A biopsy of a breast tumor lesion will be performed for processing to establish avatars (patient-derived organoids -PDO). A personalized tumorogram for each patient will be provided, based on the results of the drug screening (= tumor predicted as sensitive, intermediate, resistant or non-evaluable for each drug tested). Patients with an informative tumorogram will receive one of the recommended treatments (line N+1) in the event of tumor progression, administered according to standard procedures and validated at medical meetings specific to each center, and their fate will be monitored.