MIRs 04 : Interpectoral Nerve Block With Ropivacaine Versus Placebo Before Breast Cancer Surgery

Inclusion Criteria: 1. Women with non-metastatic invasive breast carcinoma or breast carcinoma in situ treated by breast-conserving surgery (tumorectomy) with sentinel node technique on one day surgery. 2. Age between 18 and 85 years. 3. ASA class 1, 2 or 3 4. Signed informed consent form. Exclusion Criteria: 1. Ongoing neoplasm or history of neoplasm other than breast cancer with the exception of: basal cell carcinoma, cervical carcinoma in situ, other treated cancer that has not relapsed during the 5 years preceding inclusion in the trial. 2. Axillary dissection planned during surgery planning 3. All bilateral surgery the day of Pecs administration 4. Metastatic breast carcinoma at diagnosis (M1). 5. Allergy to local anesthetics and morphine. 6. Use of analgesics during the 12 hours preceding the surgical procedure. 7. History of ipsilateral surgery during the previous 6 months. 8. History of substance abuse. 9. Pregnant woman or breastfeeding. 10. Subjects deprived of their liberty or under guardianship (including temporary guardianship). 11. Subjects no covered by social security scheme 12. Experiencing any psychiatric condition or major cognitive impairment that may hamper completion of self-reported questionnaires. There is no prohibition for people to take part simultaneously in another search and there is no exclusion cause at the end of the research period