Increased Expression of Vascular Endothelial Growth Factor and Its Receptors, VEGFR-1 and VEGFR-2, in Medullary Thyroid Carcinoma

Background: Vascular endothelial growth factor (VEGF-A) expression is upregulated in the majority of human tumors, where it stimulates proliferation, migration, and survival of endothelial cells. Studies have suggested that VEGF inhibitors can be used as an alternative therapy in medullary thyroid carcinoma (MTC), but data about expression of VEGF-A and its receptor in this tumor are scarce. The aims of this study were to evaluate VEGF-A, VEGF receptor (VEGFR)-1, VEGFR-2, and microvessel density (MVD) expression in MTC samples and correlate it with clinical parameters. Methods: Paraffin-embedded samples from 38 MTC patients were evaluated for VEGF-A, VEGFR-1, VEGFR-2, and MVD expression by immunohistochemistry. Clinical data were retrospectively reviewed in medical records. Results: Thirty-eight patients aged 31.8 ± 17.1 years were enrolled. Twenty-seven patients had hereditary disease (71.1%). Twenty-five of them were found to have multiple endocrine neoplasia (MEN) 2A and two were found to have MEN 2B. ...