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Radiotherapy to relieve pressure or a blockage

Cancer can block passages in the body, such as the windpipe (trachea) or put pressure on organs or nerves. This can be painful and can cause other symptoms. Radiotherapy can help to shrink the cancer and relieve symptoms when this happens. 

It won't cure your cancer but can make you feel better and give you a better quality of life for a longer time.


Cancer growing into passages can cause some problems. This includes cancer in the:

  • food pipe - which can cause difficulty swallowing
  • bowel - this can stop waste from passing out of your body and make you constipated
  • wind pipe - which can make it difficult to breathe

Nerve pain (neuropathic pain)

Cancer pressing on your nerves can cause 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. 

Pain from pressure on a body organ

Your cancer may press on a organ. For example, a cancer in the bowel may press on your stomach or liver.

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.


External beam radiotherapy

You have your treatment in the hospital radiotherapy department. You might have 1 treatment or up to 10 treatments given over 2 weeks. This depends on the type of cancer.  You are most likely to have a short course of a few treatments over a few days.

To have treatment you lie on a radiotherapy couch. The radiographers (sometimes called radiotherapists) help you to get into the right position and put on any moulds that you might need.

External radiotherapy machine

Once you are in the right position your radiographers leave you alone in the room while you have the treatment. This is so they are not exposed to radiation. They can see and hear you the whole time.

It can be uncomfortable to lie very still during the treatment. This is because the radiotherapy couch can be quite hard. 

Internal radiotherapy

You might have brachytherapy with radioactive metal for cancers in some parts of the body. For example, if you have a tumour in your food pipe (oesophagus). 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 cancer. They then connect the tube to the brachytherapy machine and leave the room. They can see and hear you the whole time. 

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. 

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: 
22 Jan 2019
  • External Beam Therapy (2nd edition) 
    Peter Hoskin
    Oxford University Press, 2012

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

  • Devita, Hellman and Rosenberg's Cancer Principles and Practice of Oncology (10th edition)
    VT Devita, TS Lawrence and SA Rosenberg
    Wolters Kluwer Health, 2015

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