February 25, 2014
Lung cancer is a cancer (malignancy) that originates in the tissues of the lungs or the cells lining the airways. Lung cancer originates when normal lung cells become cancer cells, usually after a series of mutations, and begin to divide out of control. A malignant (cancerous) lung tumor is distinguished from a benign (non-cancerous) lung tumor in that it can spread (metastasize) to areas of the body distant from the original tumor.
One of the big risk factors is cigarette smoking it has 7,000 different chemicals and many are poisonous. 70 of those chemicals are known to cause cancer. Second hand smoke affects about 3,000 people who never smoke, die from lung cancer due to second hand smoke every year. Radon is a naturally occurring gas that comes from rocks and dirt and can get trapped in houses and buildings. It cannot be seen, tasted, or smelled. According to the U.S. Environmental Protection Agency (EPA), radon causes about 20,000 cases of lung cancer each year, making it the second leading cause of lung cancer. Nearly one out of every 15 homes in the U.S. is thought to have high radon levels. The EPA recommends testing homes for radon and using proven ways to lower high radon levels. Family history is also another risk factor that can cause lung cancer. Your risk of lung cancer may be higher if your parents, brothers or sisters, or children have had lung cancer. This could be true because they also smoke, or they live or work in the same place where they are exposed to radon and other substances that can cause lung cancer. Radiation therapy to the chest can also cause you to get lung cancer. Cancer survivors who had radiation therapy to the chest are at higher risk of lung cancer. Patients at highest risk include those treated for Hodgkin disease and women with breast cancer treated with radiation after a mastectomy (but not a lumpectomy).