Immediate Autologous Tissue Breast Reconstruction and Radiotherapy Strategy After Breast Cancer Surgery

This is a prospective, open-label, controlled clinical trial aiming to investigate the optimal sequencing strategy between immediate autologous tissue breast reconstruction and radiotherapy in breast cancer patients. Eligible participants are female breast cancer patients who have completed neoadjuvant chemotherapy and are scheduled to undergo total mastectomy combined with immediate free abdominal flap (DIEP) breast reconstruction. Participants will be assigned to receive either preoperative radiotherapy followed by reconstruction, or postoperative adjuvant radiotherapy after reconstruction. The primary objectives are to compare surgical safety, oncological safety, patient-reported outcomes (PRO), and aesthetic evaluation between the two radiotherapy sequencing strategies. Secondary objectives include optimizing radiotherapy techniques, radiation doses, and target volume delineation for immediate abdominal free flap reconstruction; exploring the impact of hypofractionated radiotherapy on reconstruction-related complications; investigating the association between multi-omics and immune microenvironment changes and radiotherapy efficacy; and exploring the mechanism by which skin microbiota characteristics affect radiation-induced skin injury through modulation of the skin immune microenvironment. This study hopes to provide clinical evidence for establishing the optimal treatment sequence of immediate breast reconstruction and radiotherapy.