Evaluation of Somatostatin Receptor Expression in PET 68Ga-DOTATOC in Patients Followed for Metastatic Breast Cancer

Inclusion Criteria: * Age over 18 * Patients with metastatic breast cancer who have completed at least one first line of systemic therapy for metastatic breast cancer * Patient labeled on the primary lesion ER+HER2- (20) * Presence of metastatic liver and bone lesions identifiable with 18F-FDG PET-Scan * Presence of at least 10 identifiable secondary lesions in 18F-FDG PET-Scan * No therapeutic change between 18F-FDG PET-Scan and 68Ga-DOTATOC PET-Scan. * Performing the PET scan with 68Ga-DOTATOC within a maximum of 21 days after the 18F-FDG PET-Scan * Person affiliated to or benefiting from social security * Person who has given written informed consent Exclusion Criteria: * Patients followed or with history of other active neoplastic pathology (including neuroendocrine tumor) * Known allergy to 68Ga-DOTATOC or its excipients * Subject refusing to sign the consent to participate * Minor subject * Subject excluded from another study * Persons referred to Articles L1121-5 to L1121-8 of the Public Health Code (CSP) * Subject cannot be contacted in case of emergency