About lung cancer

The lungs

Your lungs surround your heart in your chest cavity (the thorax) and consist of spongy tissue with a rich blood supply. Air passes from your nose and mouth into the trachea (windpipe) and into each lung, through two airways called the bronchi. These divide into smaller airways, called bronchioles, which divide again and end in alveoli. These are air sacs with walls just one cell thick. It's here that oxygen filters into and carbon dioxide filters out of the blood.