Radiotherapy

Key Points

• Radiotherapy is the use of high-energy rays to cure or control cancer.
• Radiotherapy can be given on its own or with surgery, chemotherapy or hormone therapy. It can be given before or after surgery.
• Radiotherapy is usually given in special cancer treatment centres.
• Radiotherapy can be given from outside the body (externally) or from inside (internally).
• Your treatment will be carefully planned on your first visit to the radiotherapy unit.
• With external beam radiotherapy the radiation comes from a machine called a linear accelerator.
• Internal radiotherapy is called brachytherapy. It involves putting radioactive seeds or rods directly into the tumour or beside it.
• A course of external radiotherapy can last 4–8 weeks. Brachytherapy may involve just one treatment.
• Radiotherapy in general is safe. Depending on the type of radiotherapy, you may need to take special precautions after treatment.
• Radiotherapy may cause side-effects that can last for a short or a long while.
The side-effects depend on the part of the body being treated. Some side-effects of external radiotherapy are fatigue, skin soreness and hair loss in the treated area.
• The side-effects of brachytherapy may include soreness or bruising where the tubes applicators were placed. If the prostate gland is treated, there may be some blood in your urine.

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What is radiotherapy?

Radiotherapy is the use of high-energy rays to cure or control cancer. These beams of radiation are more powerful than ordinary X-rays. They aim to destroy the cancer cells with as little damage as possible to normal cells.

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Why is radiotherapy used?

Radiotherapy can be given on its own or with other treatments, such as surgery, chemotherapy or hormone therapy. It can kill cancer cells directly or shrink a tumour to make it easier for the surgeon to remove. Radiotherapy after surgery can prevent any cancer cells left in your body from growing.

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When is radiotherapy given?

Radiotherapy can be given before or after surgery. When it is given before surgery, it is called neo-adjuvant therapy. When given after surgery, it is called adjuvant therapy.

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Where is radiotherapy given?

Radiotherapy is usually given in special cancer treatment centres. The radiotherapy unit may not be located in the hospital where you receive your cancer diagnosis. As a result, you may have to travel to a special radiotherapy centre for treatment.

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What are the different types of radiotherapy ?

There are different ways to give radiotherapy. It can be given from outside the body (externally) or from inside (internally). Sometimes both are used to treat cancer, for example, in the breast or prostate gland. Giving radiotherapy externally is called external beam radiotherapy. Giving radiotherapy internally is called brachytherapy .

External beam radiotherapy

With external beam radiotherapy the rays come from a machine called a linear accelerator. There are also different types of external beam radiotherapy. Some of these include:

• Conformal radiotherapy (3D)
• Intensity-modulated radiotherapy (IMRT)
• Stereotactic radiotherapy

Conformal radiotherapy

This is also called 3D conformal radiotherapy. Here CT or MRI scans are used to make a three-dimensional (3-D) computer image of your tumour and nearby tissues. This allows a higher dose of radiation to be given to the cancer and a much smaller dose to normal tissue. This helps to reduce the risk of long-term side-effects.

Intensity-modulated radiotherapy (IMRT)

With IMRT, your specialist can change the dose and match the shape of the rays to the shape of your tumour. All of the tumour gets the same dose of radiation, while healthy tissues close to the tumour can get a low dose. This helps to prevent long-term side-effects.

Internal radiotherapy (brachytherapy)

Internal radiotherapy involves putting radioactive seeds or rods inside your tumour. This is used in the treatment of prostate, cervical and endometrial cancer. Internal radiotherapy can also be given as radioisotopes to treat thyroid cancer. It can be taken as a drink or capsule or as an injection into a vein.

• Low dose rate (LDR) brachytherapy
• High dose rate (HDR) brachytherapy

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How is external beam radiotherapy given ?

Planning visit:

Planning your treatment is an important step. Your first visit to the radiotherapy unit will be for planning your treatment only. You will be asked to lie on a hard table and stay still for a few minutes while a machine called a simulator takes X-rays and scans of the area to be treated. This will help to plan the correct position for your radiotherapy.

Before treatment can begin, your skin will be marked to show where the treatment is to be aimed. This is done with ink or a permanent tattoo. The rays are then aimed at the same area each day. Do not rub off any marks made with ink until your treatments are over. This planning visit can take up to 45 minutes.

Treatment visits:

You will visit the radiotherapy unit each weekday from Monday to Friday with a rest at weekends. This could last for up to 8 weeks. The radiotherapy machine moves around your body but does not touch you and makes very little noise. It is like having an X-ray and you will not feel anything during the treatment. You will be on your own in the treatment room but the radiation therapists will be able to see and hear you.

The treatment visits are much shorter than the planning visit. The treatment only lasts for about 5 minutes but your appointment will take about 15–20 minutes. This is because the radiation therapists will need time to put you in the right place on the treatment table.

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How is internal radiotherapy (brachytherapy) given ?

The way internal radiotherapy is given depends on the dosage: for example, low dose rate or high dose rate. If radioisotopes are used, for example with thyroid cancer, it can be given as a drink or capsule or as an injection into a vein.

Low dose rate (LDR) brachytherapy

Low dose rate brachytherapy involves putting radioactive seeds directly into your tumour and leaving them there permanently. In Ireland, LDR brachytherapy tends to be used for treating men with prostate cancer. You will need to go to the operating theatre to have the seeds put in.

