The lungs are a pair of cone-shaped breathing organs in the chest. The lungs bring oxygen into the body as you breathe in. They release carbon dioxide, a waste product of the body's cells, as you breathe out. Each lung has sections called lobes. The left lung has two lobes. The right lung is slightly larger, and has three lobes. A thin membrane called the pleura surrounds the lungs. Two tubes called bronchi lead from the trachea (windpipe) to the right and left lungs. The bronchi are sometimes also involved in lung cancer. Tiny air sacs called alveoli and small tubes called bronchioles make up the inside of the lungs.
Anatomy of the respiratory system, showing the trachea and both lungs and their lobes and airways. Lymph nodes and the diaphragm are also shown. Oxygen is inhaled into the lungs and passes through the thin membranes of the alveoli and into the bloodstream (see inset).
There are two types of lung cancer: small cell lung cancer and non-small cell lung cancer.
See the following PDQ summaries for more information about lung cancer:
- Lung Cancer Screening
- Non-Small Cell Lung Cancer Treatment
- Small Cell Lung Cancer Treatment
Lung cancer is the leading cause of cancer death in both men and women.
More people die from lung cancer than from any other type of cancer. Lung cancer is the second most common cancer in the United States, after skin cancer.
The number of new cases and deaths from lung cancer is highest in black men.