Oncologic safety of autologous fat grafting as part of local–regional management of breast cancer.

e12623 Background: Autologous fat grafting (AFG) is increasingly incorporated into breast reconstruction after mastectomy or breast-conserving surgery to improve contour and symmetry. Despite its widespread use, concerns remain regarding its potential impact on local and regional oncologic control, particularly in the setting of prior multimodal breast cancer treatment. We evaluated local and regional oncologic outcomes following AFG after surgical treatment of breast cancer. Methods: A retrospective single-center cohort study was performed including patients who underwent autologous fat grafting after surgical treatment for breast cancer between June 2023 and December 2024. Primary endpoints were local and regional oncologic events after the first AFG procedure. Secondary endpoints included distant progression and procedure-related complications. Associations between oncologic outcomes, nodal status, and number of AFG procedures were analyzed. Statistical analysis was conducted using StatTech v4.11.1; categorical variables were compared using χ² or Fisher’s exact test. A two-sided p value 0.05). Nodal status was associated with subsequent oncologic events (p = 0.008). Procedure-related complications (oleogranuloma or liponecrosis) were significantly associated with the number of AFG sessions (p < 0.001). Conclusions: In this single-center cohort, autologous fat grafting performed after breast cancer surgery was not associated with impaired local or regional oncologic control during short-term follow-up. Nodal status remained the primary factor associated with oncologic events, while an increased number of AFG procedures was linked to higher complication rates. These findings support the oncologic safety of AFG as part of breast reconstruction after surgical treatment of breast cancer, while highlighting the need for longer follow-up.