Inclusion Criteria:  Age> 18 years old Man or woman Diagnosis of locally advanced non-small cell bronchial adenocarcinoma (not eligible for locoregional treatment) or metastatic Tumor with an activating mutation of EGF-R (deletion of exon 19 or L858R, L861x, or G719x mutation) No one opposed to his participation in the research Dated and signed consent form Patient in good general condition according to WHO (PS: 0 or 1)  Exclusion Criteria:  Previous treatment of NSCLC with an EGF-R tyrosine kinase inhibitor Adult persons subject to legal protection (safeguard of justice, curatorship, guardianship), persons deprived of their liberty. Treatment with Osimertinib on going Co-treatments with a potent enzyme inducing or inhibitor compound within 2 weeks before starting treatment with Osimertinib Participation in intervention research on a drug