According to the American Cancer Society (ACS), it is estimated that 224,210 new cases of lung cancer occurred in 2014. Lung cancer accounts for about 13 percent of all new cancers. Those most at risk are older adults over the age of 50, and people who have a history of cigarette, cigar, or pipe smoking. According to the American Lung Association, 82 percent of those living with lung cancer in 2012 were 60 years of age or older. While tobacco smoke is the leading cause, people who have never smoked can develop lung cancer. This can be due to past lung infections, environmental factors, and genetic makeup.