Validation of the SPOT-MAS Lung Test Using Circulating Tumor DNA for the Detection of Lung Cancer

Inclusion Criteria: Cohort A 1. Volunteers (participants) aged 50-80 years at the time of consent. 1. 50% smokers with a smoking history of 20 pack-years who currently smoke or have quit within the past 15 years. 2. 50% never-smokers or light smokers (\< 20 pack-years or quit \> 15 years) who are first- or second-degree relatives of LC patients. 2. Willing to undergo LDCT/NCCT of the chest for lung cancer screening. 3. Willing to consent to an investigational blood draw during the index LDCT/NCCT screening visit and before any invasive procedures or treatment for lung cancer diagnosis. 4. Willing to consent to a 1-year follow-up and additional follow-ups as per protocol. Cohort B 1. Subjects aged 50-80 years at the time of consent. 1. 50% smokers with a smoking history of 20 pack-years who currently smoke or have quit within the past 15 years. 2. 50% never-smokers or light smokers (\< 20 pack-years or quit \> 15 years) who are first- or second-degree relatives of LC patients. 2. Have undergone LDCT/NCCT of the chest for lung cancer screening/diagnosis, including only high-risk lesions (LUNG-RADS 4). 3. Willing to consent to an investigational blood draw before any invasive procedures (CECT/PET-CT/biopsy) or treatment for lung cancer diagnosis. 4. Willing to consent to a 1-year follow-up and additional follow-ups as per protocol. Exclusion Criteria for both Cohort A and Cohort B 1. Subject has a health problem that substantially limits life expectancy and/or the ability or willingness to have curative lung surgery. 2. Subject is undergoing CECT for investigation of highly suspicious symptoms for lung cancer. 3. Pre-existing or history of lung cancer. 4. History of any malignancy (subjects who have undergone surgical removal of skin squamous cell cancer may be enrolled provided the procedure was completed at least 12 months prior to the date of provision of informed consent for the study). 5. Currently taking any anti-neoplastic or disease-modifying anti-rheumatic drugs. 6. Currently receiving treatment for pneumonia. 7. Any major physical trauma (e.g., disruption of tissue, surgery, organ transplant, blood product transfusion) within the 30 days leading up to the provision of informed consent. 8. Known medical condition which, in the opinion of the investigator, should preclude enrollment into the study. 9. Participation in a clinical research study in which an experimental medication and/or medical procedure has been administered or may be administered within the 30 days leading up to providing informed consent or may be administered through the time of subject screening. \- Exclusion Criteria: \-