Is there an ideal recipient site preconditioning to improve autologous fat graft retention in breast surgery? A prospective multi-center randomized controlled trial.

Abstract

Autologous fat grafting (AFG) is a popular method for soft tissue augmentation and reconstruction due to its regenerative potential and minimally invasive nature. However, variability in fat graft retention remains a major limitation. While research has focused on optimizing fat harvesting and processing techniques, the role of recipient site preparation has been understudied. This trial evaluated whether preconditioning the recipient site-via pre-expansion, pre-heating, or both-could enhance fat graft retention around the breast six months post-operatively. In a prospective, multi-center, randomized controlled trial (RCT) with a 2×2 factorial design, 60 female patients were assigned to one of four groups: (1) pre-expansion using the Kiwi® VAC-6000M with PalmPump™, (2) pre-heating using the HILOTHERM® Calido system, (3) a combination of both interventions, or (4) a control group without preconditioning. The primary outcome was the percentage of fat graft volume retained at the breast at six months relative to baseline at screening. Secondary outcomes included scar quality (Patient and Observer Scar Assessment Scale), pain levels (Numeric Rating Scale), and complications (Clavien-Dindo classification). No statistically significant difference in fat retention was observed between the treatment and control groups at six months. All groups (including control) showed improvement in scar quality and reduced pain, though the improvement was not different between the arms. All preconditioning methods were well tolerated, and no serious adverse events were reported. This is the first RCT to evaluate recipient site preconditioning in AFG around the breast. The interventions did not yield statistically significant improvements in fat graft survival, pain, or scarring. Given their safety, feasibility, and the biological rationale supporting their use, these techniques warrant further investigation in larger, adequately powered trials. Future studies should focus on identifying patient subgroups most likely to benefit and exploring long-term outcomes beyond six months. Level 1 (randomized clinical trial).