Preliminary data on the oncological safety of autologous fat transfer (AFT) for total breast reconstruction from the BREAST trial.

Abstract

Total breast reconstruction via autologous fat transfer (AFT) improves the quality of life compared to implant-based reconstruction (IBR). Hypotheses are that AFT may affect oncologic outcomes. As predetermined in the study protocol, we present the loco-regional recurrence data from the BREAST trial. This prospective cohort study is based on participants from the BREAST trial, comparing AFT to IBR after mastectomy. Patients were randomised 1:1 to AFT or IBR. Oncological follow-up, including clinical exams and imaging, was conducted annually for five years post-reconstruction in the intervention group. Data on demographics, tumour characteristics, and treatment details of the first tumour were collected from medical records and national pathology databases. Primary outcome for analysis was loco-regional breast cancer recurrence (LRR). In total, 77 patients were included in the AFT arm and 86 in the control arm. Time from breast cancer diagnosis to first AFT exposure was considered control time to minimise immortal time bias. Eight patients in the AFT group and 5 in the control group experienced loco-regional recurrence. This was not significantly different (hazard ratio 1.74 (95% CI: 0.56 - 5.44, p = 0.341) in comparison to control. After adjustment for confounders, the difference remained non-significant. Per study protocol, loco-regional recurrence in the BREAST trial was analysed: no significant difference was observed between AFT-reconstruction and IBR-reconstruction. This study was underpowered for oncological endpoints, the population was too heterogeneous, and not all participants received recommended oncological care.