How is lung cancer diagnosed?

In this section, we explain how lung cancer is diagnosed and the tests you can expect. We also cover the stages of lung cancer that can be diagnosed.

Stages of lung cancer

There are four stages of lung cancer. Each stage tells you the size of the tumour and if it has spread to another part of the body.  

Stage 1    

The cancer is inside the lung and has not spread. It is usually less than 4cm. This is sometimes called early-stage lung cancer.

Stage 2

The cancer inside the lung has grown, but it has not yet spread. It is usually less than 7cm.

Stage 3

The cancer may have grown. It may have also spread to the lymph nodes or other parts of the lung. Lymph nodes help the body fight infection and disease.

Stage 4

The cancer has spread to another part of the body. This is also known as secondary or advanced cancer.   

Tests for diagnosing lung cancer

If your doctor thinks you might have lung cancer, you’ll be referred to a fast-track lung cancer clinic. If you live in England, you should be seen by a cancer specialist within two weeks of your GP referral. There are similar waiting times for the rest of the UK.

Tests for lung cancer are used to find out if you have cancer, and what stage the cancer is. Tests can include:  

  • CT scan - this uses an X-ray machine to make a detailed image of the inside of your body. 
  • Biopsy - this is when a sample of tissue is taken from the tumour. 
  • Bronchoscopy - this is when your doctor uses a thin, flexible telescope, called a bronchoscope, to look inside your lungs.
  • Endobronchial ultrasound (EBUS) - this is like a bronchoscopy but can give clearer results. It allows the doctor to scan and take samples of lymph nodes.
  • PET-CT scan - this is to show if the cancer has spread to other areas of your body. 
  • MRI scan - this is also used to find out if the cancer has spread to another part of the body. 
  • Blood tests - to check for changes in your genes that are known to cause lung cancer. This can help to give you more targeted treatment.

Get support

Call or WhatsApp our Helpline for support with your condition. Get advice on your medicines, symptoms or travelling with a lung condition, or just call us to say hello.

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