Lung Cancer

The lungs are a pair of cone-shaped breathing organs inside the chest. The lungs bring oxygen into the body when breathing in and send carbon dioxide out of the body when breathing out.

The two main types of lung cancer are non-small cell lung cancer and small cell lung cancer. The types are based on the way the cells look under a microscope. Non-small cell lung cancer is much more common than small cell lung cancer.

Most cases of lung cancer are caused by smoking. Lung cancer is the leading cause of death from cancer in the U.S. For most patients with lung cancer, current treatments do not cure the cancer.