The effect of bevacizumab and 5-Fluorouracil combination on epidural fibrosis in a rat laminectomy model.

OBJECTIVE: An animal model of laminectomy in rats was used to study scar tis - sue formation around the spinal cord. Beva - cizumab (BV) (a recombinant, humanized, mono - clonal antibody targeting vascular endothelial growth factor), 5-Fluorouracil (5-FU) and BV+5- FU was tested in this system for its ability to de - creasefibroustissueformation. MATERIALS AND METHODS: Twenty-eight Sprague Dawley rats were used in this sudy. Rats were divided into four groups; a control group, a BVgroup,a5-FUgroupandaBV+5-FUgroup.L1- 2 laminectomies were performed on the rats.The medicated groups were treated with topical drug administration. After 6 weeks, the rats were sacri- fied and histologic sections prepared from the spines were examined and graded by a patholo - gist. Epidural fibrosis and fibroblast density were evaluatedunderlightmicroscope. RESULTS: BV (Avastin: Genentech, San Fran - cisco, CA, USA) significantly reduced the densi- ty of the scar tissue undermining the laminas ( p < 0.005). Monotherapy with 5-FU did not change the scar formation in the back ( p = 0.317). Com - bination of 5-FU and BV was more effective on reducing the epidural fibrosis after laminectomy onrats( p<0.001). CONCLUSIONS: Bevacizumab reduced the spinal epidural fibrosis significantly that devel- oped in rats after laminectomy and 5-Fluo - rouracil combination had a synergic effect. Fur - ther investigations under the light of these find - ings may help to reduce epidural fibrosis forma - tionafterlaminectomy.