the injection as an outpatient. Pain caused by the cancer normally reduces several weeks after the injection. In most people, the pain relief lasts for several months. The treatment is sometimes repeated if the pain comes back.
After the injection of strontium-89, it’s safe to be with other people, including children. However, your urine and blood will be very slightly radioactive for about seven days afterwards. You’ll be given advice to follow to reduce any risk to others.
Samarium-153 can usually be given as an outpatient. It’s given as an injection through a small tube inserted into a vein.
A drip (intravenous infusion) may be given before and after the injection. For some people, pain may start to get better about one week after treatment. It continues to lessen over 3-4 weeks and, for most people, pain relief lasts about four months.
After treatment, your urine will be slightly radioactive for 12 hours.
The hospital staff will give you advice on precautions you need to take to reduce any risk to others before you go home.
Iodine-131 for bone secondaries from thyroid cancer is given as a capsule that is swallowed, or as an odourless, colourless drink.
If it’s used for other types of cancer, or if it’s attached to another chemical, it’s likely to be given as a drip (intravenously) over a period of up to one hour.
The radioactivity in iodine-131 breaks down slowly so you’ll need to stay in hospital in a single room for a few days. You can go home once the radioactivity reduces to a level that’s safe for other people around you.
After treatment with iodine-131, your urine will be radioactive for a short time. This means you may need to take some precautions after going home. The hospital staff will explain these to you. There may also be a few restrictions about contact with people - especially children and pregnant women. The hospital staff will explain these to you.
Side effects of radioisotope treatment
Back to top
Radioisotopes such as strontium-89 or samarium-153 can temporarily reduce the number of normal red and white blood cells produced by the bone marrow. If the number of your red blood cells is low (anaemia), you may get tired easily. You may be given a blood transfusion if the number is very low. When your number of white blood cells is low, you’re more prone to infection. If necessary, you’ll be given antibiotics to treat any infection.
Another side effect can be tumour flare, which is a swelling around the tumour area in the days following treatment. It can cause a temporary increase in pain and tenderness, and you may need to take painkillers for a few days.