What is lung cancer?

Lung cancer is a disease where cancer cells form in the tissue of the lungs. It includes two main types which behave differently: non-small cell lung cancer and small cell lung cancer. It is the number one cause of cancer death in men and women.

What causes lung cancer?

Smoking causes most lung cancers but non-smokers may also develop lung cancer. Avoiding risk factors and increasing protective factors may help prevent lung cancer.


The following are risk factors for lung cancer:

  • Cigarette, cigar and pipe smoking
  • Second hand smoke
  • Family history
  • HIV infection
  • Environmental risk factors
    • g. asbestos exposure
    • previous radiation e.g. for breast cancer and Hodgkin’s lymphoma
  • Beta carotene supplements in heavy smokers

The following are protective factors for lung cancer:

  • Not smoking
  • Quitting smoking
  • Lower exposure to workplace risk factors

It is unclear whether diet and physical exercise decrease the risk of lung cancer

What are the symptoms of lung cancer?

You may have a cough that won’t go away or feel short of breath. You may feel pain in your chest, or cough up sputum streaked with blood. Other symptoms of lung cancer can include severe fatigue, loss of weight for no reason and swelling in the face and/or neck veins.

How is the diagnosis made?

If your doctor is worried about cancer, she will ask you some questions about your health habits (e.g. smoking) medical and family history, and send you for a series of tests.