ABSTRACT
PURPOSE: Increased expression of angiogenic factors and high vascular density characterize tumors with increased invasive and metastatic capability. Anti-vascular endothelial growth factor (VEGF) therapies have shown an important potentiation of chemotherapy and radiotherapy in experimental and clinical studies. The purpose of this study was to investigate whether it could be possible to identify a subgroup of thyroid cancer patients with high angiogenic activity. METHODS: Formalin-fixed paraffin-embedded tissues from 25 papillary and 18 follicular thyroid carcinomas were assessed immunohistochemically for angiogenic activity, i.e. vascular density (VD) and expression of VEGF and basic fibroblast growth factor (bFGF). RESULTS: VD was significantly higher in follicular tumors (p=0.05). Tumors > 4 cm had a significantly higher VD (p=0.001). High VEGF expression was significantly related to high VD (p=0.05). There was no association of bFGF with histological characteristics. CONCLUSIONS: Increased angiogenic activity is a common feature of thyroid carcinomas, particularly in follicular tumors and larger carcinomas. These results support the testing of anti-VEGF therapies in combination with radiotherapy and chemotherapy in advanced thyroid tumors.
