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Radiotherapy to relieve pressure or a blockage

Radiotherapy can be the quickest way of shrinking a cancer and relieving symptoms when tumours block passages in the body.

Symptoms caused by a blockage or pressure

Tumours can block passages in the body such as the wind pipe or food pipe.  For example, a growth in your digestive system can stop food passing through and cause pain, bloating and sickness. 

You might have difficulty swallowing if you have an advanced stage head and neck cancer, such as cancer of the larynx or cancer of the mouth. 

Or your cancer might press on your windpipe and make it difficult for you to breathe. 

Pressure from a tumour in the body can also cause a range of symptoms including pain. 

Nerve pain

Nerve pain is caused by your tumour pressing on nerves, or by damage to nerves. It is also called neuropathic pain. It is usually more difficult to treat than other types of pain. 

People often describe nerve pain as a burning feeling or as if something is crawling under their skin. Nerve pain is usually in one area of the body. 

A course of radiotherapy can shrink your tumour so that there is less pressure on the nerve and you have less pain.

Pain from pressure on a body organ

Your tumour may press on a body organ. For example, a tumour in the bowel may press on your stomach or liver. A course of radiotherapy might shrink the tumour to relieve the pressure. 

Cancer that has spread to the liver can cause pressure on the fibrous covering of the liver itself. There are nerves in this membrane and it can be quite painful. Radiotherapy may help to shrink the tumour and relieve the pressure.

The aim of radiotherapy treatment

Radiotherapy can sometimes be the quickest way of shrinking a cancer and relieving symptoms. It can be especially good if a growing cancer is causing pressure on nearby parts of the body or blocking a tube, such as the bowel. 

The treatment won't cure your cancer. But it will help you feel better and can slow the cancer down. This can give you a better quality of life for a longer time.

Radiotherapy treatment aims to shrink your tumour and relieve your symptoms as quickly as possible. The cancer may grow back again but could take a while to do so. The radiotherapy may relieve your symptoms for some time but no one will be able to say exactly how long.

Having radiotherapy to relieve a blockage

How you have the treatment depends on whether you have external beam radiotherapy or internal radiotherapy.

External beam radiotherapy

To have the treatment you lie on a radiotherapy couch. The radiographers will help you to get into the right position and put on any moulds that you may need.

External radiotherapy machine

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 very still during the treatment. The radiotherapy couch can be quite hard. You can ask your doctor or specialist nurse if you can take a painkiller half an hour beforehand if you think it might help.

You may have just 1 treatment or a series of treatments given daily for a few days.

Internal radiotherapy (brachytherapy)

Internal radiotherapy is also called brachytherapy and doctors use this for tumours in some parts of the body. For example, if you have a tumour in your food pipe (oesophagus), your doctor might decide that the best way to shrink it is with brachytherapy. You have a tube put down your nose and into your food pipe. This is known as an NG tube or nasogastric tube. 

Using a scan, the doctor positions the NG tube next to the tumour. They then connect the tube to the brachytherapy machine and leave the room. The radiographers watch you from a closed circuit television screen. 

The machine contains a small radioactive metal ball which travels into the tube. This treatment gives a high dose of radiotherapy directly to the cancer. Very little radiation reaches the surrounding healthy tissues. The treatment lasts a few minutes. 


Once the treatment is finished, the radioactive metal goes back into the machine. The radiographers come in and remove the tube from your food pipe. 

Treatment results

Radiotherapy takes a little while to begin to work. We can’t say how long your particular treatment will take to work because this general information page covers a lot of different situations. But your specialist would usually expect to see some improvements in your symptoms within a few days.

Possible side effects

This type of radiotherapy doesn't usually cause many side effects and they tend to be mild. The side effects tend to come on as you go through your treatment course and may last for a week or two after the treatment has ended.

You might feel more tired than before the treatment started. 

If you have external radiotherapy your skin may go red in the treatment area. 

You may feel sick if your stomach is in the treatment area. To help control this, your doctor or nurse can give you anti sickness medicines (anti emetics). You might find that it helps to take an anti sickness tablet 20 minutes before your treatment.

If your bowel is in the treatment area, you might have some diarrhoea. Your doctor or nurse can give you some medicines to help control diarrhoea.

Last reviewed: 
14 Mar 2016
  • External Beam Therapy
    Peter Hoskin
    OUP Oxford, 30 Aug 2012

  • Radiotherapy in practice - Brachytherapy (2nd edition)
    P Hoskin, C Coyle
    Oxford University Press, 2011

  • De Vita, Hellman, and Rosenberg's Cancer: Principles and Practice of Oncology (9th edition)
    De Vita, V.T., Lawrence, T.S. and Rosenberg S.A.
    Lippincott, Williams and Wilkins, 2011

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