A prospective, observational, single-center study to determine the proportion of patients who have or will develop changes in biological markers of immunity during immunotherapy treatment.

The study will run for 12 months with a 6-month follow-up at the inclusion of the last patient.

Patients will be included from the initiation of immunotherapy treatment regardless of the line.The routine immunological workup will be performed before the first immunotherapy infusion in order to analyze a certain number of immunological markers (autoantibodies, RF, LDH, complement (C3 C4), anti-tissue antibodies, lymphocyte immunophenotyping). This assessment will then be performed at progression, at the appearance of side effects requiring the immunotherapy to be stopped, or at 6 months of follow-up in case of continuation of the immunotherapy.

The investigators will evaluate the response to the treatment, the progression via re-evaluation assessments performed in standard practice (every 3 to 4 courses depending on the type of immunotherapy) as well as the appearance of side effects throughout the follow-up will be evaluate.

Inclusion Criteria:

• Major patient
• Metastatic non-small cell lung cancer
• Initiation of anti PDL1 therapy (NIVOLUMAB, PEMBROLIZUMAB or ATEZOLIZUAMB) in daily practice
• No objection made

Exclusion Criteria:

• Autoimmune disease diagnosed prior to initiation of immune checkpoint inhibitor therapy.
• Previous immune-modulating therapy (including corticosteroid therapy greater than 10 mg/day)
• Patient with prior checkpoint inhibitor therapy
• Patient with a contraindication to immunotherapy
• Patient under legal protection
• Refusal to participate

Patients with metastatic non-small cell lung cancer receiving immunotherapy (NIVOLUMAB, PEMBROLIZUMAB or ATEZOLIZUMAB) regardless of the line of treatment in daily practice

All collected data that underlie results in a publication

Data will be available beginning 18 months and ending five years following the publication

Data access requests will be reviewed by the internal committee of Brest UH. Requestors will be required to sign and complete a data access agreement.