Lung and bronchus cancers account for almost 13% of new cancer cases and are responsible for approximately 23% of cancer deaths in the United States. Lung cancer has a poor prognosis, primarily because of advanced disease stage at initial diagnosis. An estimated 80% to 90% of lung cancer deaths are caused by smoking tobacco, and although smoking rates have decreased in recent decades, millions of people are eligible for lung cancer screening each year because they smoke. Screening high-risk populations for lung cancer using low-dose computed tomography has resulted in increased lung cancer survival rates because diagnosis is possible at an earlier disease stage.