Radiotherapy

Produced by Stephanie Hughes, Bupa Health Information Team, February 2012.

This factsheet is for people who are having radiotherapy, or who would like information about it.

Radiotherapy uses radiation, usually X-rays, to treat cancer. A beam of radiation is targeted at part of the body where the cancer is. The aim of the treatment is to destroy cancer cells with minimal damage to the surrounding healthy tissue.

Your care may differ from what is described here as it will be designed to meet your individual needs. It’s important that you discuss your radiotherapy with your doctor.

About radiotherapy

Radiotherapy can be used to treat many different types of cancer. About four out of 10 people who have cancer will have radiotherapy as part of their treatment.

Radiotherapy works by destroying the DNA inside cancer cells, preventing them from reproducing and so shrinking cancerous tumours. Healthy cells will also be affected but they are better able to repair themselves.

Radiotherapy can be used for the following reasons.

• To destroy the tumour – this may include radiotherapy on its own or combined with other treatments such as surgery or chemotherapy. If the aim is to cure your cancer with radiotherapy, this is known as primary therapy or radical radiotherapy.
• To reduce the size of a tumour before surgery. This is called neo-adjuvant treatment.
• To make sure all the cancer cells are destroyed after surgery. This is called adjuvant treatment.
• In the emergency treatment of a cancer pressing on your spinal cord to reduce the size of the cancer and prevent damage to your nerves.
• In advanced cancer to slow down the progress of the disease, relieve pain and other symptoms. This is called palliative treatment.

Radiotherapy may be given as one or two treatments, or more often, as a course of treatment usually requiring daily visits on weekdays for between one and six weeks.

Preparing for radiotherapy

Planning a course of radiotherapy can take some time. To find the exact position of the cancer, your doctor will use X-ray pictures and CT scans, to make a three-dimensional image of your body. You may also have MRI scans, which uses magnets and radiowaves to produce images of the inside of your body. Before your treatment starts you will need to come to the radiotherapy department where a special machine called a simulator is used to help plan the exact location and dose of radiation.

The area to be treated has to be positioned accurately each time. To help this, you may have a few tiny dots tattooed on your skin. Occasionally, if the area has to be kept very still, you may need to have a mould made. For example, if your head and neck area is to be treated, you may need to wear a see-through plastic mask or brace to make sure your head remains in exactly the same position for each treatment.

You may have a blood test to see if you have anaemia (low amounts of red blood cells in your blood). If so, you may need to have a blood transfusion to increase the amount of oxygen your blood can carry around your body.

If you smoke, stop – research has shown that giving up smoking may make radiotherapy more effective and reduce possible side-effects of the treatment.

If you have had radiotherapy before to treat a previous cancer, it may be possible to have radiotherapy again to a different area of the body. However, this may differ from person to person so it’s important to discuss your treatment options with your doctor.

What happens during radiotherapy

In most hospitals, a number of different health professionals are involved in providing treatment. This is known as a multidisciplinary team. A clinical oncologist (a doctor who specialises in cancer care using radiotherapy and chemotherapy) will oversee your treatment. The radiotherapy equipment is operated by a therapy radiographer, a healthcare professional trained in using X-rays for treatment. A nurse specialist is often your key contact during treatment and will be available to offer you help and support. You may see other health professionals including a physiotherapist, dietitian and pharmacist. Behind the scenes, medical physicists are responsible for calculating safe and effective doses of radiation.

There are two main types of radiotherapy treatment – external radiotherapy and internal radiotherapy.

External radiotherapy

External radiotherapy is delivered by a machine known as a linear accelerator. It produces high-energy beams of radiation, either as X-rays or gamma rays.

The course of treatment will be planned by a clinical oncologist. He or she will plan your treatment by taking into account the size of your cancer, its likely sensitivity to radiation and the sensitivity of your surrounding tissues. He or she will also take into account your general health and fitness, and will discuss any possible side-effects that you may need to prepare for.

The number and duration of your radiotherapy sessions depends on the type of cancer and where it's located in your body. A superficial skin cancer may need only a few treatments, whereas a cancer deeper in your body may need longer treatment. It may also depend on whether you’re having treatment to cure the cancer or treatment to reduce your symptoms.

