Postoperative pneumonia is one of the most common complications after lung cancer surgery and associated with a morbidity and mortality. Postoperative lymphopenia has been recently identified as one of risk factors for postoperative pneumonia. According to recent studies in polytrauma, cancer or septic shock, T cells dysfunction may be related to high expression of inhibitory receptors on lymphocytes.

This study will investigate prospectively TIM-3, PD-1 and CTLA4 expression on lymphocytes T cells before and after lung cancer surgery. Patients ≥ 18 years with no history of immunosuppressive state will be included.

Inclusion Criteria:

• Patient ≥ 18 years undergoing lung cancer surgery by thoracoscopy

Exclusion Criteria:

• Patient under guardianship/curatorship
• Patient who received of radiotherapy or chemotherapy in the last 6 months
• Patient under immunosuppressive treatment or dose of corticoids over 10 mg/day prednisolone or equivalent
• Patient with history of malignant blood disease or auto-immune disease
• Patient suffering from HIV infection and
• Patients with pre-operative infection
• Patient with an empiric antibiotic therapy introduced at operating room