Patients who have had curative treatment for lung cancer are at an increased risk of developing second primary lung cancers (and other cancers) over the next 10 years. Doctors need to develop better ways of monitoring patients during follow up so we can intervene as quickly as possible with further treatments. Measuring DNA in the blood which has come from the tumour, so called circulating tumour DNA (ctDNA), may be one way to do this.

This is a multi-centre, observational basic science study to follow patient who have undergone radical treatment, surgery or radiotherapy for Non-small Cell Lung Cancer (NSCLC) between two and five years previously. Following consent, participants will be asked to provide blood samples every six months for up to the next five years. Information from their routine clinical care, including information from any imaging, diagnostic tissue samples and blood tests will be collected. We will also request access to any original surplus diagnostic material, as well as future, excess tissue from diagnostic samples.

Blood samples will be analysed using various new scientific techniques looking to correlate emergence of new primary cancer (or recurrence of original NSCLC) with blood based markers.

Inclusion Criteria:

• previous treatment with curative intent (surgery or radical (chemo)radiotherapy) for stage I-IIIA primary NSCLC
• at least two years post first treatment date of first primary NSCLC
• able to provide informed consent

Exclusion Criteria:

• Primary lung tumour was a carcinoid tumour
• in the opinion of the managing clinician, thought unlikely to survive 12 months from time of potential recruitment.

Patients who have been treated with curative intent (surgery/(chemo)radiotherapy) for stage I to IIIA Non-small cell carcinoma, between two and five years ago.

The only clinical data available to researchers will be anonymised. Permission will be sought at consent to retain data sets for up to 15 years at the end of the study to use for this study or other ethically approved studies.