Inclusion Criteria:

- Age ≥ 50 years

- Smoking history ≥ 20 pack-years

- Subject undergoing diagnostic evaluation for a lung nodule

- Subject undergoing evaluation for a lung nodule by a pulmonologist, and/or by a
thoracic surgeon

- Baseline CT scan identifying lung nodule performed within 60 days of subject
enrollment

- Nodules identified by CT scan previously not followed

- Subject willing to provide informed consent for the collection of blood specimens

Exclusion Criteria:

- Nodule work-up at the time of enrollment eligibility indicates any prior attempted or
completed diagnostic biopsy procedure, such as transthoracic needle aspiration,
bronchoscopic biopsy or surgery

- A prior CT scan is available that previously identifies the same lung nodule under
consideration for study inclusion on the most current CT scan; AND the prior CT scan
was performed more than 60 days before the current CT scan, irrespective of the
candidate nodule's radiographic characterization such as size, density or appearance

- Current diagnosis of any cancer

- Prior diagnosis of any cancer within 2 years of lung nodule detection, except for
non-melanoma skin cancer

- Administration of blood products, e.g. packed red blood cells, fresh frozen plasma,
or platelets, within 30 days of subject enrollment

- History of human immunodeficiency virus (HIV) or Hepatitis C