Early effects of triamcinolone on vascular endothelial growth factor and endostatin in human choroidal neovascularization

Objective: To evaluate the early effects of triamcinolone acetonide as monotherapy or as an adjuvant to ocular verteporfin photodynamic therapy (PDT) on angiogenesis in human choroidal neovascularization (CNV) secondary to age-related macular degeneration. Methods: Retrospective review of an interventional series of 55 patients who underwent CNV extraction. Eleven patients were treated with intravitreal triamcinolone acetonide (4 mg) monotherapy (triamcinolone-treated CNV group [n=5]) or with PDT-triamcinolone combination therapy (PDT-triamcinolone-treated CNV group [n=6]) 3 to 9 days before surgery. Forty patients who underwent CNV extraction without previous therapy (control CNV group) and 4 patients who underwent CNV extraction 3 days after PDT (PDT CNV group) served as control subjects. The CNV samples were stained for CD34, endostatin, cytokeratin 18, and vascular endothelial growth factor (VEGF). Results: Vascular endothelial growth factor expression was stronger in the PDT CNV samples (P<.001), triamcinolone CNV samples (P=.01), and PDT-triamcinolone CNV samples (P=.007) compared with the control CNV samples. There were no statistically significant differences in VEGF expression among the PDT CNV samples, triamcinolone CNV samples, and PDT-triamcinolone CNV samples. Endostatin expression was weaker in the PDT CNV samples than in the control CNV samples (P=.008). Endostatin expression was stronger in the triamcinolone CNV samples and the PDT-triamcinolone CNV samples compared with the control CNV samples (P=.001 and P<.001, respectively) and the PDT CNV samples (P<.001 for both). Conclusion: To some extent, triamcinolone monotherapy seems to exert its angiogenesis inhibitory effects on CNV by enhancing endostatin expression rather than by suppressing VEGF expression.