Oncologic Outcome of 1000 Postmastectomy Breast Reconstructions with Fat Transfer: A Single-Center, Matched Case-Control Study

Background: Autologous fat transfer has an important role in breast reconstructive surgery. Nevertheless, some concerns remain with regard to its oncologic safety. The authors present a single-center, case-matching study analyzing the impact of autologous fat transfer in the cumulative incidence of local recurrences. Methods: From a prospectively maintained database, the authors identified 902 patients who underwent 1025 breast reconstructions from 2005 to 2017. Data regarding demographics, tumor characteristics, surgery details, and follow-up were collected. Exclusion criteria were patients with distant metastases at diagnosis, recurrent tumor, or incomplete data regarding primary tumor; and patients who underwent prophylactic mastectomies and breast-conserving operations. Statistical analysis was conducted to evaluate the impact of the variables on the incidence of local recurrence. A value of p < 0.05 was considered statistically significant. Results: After 1:n case-matching, we selected 919 breasts, of which 425 patients (46.2 percent) received at least one autologous fat transfer session versus 494 control cases (53.8 percent). Local recurrences had an overall rate of 6.8 percent, and we found local recurrences in 14 autologous fat transfer cases (3.0 percent) and 54 controls (9.6 percent). Statistical analysis showed that autologous fat transfer did not increase the risk of local recurrences (hazard ratio, 0.337; CI, 0.173 to 0.658; p = 0.00007). Multivariate analysis identified invasive ductal carcinoma subtype and lymph node metastases to have an increased risk of local recurrences (hazard ratio >1). Conversely, positive hormonal receptor status was associated with a reduced risk of events (hazard ratio <1). Conclusions: Autologous fat transfer was not associated with a higher probability of locoregional recurrence in patients undergoing breast reconstruction; therefore, it can be safely used for total breast reconstruction or aesthetic refinements. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.