External radiotherapy is given in daily doses called 'fractions'. For each fraction of radiotherapy you will be asked to sit or lie down in a fixed position. The radiotherapy equipment can be positioned with great accuracy to target the beam of radiation exactly on the right spot. This may involve lying down while the machine rotates around you, or you may be asked to sit in a chair while the beam is directed at a tumour that is near the surface of your skin. The machine won't actually touch you at any point, but it can be quite noisy, with whirring and buzzing sounds. There is an intercom so you can communicate with the radiographer at all times.

Radiotherapy won't make you become radioactive during or after the treatment because no radiation-producing material gets inside your body. You will be able to carry on with many of your normal daily activities. However, you may feel tired during and after your treatment so it's a good idea to ask friends and family for help and support if you need it.

                                                           External radiotherapy

Internal radiotherapy

Internal radiotherapy is where the source of radioactivity is put inside your body so it can get closer to the cancer. This can be done in two ways:

Brachytherapy

This is when a solid source of radiation is put next to a tumour to give a high dose of radiotherapy. This means the effect on healthy tissue around the cancer is as little as possible. Brachytherapy can be used to treat cancers of the cervix, womb (uterus), prostate and skin.

For women who have gynaecological cancers, such as cervical cancer, the radiation source is placed inside the vagina during the treatment. This means you may need to stay in hospital for a day or two during treatment.

For other cancers, you may need to have a minor operation under general anaesthesia to put the radioactive source into your body. This may be removed after several hours or even days. Hospital visiting may be restricted at this time because you will be radioactive while the source is in place.

For prostate cancer, small radioactive pellets, known as seeds, are placed into the prostate gland. These deliver a steady dose of radiation to the prostate. This type of source gradually loses its radioactivity and stays in your body permanently. This won’t cause you any harm.

Radioisotope therapy

This is when a radioactive substance, a radioisotope, is used to treat your cancer. It may be given either as an injection into a vein, capsules that you can swallow or as a liquid you can drink. Radioisotope treatment is often used for cancers of the thyroid gland.

After radioisotope therapy, your body will give off small amounts of radiation so you may need to stay in isolation for some time after treatment and then take precautions, such as not getting close to pregnant women or children, for several days afterwards. The radioactive material leaves your body in your sweat and urine. You may be given advice on safety precautions, such as flushing the toilet twice after urinating, to minimise any risk to other people.

Recovering from radiotherapy

After the treatment, your clinical oncologist will arrange a follow-up appointment to check how you're recovering from any side-effects and what your response has been to the radiotherapy. This is a good opportunity to discuss any concerns or to ask about any long-term side-effects that you might expect to have after your treatment.

Patient support groups can give you support and advice on recovering after radiotherapy.

What are the risks?

Side-effects

These are the unwanted, but mostly temporary, effects of a successful treatment. The side-effects may vary depending on what part of your body is treated and the type and dose of your radiotherapy. You will be given information about the side-effects specific to you before you start treatment.

Depending on which part of your body is treated, possible side-effects immediately after radiotherapy may include:

• tiredness
• loss of appetite
• feeling sick and vomiting
• diarrhoea
• red, sore or itchy skin
• coughing and shortness of breath
• a dry mouth or sore throat, causing difficulty swallowing
• weight loss
• hair loss – usually temporary but it can be permanent (this only happens in the area of the body being treated)
• emotional symptoms – feeling low, depressed or anxious after treatment
• stiffness of joints and muscles

Radiotherapy can also cause some long-term side-effects such as:

• darkening of your skin
• your hair may grow back a different texture and colour
• hair loss that is sometimes permanent
• tiny red marks on your skin from broken blood vessels
• swelling of your arms and legs, due to the blockage of lymph vessels (this is called lymphoedema)
• shortness of breath – if you have had radiotherapy to your chest
• difficulty swallowing due to narrowing of your gullet (oesophagus)
• infertility – if your ovaries or testicles are within the treatment area

Some, but not all people who have radiotherapy to the pelvic region may have side-effects related to their bowel, bladder or sexual function. Your doctor and specialist nurse will be able to offer you advice and support.

Very rarely, radiotherapy can cause a second cancer that may develop several years after treatment. The benefits of the radiotherapy outweigh this risk but it may be something that your doctor will mention to you and is also one of the reasons patients are followed up after treatment.
 

For answers to frequently asked questions on this topic, see FAQs.

For sources and links to further information, see Resources.