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

Immediate reconstruction after mastectomy may help women with breast cancer to deal with their fear of mastectomy, spare them one or more second surgery and additional hospital stays in case of late breast reconstruction. However, in France, most patients with invasive breast carcinoma and treated with mastectomy are not offered immediate reconstruction. One reason is the need for postoperative radiotherapy for most patients (40 to 70% according to the centers). Indeed, radiotherapy induces side-effects which can alter the cosmetic result of the breast reconstruction as well as the patient's quality of life. Since 1995, a significant correlation is observed between the RILA test (measurement by flux cytometry of the lymphocyte T-CD8 apoptosis induced by radiotherapy) and the risk of occurrence of severe radio-induced breast fibrosis. Such accurate personalized medical care could allow identifying before any treatment high risk of toxicity patients and thus help establishing the therapeutic strategy. Identification of low-risk patients could also allow limiting autologous samplings and thus their associated morbidity.

Inclusion criteria

• Age ≥18 years
• Patients with histologically 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

Exclusion criteria

• 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 informed consent
• Participation in an interventional clinical study or planned participation during study up to 12 months post-radiotherapy