Lung Cancer Screening Program Using Low-dose Tomography and Metabolomic Evaluation in a Public Service.

This study is testing a lung cancer screening program using low-dose CT scans (a type of chest X-ray that uses less radiation) along with blood tests to look for early signs of lung cancer in people who are or were heavy smokers. **You may be eligible if...** - You are between 45 and 74 years old - You are a current smoker with at least 30 pack-years of smoking history, or a former smoker who quit less than 15 years ago - You have never participated in a lung cancer screening program before **You may NOT be eligible if...** - You have an advanced chronic disease (heart, lung, liver, kidney, or metabolic) that limits life expectancy or ability to have surgery - You are being treated for tuberculosis or a similar granulomatous disease - You have a history of cancer that could spread to the lungs - You are pregnant - You are unable to undergo a chest CT scan Talk to your doctor to see if this trial is right for you.