Polyurethan Versus Non-polyurethan Covered Implants in Combination With Radiotherapy

Inclusion Criteria: * Patients with signed General consent or study specific consent form * Patients with confirmed diagnosis of primary or recurrent breast cancer * Patients undergoing nipple - or skin-sparing mastectomy with prepectoral IBBR (all types of implants, with or without mesh, all types of biologic and synthetic mesh, one- or two- stage) in the setting of PMRT (or any type or RT before reconstruction) between 2016 and 2022. * Patients undergoing two-stage IBBR with radiotherapy to the expander before reconstruction with implant. * Patients with recurrent breast cancer after breast conserving surgery and radiotherapy. * Follow up must be at least 2 years after IBBR. * Patients aged 18 and above will be eligible for inclusion. Exclusion Criteria: * Patients who have explicitly refused the further use of their data through a consent declaration. * Patients undergoing subpectoral IBBR or autologous reconstruction as initial type of reconstruction. * No radiotherapy.