BACKGROUND: The main problem with fat grafting is the postoperative graft resorption which often leads to repeated procedures to achieve the desired volume. Cell therapy in the form of adding stromal vascular fraction or culture-expanded, adipose-derived stromal cells to the fat graft are some of the most promising strategies to improve graft retention.1 To assess the efficacy of using high-dose, culture-expanded, adipose-derived stromal cells to enhance fat graft volume retention in the human breast, we have conducted a randomized, double-blind, placebo-controlled clinical trial.
METHODS: This clinical trial was performed in healthy women with small, symmetrical breasts who underwent a bilateral breast augmentation by fat grafting. In each patient, one breast was treated with normal fat grafting and the other with fat grafting enriched with expanded adipose-derived stromal cells (10 × 106 cells/ml fat). The patients underwent 2 surgeries: (1) a small liposuction to obtain the adipose tissue for isolation and ex vivo expansion of the cells for 17 days and (2) a larger liposuction after 17 days to conduct a bilateral breast augmentation with fat grafting with unilateral addition of the expanded cells. Magnetic resonance imaging scans of the breast were performed the day before breast augmentation and 4 months and 1 year after surgery. The primary outcome was fat graft volume retention after 4 months and 1 year based on magnetic resonance imaging. The study is registered at www.clinicaltrialsregister.eu and was approved by the National Ethics Committee in Denmark (number: 2014-000510-59).
RESULTS: Ten women were enrolled in the study. The mean fat graft volume per breast augmentation was 310 ml fat (range, 300–350 ml). The cell enrichment of the fat grafts did not improve the volume retention after 4 months or 1 year. After 4 months, the retention of the cell-enriched grafts was 54.3% (95% confidence interval [CI], 39.4–69.2) versus 56.2% (95% CI, 42.7–69.6) in the control group (P = 0.552). After 12 months, the retention in the cell-enriched grafts was 54.0% (95% CI, 30.4–77.6) versus 55.9% (95% CI, 28.9–82.9) in the control group (P = 0.566). The difference in mean retention after 1 year was only −1.9 % (95% CI, −9.11% to 5.31%). No serious adverse events occurred in any of the patients.
CONCLUSION: Our study showed that enriching fat grafts with high-dose expanded adipose-derived stromal cells did not lead to any improvement in fat graft survival in the breast.
1. Kolle SF, Fischer-Nielsen A, Mathiasen AB, et al. Enrichment of autologous fat grafts with ex-vivo expanded adipose tissue-derived stem cells for graft survival: a randomised placebo-controlled trial. Lancet. 2013;382:1113–1120.