The objective is to study the phenotypic, functional and metabolomic characteristics of neutrophils circulating subpopulations in lung cancer patients, and to compare them to a control group of healthy volunteers. A blood sample will be taken before the first treatment session for the lung cancer patient and a second blood sample will be taken during the first evaluation visit.

The investigators hypothesize that there may be different circulating neutrophil subpopulations in patients with metastatic non-small cell lung cancer (NSCLC) involved in tumor progression and resistance to immunotherapy.

Immune checkpoint inhibitors (ICI) have been shown to be effective in metastatic lung cancer. Unfortunately, 80% of patients do not respond and show rapid disease progression. Identifying predictive biomarkers of response is essential for early adaptation of management. Circulating lymphocytes and neutrophils represent a biomarker (NLR), predictive of immunotherapy response, in particular via the measurement of the neutrophils /lymphocyte ratio. Some preclinical work suggests a role for circulating neutrophil subpopulations like MDSC (myeloid derived suppressor cells) in ICI resistance. Certain circulating neutrophil subpopulations are thought to promote tumor progression, angiogenesis and metastasis with immunosuppressive activity. Identifying these pro-tumor subpopulations could predict the response to ICI and could be a potential therapeutic target. Our goal is to characterize the circulating neutrophil subpopulations of lung cancer patients and correlate these characteristics with response and survival phenotypically and functionally.

Inclusion Criteria common to lung cancer and COPD patients :

• Age ≥ 18 years,
• male or female,
• affiliated with a Health Insurance,

Inclusion Criteria for lung cancer patients :

- Diagnosis of metastatic stage lung cancer with mutation status, naïve treatment

Inclusion Criteria for COPD patients :

- Diagnosis of COPD post-smoking

Exclusion Criteria:

• Tuberculosis or other acute or chronic bacterial infections
• Chronic progressive viral infections (Hepatitis B and C, HIV)
• Previous or ongoing chemotherapy
• Impossibility of giving the subject informed information.
• Opposition to the research.
• Participation in another research study with an exclusion period still in progress at pre-inclusion (possible inclusion in an observational study)
• Vulnerable individual (pregnant, parturient or breastfeeding woman), persons under guardianship or curatorship, or deprived of liberty by a judicial or administrative decision)
• Patients benefiting from the AME

Patients with metastatic lung cancer, without anterior treatment. Inclusion during a consultation or hospitalization by a pneumologist or oncologist in the thoracic oncology unit during care.