Before the operation:

During the operation:

After the operation:

High dose rate (HDR) brachytherapy

High dose rate brachytherapy is used mainly to treat cancers in the head and neck area, the cervix, womb, prostate or the skin. High dose rate (HDR) brachytherapy involves a temporary implant of radioactive material (the source). Tubes called applicators are put into your tumour under general anaesthetic so that the radioactive source can reach the tumour. The radioactive source stays close to or inside the tumour for a few minutes. After the treatment the radioactive source and the tubes are removed.

Radioisotopes for thyroid cancer

For cancer of the thyroid the radiation source may be unsealed open . It involves using a liquid source of radiation called a radionuclide radioisotope . It can be given as an injection into a vein but is more usually taken by mouth as a capsule. Unsealed sources are radioactive until your body gets rid of them.

Before treatment you will be brought to a special room with an ensuite. Here you will be asked to take a capsule of radioactive iodine. You will have to stay in this room for a number of days as your urine and stools will be radioactive. Usually after 3 days you will be allowed home. Your doctor, nurse or physicist will advise you on any precautions that need to be taken about this type of treatment.

A booklet called Understanding Radiotherapy is available from the Irish Cancer Society. It gives more details about radiotherapy in general. A DVD on radiotherapy is also available.

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How long will my course of radiotherapy last?

How much treatment you receive will depend on the size, location and type of cancer. Your treatment will be planned to suit your situation. Even patients with the same type of cancer may have different radiotherapy treatments. Your doctor will discuss this with you.

With external radiotherapy, treatment can last from 4 to 8 weeks. With low dose rate brachytherapy, you will have one visit to put the seeds in and they stay in permanently. With high dose rate brachytherapy you may need only one treatment.

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Is radiotherapy safe?

In general radiotherapy is safe. Depending on the type of radiotherapy you receive, you may have to take some special precautions.

External radiotherapy:

It is safe to be with other people, including children, throughout your treatment.

Low dose rate brachytherapy:

Although the seeds are radioactive, you are not. It is fine for you to be among people. But you do need to be careful around women who are pregnant and young children. It is fine for you to give them a quick hug or to be in the same room as them. But it is best not to allow children to sit on your lap or sit next to a pregnant woman for long periods of time for 2 months after treatment.

High dose rate brachytherapy:

You may have to stay in hospital for a few days. Certain safety measures will be taken to prevent exposing hospital staff and your friends and relatives to radiation. Once the treatment is over, there is no risk of harming your family or friends with radiation.

Radioisotopes:

Special care will be taken after treatment with a liquid radioisotope.

• You will most likely be in a side room, away from the main ward.
• The doctors and staff on the ward will only stay in your room for short periods at a time.
• Children and pregnant women will not be allowed to visit.
• The level of radiation in your room will be monitored. The nurses may wear a small radiation counter.
• Visitors may only be allowed to stay in the room or sit at the end of the bed for a very short time, if at all.
• You will only be in the single room for a short time. Do bring books and magazines to read. You will also be able to watch TV or listen to the radio.

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What are the side-effects of radiotherapy?

Radiotherapy may cause side-effects that last for a short or long time. Remember not everyone experiences side-effects in the same way. The side-effects depend on the part of your body being treated.
Common side-effects of external radiotherapy are:

• Tiredness and fatigue
• Skin changes/soreness
• Hair loss

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Tiredness and fatigue

You might start to feel tired 3–4 weeks into treatment. Travelling to and from the radiotherapy centre may make you feel even more tired. A free booklet called Coping with Fatigue gives helpful advice and is available from the Irish Cancer Society at the following number.

Skin changes/soreness

You may notice that your skin on the treated area becomes red and sore and looks a little like sunburn. Talk to the radiation therapists or nurses at the hospital about skin care and what creams to use. Avoid perfumed soaps or powders on the area being treated. When drying your skin, pat it gently with a soft cotton towel. Because the treated area is sensitive after radiotherapy, do not expose it to the sun. Wear a sunscreen (factor 15) and protective clothing, such as a hat or long sleeved shirts. Avoid direct sunlight, especially during the hours of 11am and 3pm.

Hair loss

Radiotherapy can cause hair loss. This hair loss occurs only in the area of the body that is being treated. This loss is usually temporary and your hair will grow back a few months after treatment is over.

What are the side-effects of brachytherapy?

You might feel sore where the tubes applicators were placed or notice some bruising. If you have brachytherapy to your prostate, there may be some blood in your urine. If you are unable to pass urine even though your bladder is full, contact the hospital or your GP. This happens in about 1 in 10 men and a tube catheter   may need to be put in again to let things settle down.

All of these effects are normal so try not to worry. The side-effects might last for about 4–6 weeks after treatment but should improve over time. For more information on side-effects of external and internal radiotherapy, please contact the Irish Cancer Society.

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Where can I get more information?

The following booklets are free of charge from the Irish Cancer Society:

• Understanding Radiotherapy
• Understanding Radiation Therapy: A Patient Pathway (DVD)
• Coping with Fatigue

• Walk-in service: Visit us in person at the Irish Cancer Society offices at 43/45 Northumberland Road, Dublin 4 (Monday–Friday 9am–5pm)
• Email service
• Message Board: Visit our online bulletin board
• CancerChat Chat live with a specialist cancer nurse.

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Useful websites:

• Cancerbackup (UK) :
• Cancer Research (UK) :
• National Cancer Institute (US) :

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