This study is part of the development and validation of a non-invasive lung screening test which aim to identify early stage lung cancer in patients at high risk for lung cancer.

This is a prospective, case-control, multi-center, observational nonsignificant risk study. The study aims to collect blood and clinical data from subjects undergoing Low Dose CT (LDCT) for lung cancer screening and subjects with confirmed lung cancer.

Inclusion Criteria - Cases:

• Current or past smokers, with at least 20 pack-years
• Subjects with either A high suspicion for lung cancer, with planned surgery to establish a definitive diagnosis within 60 days after date of blood collection OR treatment naive lung cancer patients

Exclusion Criteria - Cases:

• Known diagnosis or treatment of any previous cancer, including lung cancer, in the past 5 years, except for fully resected non-melanoma skin cancer or fully-resected carcinoma in situ of the cervix
• Current lung cancer is known to be stage III or IV by pathology.

Inclusion Criteria - Screening:

- Current or past smokers, with at least 20 pack-years, undergoing LDCT for lung cancer screening

Exclusion Criteria - Screening:

• Known diagnosis or treatment of any cancer, including lung cancer, in the past 5 years, except for fully resected non-melanoma skin cancer or fully-resected carcinoma in situ of the cervix
• Subjects whose purpose of performing LDCT is for surveillance of a lung nodule

The Case Series will include subjects 50-80 years old, current or past smokers with at least 20 pack-years, with either (a) a high suspicion for lung cancer, who are planning to undergo surgery to establish a definitive diagnosis; or (b) confirmed lung cancer diagnosis, however did not yet undergo any treatment for this cancerous lesion.

The Screening Series will include subjects 50-80 years old, current or past smokers, with at least 20 pack-years, undergoing LDCT for lung cancer screening.

All subjects should be without other cancer in the past 5 years except for fully resected non-melanoma skin cancer or fully-resected carcinoma in situ of the cervix