Lung cancer is an abnormal growth in the tissues of the lung. When you breathe in, air goes down your trachea (windpipe), and into the lungs, where it spreads through tubes called bronchi (air passages). Most lung cancer begins in the cells that line these tubes.
There are 2 main types of lung cancer:
- Non-small cell lung cancer is the most common type of lung cancer.
- Small cell lung cancer is less common, but spreads quickly to other parts of the body through the blood.