Abstract PS2-01-17: Long term outcome of patients having Breast Conserving Surgery and Immediate Lipofilling

Abstract Background: The impact of immediate lipofilling in the setting of breast conserving surgery on oncological outcomes are unknown. There is concern from in-vitro studies that adipose-derived stem cells may promote cancer recurrence through their proliferative properties. The aim of the present study was to investigate the long-term safety of breast conservation surgery (BCS) combined with immediate lipofilling. Methods: The patient cohort included 117 consecutive patients with invasive breast cancer or ductal carcinoma in situ (DCIS) who had BCS plus immediate lipofilling from 2011 to 2019 and 248 controls. Control patients had BCS without lipofilling in the same week as patients having BCS with lipofilling. Propensity score matching (PSM) was performed to determine the impact of immediate lipofilling on outcome where treatment (lipofilling) and control (no lipofilling) groups were matched for pathological and treatment variables. Multivariate survival analysis was performed to investigate the impact of lipofilling in subgroups according to T-stage, N-stage and tumour grade. The median follow up was 127 months. Results: There were 3 (2.5%) in-breast recurrences in lipofilled patients and 9 (3.6%) in the control group. When comparing lipofilled and non-lipofilled groups, there was no significant difference in overall survival (10-year, 94.8% vs. 93.3%; p=0.392), local recurrence (3.6% vs. 3.8%; p=0.601), regional recurrence (1.0% vs. 1.3%; p=0.761) and distant metastasis (5.8% vs. 3.3%; p=0.361). After propensity matching, lipofilling was not associated with mortality (log-rank, p=0.14), local recurrence (p=0.64), regional recurrence (p=0.91), or distant recurrence p=0.73). Across all pathological subgroups investigated, immediate lipofilling had no impact on overall survival or local recurrence (p>0.05). Conclusion: There is no evidence that immediate lipofilling performed at the same times as breast conserving surgery has any impact on mortality or on local, regional, systemic recurrence. This study shows the oncological safety of BCS plus immediate lipofilling. Citation Format: J. Lucocq, R. Swan, A. Klenjnotowska, J. Dixon. Long term outcome of patients having Breast Conserving Surgery and Immediate Lipofilling [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS2-01-17.