Lung cancer is one of the most common cancers in the world and is a leading cause of cancer-related death in men and women in the United States according to the American Cancer Society. Although cigarette smoking is the main cause of lung cancer and quitting would prevent a large number of lung cancer cases, it wouldn't prevent all of them. A recent study led by researchers at the National Cancer Institute suggests that about 10 percent of men and 20 percent of women who develop lung cancer have never smoked and that there are three molecular subtypes of lung cancer in people who have never smoked. Read More