Study Evaluating the Efficacy of Loco-regional Anaesthesia PECS on Chronic Pain of a Mastectomy

Inclusion Criteria: * Patients with unilateral breast cancer * Surgery must be a total mastectomy +/- axillary lymph node dissection and +/- reconstruction by prosthesis; unless first surgery was performed more than 5 years prior to total mastectomy without any residual pain * Age ≥ 18 ans * Non-opposition of patients Exclusion Criteria: * Reconstruction by other than prosthesis * Previous breast surgery in the last year * Hypersensitivity or allergy of anaesthetics * Coagulopathy and local infections * Pregnant or breastfeeding * Patients under guardianship