Inclusion Criteria:

• Subject aged 50-80 years at time of consent.
• Increased risk of lung cancer defined by having at least 20 pack-year smoking history and currently smoke or have quit within the past 15 years.
• Undergoing or intended to undergo low dose CT scan of the chest for lung cancer screening.
• Willing to consent to the investigational blood draw during index low dose CT scan screening visit and before any invasive procedures or treatment for lung cancer diagnosis.
• Willing to consent to a 1-year, 2-year and additional follow-up per protocol.

Exclusion Criteria:

• Subject has not smoked for 15 or more years.
• Subject has less than 20 pack-year smoking history.
• Subject has a health problem that substantially limits life expectancy and/or the ability or willingness to have curative lung surgery.
• Subject undergoing low-dose CT scan of the chest for investigation of symptoms suspicious for lung cancer.
• Preexisting or history of lung cancer.
• Previously diagnosed high-risk lung lesion.
• 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).
• Currently taking any anti-neoplastic or disease-modifying anti-rheumatic drugs.
• Currently receiving treatment for pneumonia.
• 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.
• Known medical condition which, in the opinion of the investigator, should preclude enrollment into the study.
• 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.
• Additional cohorts: inclusion and exclusion criteria will be specified for each cohort as appendixes.

Eligibility last updated 1/21/22. Questions regarding updates should be directed to the study team contact.