Abstract
BACKGROUND: Adipose-derived stem cell (ADSC)-enhanced fat grafting may improve graft retention and aesthetic outcomes in breast reconstruction, but its safety and efficacy remain uncertain. This systematic review and meta-analysis compared ADSC-enhanced with conventional fat grafting using rigorous methodology and predefined subgroup analyses. METHODS: The authors searched 6 databases for comparative studies published from January of 2000 through November of 2024. Random-effects meta-analyses were used to assess outcomes, with subgroups defined by ADSC preparation method, follow-up duration, and reconstruction indication. RESULTS: Thirty-one studies (1426 patients: 634 ADSC-enhanced, 792 conventional) met inclusion criteria. ADSC-enhanced grafting significantly improved fat retention (mean difference [MD], 26.8% [95% CI, 18.2 to 35.5]; P < 0.001; moderate-certainty evidence). Ex vivo-expanded ADSCs achieved the greatest improvement (MD, 64.6% [95% CI, 60.5 to 68.7]); stromal vascular fraction methods provided moderate gains (MD, 17.0% [95% CI, 8.6 to 25.4]; P < 0.001; I² = 78%). Complication rates were similar between groups (18.4% versus 17.2%; risk ratio, 1.07 [95% CI, 0.65 to 1.77]; P = 0.78). Among 813 patients with previous breast cancer, recurrence rates did not differ significantly (5.3% versus 3.4%; risk ratio, 1.56 [95% CI, 0.10 to 24.3]; P = 0.75). Patient-reported and aesthetic outcomes generally favored ADSC-enhanced grafting. CONCLUSIONS: ADSC-enhanced fat grafting increases graft retention without raising complication or recurrence risk. Ex vivo-expanded ADSCs offer the greatest benefit, with stromal vascular fraction yielding moderate improvement. Standardized protocols and long-term safety data are needed to optimize clinical use.