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Having radiotherapy to the chest can cause shortness of breath during and after radiotherapy. Shortness of breath will usually improve a few weeks after treatment but for some people it can continue long term. 

Short term effects on the lungs

Radiotherapy to the chest area can cause:

  • dry cough
  • shortness of breath

This is because radiotherapy causes inflammation of the lungs, which is called acute radiation pneumonitis (pronounced new-mon-eye-tiss). This condition should improve a few weeks after treatment. 

Always let your doctor, radiographer or nurse know if you are short of breath. 

Rarely shortness of breath might be because of a more serious condition, such as a chest infection or a blood clot in the lung. 

Longer term effects

After radical radiotherapy to the chest, there is a risk of long term breathing problems. Radical radiotherapy means a long, intensive course of treatment that aims to try to cure your cancer.

Long term breathing problems are called chronic radiation pneumonitis. They cause a long term cough and sometimes breathlessness.

Let your doctor or nurse know if you notice changes in your breathing any time after your radiotherapy. You might need some treatment if the breathing changes are caused by radiation pneumonitis.

You need to tell your radiotherapy doctors if you have a heart condition that makes you breathless or if you have a heart pacemaker. Radiotherapy can make heart conditions worse over many years for some people.

Last reviewed: 
11 Feb 2019
  • Devita, Hellman and Rosenberg's Cancer Principles and Practice of Oncology (10th edition)
    VT Devita, TS Lawrence and SA Rosenberg
    Wolters Kluwer Health, 2015

  • Cancer and its Management (7th edition)
    J Tobias and D Hochhauser
    Wiley Blackwell, 2015

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