An Algorithm for Treatment of Radiation-Induced Soft Tissue Damage with Products Based on Autologous Adipose Tissue

Purpose

Even though efficiency of fat grafting and adipose-derived stromal vascular fraction injection for radiation-induced soft tissue injury treatment was supported by clinical practice, there are some questions concerning using of these methods still remains unsolved. The aim of our study was to develop an algorithm for management of radiation-induced soft tissue damage with products based on autologous adipose tissue.

Methods and materials

Since 2010 123 patients with late soft tissue radiation damage were treated by injection of products based on autologous adipose tissue. In group 1 containing 44 patients with chronic radiation wounds (LENT-SOMA grade 4) the goal was to completely heal a sore. In group 2 including 21 patients with radiation fibrosis (LENT-SOMA grade 2,3) the treatment was directed to prevention of radiation necrosis. For the rest of 58 patients (group 3) primary goal was to correct contour deformities after previous surgery combined with radiotherapy. Radiolesions were localized in breast, head and neck, trunk, extremities and rectovaginal septum in 59, 24, 21, 11 and 18 patients respectively. Liposuction was performed with barbed cannula 2,5 mm in diameter with fourteen 1,5 mm holes.  Three different products based on autologous lipoaspirate were used depending on clinical needs: centrifuged at 1250 g force for 3 minutes microfat, nanofat obtained by mechanical emulsification and filtration of decanted microfat, and stromal-vascular fraction isolated by collagenase type 2 digestion of fat. Overall number of surgical procedures was 523. Photography, elastosonography, magnetic resonance imaging and histology were used for results assessment.

Results

Favorable outcome have been achieved in all cases. In the first group complete healing was observed in 98% (43 out of 44 patients). From one to three procedures was performed to get final result. Average healing time depended on size and depth of the wound and ranged from 8 to 14 weeks. Only in one case only VRAM flap was performed due to progressive osteoradionecrosis of the ribs. In the second group decreasing of LENT-SOMA grade was observed in all patients. Density of fibrotic tissues measured with elastosonography decreased from 220-650 kPa to 30-50 kPa. In the third group from 2 to 4 procedures were necessary to restore soft tissue flexibility. As far as density level becomes less than 60 kPa, additional 2-6 fat grafting sessions were performed to attain necessary volume and shape.

Conclusions

Late adverse effects of radiation therapy can be successfully prevented and treated with injection of products based on autologous lipoaspirate. This minimally invasive approach demonstrates extremely high efficiency rate and allows to avoid major surgery in most of the cases. As far as treatment of severe chronic radiation wounds may be associated with well-known issues it is seems to be reasonable to apply described techniques for patients with initial signs of late radiation-induced soft tissues damage in order to prevent necrotic complications. Proposed treatment algorithm, that takes into account LENT-SOMA stage, anatomical site and wound bed features, can be helpful for developing an effective management protocol for patients with soft tissue radiolesions.