This study aims to

1. Identify biomarkers and signatures to differentiate between high-risk and lung cancer patients.
2. Discover blood-based biomarkers that can be used as an adjunct test to imaging diagnosis to improve patient follow-up.

With existing evidence showing the utility of using liquid biopsy for early cancer detection, the investigators hypothesized that cell-free DNA and/or RNA expression changes during disease progression, and biomarker signature can be derived from the changes in expression levels. The investigators aim to discover and validate RNA and methylated cell-free DNA cancer biomarkers that can discriminate between high-risk and lung cancer patients.

Inclusion Criteria:

• Male or female subjects aged 30 and above.
• No previous history of any cancers.
• Able to provide X-ray and/or LDCT results.
• Have either COPD or pulmonary nodules measuring less than 11mm, or deemed not for biopsy by attending physician
• Willing to go back for a follow-up X-ray or LDCT scan in the next clinical follow up as per standard of care.
• Willing to provide up to 30mL of blood in month-0 (first visit) and up to 21mL in the next standard of care follow up visit (second visit).

Exclusion Criteria:

• Subject has received chemotherapy or radiotherapy for cancer treatment, and any other cancer-related treatment.
• Subject is pregnant or lactating (self-declaration).
• Subject is unwilling or unable to provide signed informed consent

Cohort A Subjects in this cohort are recruited if they have either of the following: pre-existing chronic obstructive pulmonary disease (COPD) or are found to have lung nodules smaller than 11mm, or nodules that are deemed not for biopsy by the attending physician.

Cohort B Subjects in this cohort are highly suspicious of having lung cancer. From the results of the X-ray or LDCT imaging, the subject would have nodules larger than 11mm, or show signs of lung cancer.