Prospective Multicentre Study for the Application of Telomere Measurement Technology as a Tool for Lung Cancer Diagnosis

Inclusion Criteria:

Case Group:

* Person aged 45 years or older at the time of signing the consent form.
* Person with a current anatomopathologically confirmed diagnosis of small-cell or non-small cell lung cancer.
* Not having received any oncological treatment prior to sample collection (surgery, radiotherapy, or systemic treatment with chemotherapy or immunotherapy).

Control Group:

Cohort A (High risk controls):

* Person aged 45 years or older at the time of signing the consent form.
* High risk of lung cancer, defined as having a smoking history of at least 20 pack-year and currently smoking or having quit within the past 15 years.
* No diagnosis or suspicion of lung cancer. Asymptomatic individuals who have undergone a chest computed tomography (CT) scan for lung cancer screening within the 12 months prior to signing the informed consent and as part of routine clinical practice, with a LUNG-RADS score of 3 or lower, will be included.

Cohort B (Low-risk controls):

* Person aged 45 years or older at the time of signing the consent form.
* Without high risk of lung cancer according to the criteria defined in cohort A.
* No diagnosis or suspicion of lung cancer.

Exclusion Criteria:

* History of any malignant neoplasm, except for subjects with tumors in localized stages who have undergone radical treatment and have been disease-free for at least five years.
* Patient diagnosed with lung cancer who has already started oncological treatment before sample collection.
* Patient who has undergone a biopsy or any invasive procedure or minor surgery less than 48 hours ago.
* Patient who has undergone major surgery less than 7 days ago.
* Patient with severe chronic kidney disease, defined as a glomerular filtration rate below 15 ml/min.
* Patient with severe liver disease, defined as Child-Pugh C.
* Active infection, or treated less than 4 weeks ago.
* Vulnerable population, for example, minors, prisoners, pregnant women, adults physically or mentally incapable of giving consent.