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What are the side-effects of radiotherapy?

If you have been diagnosed with a brain tumour, there are a variety of possible treatment options. One of these is radiotherapy, which may be used on its own or in conjunction with other treatment options.

What is radiotherapy?

Radiotherapy uses controlled doses of invisible, high energy beams of charged particles to destroy tumour cells whilst causing as little damage as possible to surrounding cells.

It may be used:

  • where surgery isn't possible
  • after surgery to kill any remaining tumour cells
  • to prevent a tumour from returning
  • to slow down the growth of the tumour.

Side effects of radiotherapy

It is likely that you will experience some side-effects after having radiotherapy as a brain tumour treatment. Most will be temporary and gradually fade, usually within 6 - 12 weeks after treatment has finished.

Radiotherapy works because it does the greatest damage to rapidly dividing cells, such as tumour cells. However, it can also affect any normal cells within the treatment area, particularly those which also divide rapidly such as skin cells, cells lining the mouth and digestive tract, plus blood cells in the bone marrow.

Side-effects will depend on the dose and length of treatment you have, and will differ according to the area of the brain that has received radiotherapy.

You are not radioactive after treatment and are safe to be around people, including children.

Common short-term side effects of radiotherapy

  • tiredness
  • hair loss
  • skin sensitivity
  • feeling nauseous or having a reduced appetite
  • a potential worsening of the symptoms caused by your tumour due to temporary swelling in the treatment area
  • increased risk of infection, bruising and nosebleeds caused by a slowing of blood cell production.

Potential long-term side effects of radiotherapy

Radiotherapy is designed to limit the chance of permanent side-effects as much as possible and very few people develop long-term difficulties. 

However, the benefits of having radiotherapy far outweigh the risks.

In these rare cases, long-term side-effects of radiotherapy can affect your:

  • cognitive skills
  • vision
  • hormone levels (particularly if the treatment area is close to the pituitary gland at the base of the brain)

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