Lung Cancer
Cancer is a disease in which abnormal cells in the body grow out of control. Cancers are named after the part of the body where the abnormal cell growth begins.
Lung cancers are cancers that begin in the lungs. Other types of cancers may spread to the lungs from other organs. However, these are not lung cancers because they did not start in the lungs. When cancer cells spread from one organ to another, they are called metastases.
Research has found several risk factors for lung cancer. A 'risk factor' is anything that changes risk of getting a disease. Different risk factors change risk by different amounts.
The risk factors for lung cancer include smoking and being around others' smoke, things around us at home or work (such as radon gas), and personal traits (such as having a family history of lung cancer).