A study presented at the 2013 ASCO Annual Meeting found that lung cancer screening using low-dose CT scans reduced lung cancer mortality by 20% compared to chest X-rays. Researchers conducted a randomized controlled trial of over 53,000 participants aged 55-74 who were either current or former heavy smokers. Those in the low-dose CT screening group received three annual screenings, while the chest X-ray group received three screenings over 6 years. The results provide evidence that lung cancer screening with low-dose CT scans saves lives when used to screen those at high risk for lung cancer.