The effect of adipose stromal vascular fraction on transverse rectus abdominis musculocutaneous flap: an experimental study

Background: Transverse rectus abdominis musculocutaneous (TRAM) flap is one of the options in reconstruction after breast cancer surgery for breast reconstruction. Tissue necrosis often occurs in the third and fourth perfusion zones of the flap. A study was planned to find out the effects of adipose stromal vascular fraction (SVF) cells on viability of TRAM flap and the experimental model was designed to be applicable in clinical practice. Methods: Right inferior epigastric artery pedicled, 5x2.5cm sized TRAM flap was used as a flap model in 30 rats in three groups (group 1: sham; group 2: phosphate-buffered saline (PBS); group 3: SVF cell injected). The viability of the flaps were assessed on the postoperative 7th day with photographs and software for the calculations. Results: The mean viable flap percentage to total flap area was recorded as 51.8%+/- 11.19, 49.5%+/- 10.30, 82.3%+/- 9.56, in group 1, group 2, and group 3, respectively (p<0.05). The mean capillary density was noted as 5.15 +/- 0.56, 4.37 +/- 0.58, and 12.40 +/- 1.17 in groups 1, 2, and 3, respectively (p<0.05). The fibrosis gradient indicated no difference between the groups (p>0.05). The in-vivo differentiation of SVF cells to endothelial cells was noted. The blood VEGF levels showed a marked increase in the experimental group (p<0.05). Conclusion: The adipose SVF cells were found out to improve the TRAM flap viability and decrease necrosis, especially in zone 3 and 4.