Predictive Toxicity Test Linked to Radiotherapy After Mastectomy and Immediate Implant Reconstruction

Who May Qualify: - Age ≥18 years - Patients with diagnosed by tissue sample (biopsy-confirmed) breast cancer with indication of mastectomy or surgery with mastectomy performed - Indication of wall chest radiation after mastectomy - Patient's agreement to receive or having had an immediate breast reconstruction by implant in one or two steps, with or without a dermal or synthetic matrix (depending on the habits of the center) - Performance Status 0-1 - Consent signed before any study procedure - Patient geographically accessible for follow-up - Affiliated to the French national social security system Who Should NOT Join This Trial: - Breast reconstruction with flap - Inflammatory breast cancer (cT4d) - Skin or parietal breast cancer (cT4 a, b or c) - Metastatic patients - Patients with bilateral breast cancer - History of homolateral breast cancer treated with radiotherapy - History of contralateral breast cancer - Pregnant or breastfeeding women - Legal incapacity or physical, psychological or mental status interfering with the patient's ability to sign the willing to sign a consent form - Participation in an interventional clinical study or planned participation during study up to 12 months post-radiotherapy Always talk to your doctor about whether this trial is right for you.