Reconstructive surgery with breast implants after total mastectomy for breast cancer is invariably related to several possible complications, such as atrophy of surrounding tissues, skin thinning, capsular contracture, wound dehiscence and inframammary fold break. Such complications are promoted by elastic properties of tissues and their response to gravity forces exerted on breast implant weight, leading to microischaemic events. A poor cosmetic outcome may result up to breast implant exposure, and its removal may become necessary, thus compromising the quality of breast reconstruction. These complications are further favoured by post-mastectomy radiotherapy (PMRT), since irradiation could enhance microischaemia of peri-prosthetic soft tissues and muscle, with subsequent inadequate healing, fibrosis and thinning. Since PMRT has been associated to improved loco-regional control in node-positive breast cancer patients, its use has increased in recent years. On one hand, PMRT has improved loco-regional control but, on the other hand, it has increased the failure rate of breast reconstruction after total mastectomy. Change of timing in breast reconstruction (immediate vs. two-staged by use of tissue expander) has not decreased the complications rate after PMRT. Currently the failure rate of breast reconstruction after total mastectomy and PMRT ranges from 0% to 40%. The present study will recruit 80 participants affected by breast cancer candidated to total mastectomy with immediate breast reconstruction and subsequent PMRT or total mastectomy with reconstruction by tissue expander, subsequent PMRT and then definitive reconstruction with breast implant. Participants will be randomized in two experimental arms: 40 patients will receive final reconstruction by the use of standard silicone-based breast implant and the other 40 patients will receive B-Lite® light weight breast implant. Participants will be followed up at 1, 6, 12 and 24 months, and all patients will undergo breast MRI at 6 months. The primary goal of the present study is to evaluate the failure rate of breast reconstruction (i.e. the need of re-intervention for breast implant removal). Secondary end-points include the overall complications rate, MRI evaluation of breast implant and surrounding tissues, cosmetic outcomes and quality of life including participants' satisfaction with breast reconstruction.

Inclusion Criteria:

• Breast cancer diagnosis with indication of total mastectomy and breast reconstruction
• Indication of post-mastectomy radiation therapy
• Availability to be followed up for 24 months
• Signature of informed consent

Exclusion Criteria:

• Patients candidated to breast-conserving surgery
• Contraindicated breast reconstruction (severe comorbidities, unfavourable survival outcome expected, distant metastases)
• Patients affected by other solid malignancies
• Pregnancy
• Participation to other clinical studies in the last three months