Background: Autologous fat grafting (AFG) is utilized for cosmetic improvement of the reconstructed breast following mastectomy. Fat necrosis (FN), a benign complication of AFG, can raise suspicion of malignancy and require further evaluation.
Objective: The aim of this study was to determine the incidence of FN in patients who have undergone AFG following mastectomy and reconstruction, and to identify factors contributing to FN.
Methods: A retrospective chart review was conducted of all patients who received AFG following mastectomy and reconstruction at our institution between 2011 and 2016, with a minimum 6-month follow-up period. Patient information, operative details, receipt of radiation, complications, and incidence of cancer recurrence were collected.
Results: A total of 171 patients were included in this study. AFG was performed by seven surgeons. Patients received an average of 1.18 treatments, with average follow-up of 26 months. Eighteen patients (10.5%) developed FN an average of 3.4 months following AFG. Patients with a larger volume injected at initial session (p = 0.044) and longer length of follow-up (p = 0.026) had significant increases in risk of developing FN. Core needle biopsy was performed in seven patients and two patients required excision. The rate of cancer recurrence was 1.7% for all patients and 0% in the AFG cohort.
Conclusions: Increased risk of FN following AFG is associated with greater volume injected at the initial session and higher incidence over time. Although AFG is oncologically safe, patients should be counseled on the 10.5% incidence of FN presenting as a palpable abnormality, and the approximately 5% chance of requiring biopsy or excision.