Oncologic Safety and Surveillance of Autologous Fat Grafting Following Breast Conservation Therapy: A Matched Control Study

Abstract

BACKGROUND: Autologous fat grafting (AFG) has become an increasingly popular adjunct following breast reconstruction. The impact of AFG on oncologic safety and surveillance remains questionable in breast conservation therapy (BCT). The purpose of this retrospective study was to compare oncologic outcomes of delayed AFG in the setting of BCT (lumpectomy with radiation) to a matched cohort of BCT patients not reconstructed with AFG. METHODS: The authors retrospectively reviewed a prospectively maintained database for patients who underwent delayed AFG following BCT between 2006 and 2016. A control group of patients with BCT, but not AFG, was identified with similar cancer stage, age, body mass index, and length of follow-up. All patients had follow-up visits and imaging at regular intervals at our institution. The primary outcome of interest was locoregional recurrence (LRR). Secondary outcomes included postoperative complications such as palpable mass, fat necrosis, calcifications, and oncologic surveillance. RESULTS: Seventy-two patients were identified per cohort (BCT versus BCT + AFG). There were no differences in median age (50 versus 51 years; P = 0.87), body mass index (28.2 versus 27.2 kg/m2; P = 0.38), or length of follow-up (61.9 versus 66.8 months; P = 0.144) between BCT and BCT + AFG patients, respectively. Overall, 4 patients in each cohort experienced LRR (5.6%; P = 1.00) with similar cumulative incidence estimates observed (log-rank test P = 0.534). There were no significant differences in postoperative palpable mass (9.7% versus 19.4; P = 0.1), fat necrosis (34.7% versus 33.3%; P = 0.86), calcifications on mammogram (37.5% versus 34.7%; P = 0.73), or indication for breast biopsy (15.3 versus 22.2; P = 0.23) between BCT and BCT + AFG cohorts, respectively. CONCLUSIONS: Overall, we found no differences in LRR in BCT patients with or without delayed AFG. Furthermore, there was no difference in the rates of fat necrosis, palpable mass, and abnormal radiographic findings. Biopsy rates were similar between the groups. This study represents the largest matched comparative cohort of AFG in BCT demonstrating oncologic safety and no interference with follow-up surveillance.