Lung cancer is caused by lung cells growing out of control. As the number of cells grow, they form into a tumour.4 The lungs are a pair of organs in the chest that supplies the body with oxygen, and removes carbon dioxide from the body. They have two parts, the right and the left. The right lung has three lobes, while the left lung has two lobes. Lung’s major passages and structures include the windpipe (trachea), bronchi, bronchioles, and alveoli.5
Many lung cancers start in the cells lining the bronchi. These cells increase to form a tumour which may cause a blockage in the lung and give rise to breathing problems. When lung cancer progresses, it can grow into surrounding structures, spread into lymph nodes that surround the bronchi and to other parts of the body as well.5 See Types and Staging of Lung Cancer section for more information.
4. ACS. Non-Small Cell Lung Cancer. Available at: https://www.cancer.org/content/dam/CRC/PDF/Public/8703.00.pdf. https://www.cancer.org/content/dam/CRC/PDF/Public/8705.00.pdf. https://www.cancer.org/content/dam/CRC/PDF/Public/8706.00.pdf. Accessed: 2 May 2019.
5. ICS. Understanding Cancer of the Lung. 2014 Edition. Available at: https://www.cancer.ie/sites/default/files/content-attachments/cancer_of_the_lung_2016_web.pdf. Accessed: 2 May 2019.