Effect of mitomycin, bevacizumab, and 5-Fluorouracil to inhibit urethral fibrosis in a rabbit model.

Abstract

Mitomycin C (MMC), bevacizumab, and 5-fluorouracil (5-FU) are frequently used in cancer treatment. Each of these agents also exhibits antiproliferative properties in different tissues. We compared the efficacy of MMC, bevacizumab, and 5-FU may inhibit urethral fibrosis (UF) without statistically significant differences among them. Forty male rabbits with traumatized urethras were divided into four groups: Group 1 (control), no medical treatment; group 2, MMC applied to the traumatized area; group 3, bevacizumab applied to the traumatized area; and group 4, 5-FU applied to the traumatized area. All animals were euthanized after 28 days to evaluate the presence of chronic inflammation and fibrosis. Tissue samples were subjected to hematoxylin and eosin and Masson trichrome staining to assess the presence of fibrosis, the state of the epithelium, and collagen density. The MMC and control groups showed the most significant difference in outcomes (P<0.001), followed by the bevacizumab (P=0.002) and 5-FU groups (P=0.005). No statistically significant difference was noted when all three treatment groups were compared with one another. Histopathologic examination revealed inflammatory cell infiltration in the connective tissue, irregular collagen bundles, increased fibroblasts, and a moderate degree of fibrosis in the control group. Compared with controls, all treatment groups exhibited mild fibrosis, less collagen bundle irregularity, and lower numbers of fibroblasts. MMC, bevacizumab, and 5-FU may inhibit UF. There were no statistically significant differences in the effectiveness among the three agents.