Abstract: Objective  To investigate the methods and therapeutic efficacy of autologous flap transplantation for reconstructing massive thoracic wall defects following radical resection of locally advanced breast cancer. Methods  A retrospective analysis was conducted on 29 breast cancer patients treated between January 2017 and November 2023. All patients underwent neoadjuvant therapy followed by extended tumor resection and autologous flap reconstruction. Surgical parameters and prognostic outcomes were evaluated. Results The patients， aged 41-58（ mean 48.2±8.1） years， included 19 cases of invasive ductal carcinoma， 5 fibroepithelial tumors， 3 adenocarcinomas， and 2 encapsulated breast cancers. Molecular subtypes comprised Luminal A（ 14 cases）， Luminal B（ 7 cases）， HER-2 overexpression（ 3 cases）， and basallike（ 5 cases）. Key outcomes included a mean hospital stay of（ 13.8±5.2） days， operative duration of（ 4.6±1.6） hours， and intraoperative blood loss of（ 298.3±94.7） mL. Tumor sizes ranged from 6 cm×11 cm to 26 cm×19 cm， with flap dimensions spanning 13 cm×7 cm to 22 cm×29 cm. Flap types included local flaps（ 18 cases）， pedicled latissimus dorsi myocutaneous flaps （9 cases）， transverse rectus abdominis myocutaneous （TRAM） flap （1 case）， and free deep inferior epigastric perforator （DIEP） flap （1 case）. There were 8 cases with combined sternum or rib defects. Among them， 7 cases did not require titanium mesh repair， and 1 case used titanium mesh to reconstruct the chest wall. Of the 29 patients， 27 had normal chest wall function， 1 had necrosis of autologous flap， and 1 had blood supply disorder of autologous flap. The necrotic flap healed after secondary debridement and suture. The median follow-up time for 29 patients after the operation was 39 months. The 3-year local recurrence rate and overall survival rate were 65.6% and 34.4%， respectively. Conclusion Autologous flap reconstruction after neoadjuvant therapy and extended resection effectively restores thoracic wall function and enhances quality of life in locally advanced breast cancer patients.

Key words: Breast neoplasm, &emsp, Autologous flap, &emsp, Chest wall reconstruction, &emsp, Locally advanced breast cancer