Interventional study with minimal risks and constraints, involving annual assessment of the prevalence and incidence of lung cancer using low-dose contrast-free thoracic CT scans, immunological, inflammatory, metabolic, blood nucleic acid and digestive microbiota profiles; systematic proposal of smoking cessation for active smokers, or assistance in maintaining cessation This is a prospective validation study of risk stratification tools still under development.

The results of this study will be used to design medical devices (software integrating risk stratification tools), which will then be evaluated as part of subsequent Clinical Investigations.

Inclusion Criteria:

Group A:

CI 1- Age > 18 years AND CI2a- Person eligible for screening with a nodule or lung mass with no indication of reassessment by CT scan before the next round of screening, as recommended by the multidisciplinary consultation meeting OR CI2b- Person not eligible for screening with a nodule or lung mass with an indication for reassessment by CT scan without immediate diagnostic workup (PET scan, biopsy, surgery) as determined by the multidisciplinary consultation meeting.

Group B CI1- Age > 18 years AND CI2- Indication for biopsy or surgical excision for diagnostic and therapeutic purposes proposed in a multidisciplinary consultation meeting.

Group C CI1a- Age 40 - 75 and daily smoking for at least 20 years initiated before age 15 OR CI1b- Age 50 - 75 and passive smoking for at least 20 years in a closed environment (family or workplace) OR CI1c- Age 50 - 75 and smoking 10 cig/d for 30 years or 15 cig/d for 25 years or 20 pack-years with no withdrawal period OR

CI1d- Age 50 - 75 and daily smoking for at least 10 years combined with at least one other lung cancer risk factor from among :

• Self-reported daily passive smoking for > 10 years (smokers at home or in enclosed environments)
• Self-reported exposure to a lung carcinogen: Radon, coal smoke, soot, diesel, nickel, beryllium, arsenic, cadmium, asbestos
• 1st-degree family history of lung cancer
• Personal history of tobacco-related disease, including atheromatous cardiovascular disease, COPD or emphysema, cancer not monitored by chest imaging
• weekly use of cannabis (joints) for 10 years

All Groups:

• Have signed an informed consent form
• Affiliated with or benefiting from a social security scheme
• Male or female

Exclusion Criteria:

Goups A and B Contraindication to lung biopsy or thoracic surgery for diagnostic or therapeutic purposes

Group C Eligible for lung cancer screening according to INCa* criteria

• Previous cancer < 5 years (except carcinoma in situ of the uterine cervix, basal cell carcinoma of the skin, non-invasive urothelial carcinoma treated for curative purposes without CT lung surveillance, prostate cancer with undiagnosable PSA)
• Symptoms of lung cancer (involuntary weight loss > 10% of usual weight in 1 year, hemoptysis)
• Known history of pulmonary nodule requiring specialized follow-up
• History of pulmonary fibrosis or pulmonary hypertension
• Active pulmonary parenchymal infection
• Severe cardiac or respiratory insufficiency (rest dyspnea)
• Performance status (WHO) 2, 3 or 4

All Groups

• patient privé de liberté
• patient sous tutelle ou curatelle
• femmes enceintes ou allaitantes
• patient dans l'incapacité d'effectuer le suivi de 30 mois