Expression of Vascular Endothelial Growth Factor and Its Receptors in Thyroid Nodular Hyperplasia and Papillary Thyroid Carcinoma: A Tertiary Health Care Centre Based Study

Introduction: Vascular endothelial growth factor (VEGF) is an angiogenic factor that plays an important role inthyroid cancer. VEGF is known to have high affinity to VEGF receptors such as VEGFR-1 (Flt-1) and VEGFR-2 (KDR).Papillary thyroid carcinoma (PTC) is the most common thyroid cancer and studies showed the increasing incidence ofPTC arising in nodular hyperplasia. Targeted therapy on these growth factors and receptors are used in managementof both differentiated and undifferentiated thyroid carcinoma. This study aims to determine the expression of VEGFand VEGF receptors (VEGFR) in thyroid nodular hyperplasia and PTC. Methods: A cross-sectional study based onparaffinized archival tissue blocks of 113 nodular hyperplasias and 67 PTC from the thyroidectomy specimens inthe year of 2003 to 2014. The tissue sections were then stained by immunohistochemistry for VEGF, VEGFR-1 andVEGFR-2. The lymph node involvement and extrathyroid extension also were determined. Results: The mean age ofPTC patients was 44.7±15.8 years and nodular hyperplasia were 42.2±13.6 years. There was a statistical differenceof VEGFR-1 (p=0.028) and VEGFR-2 (p=0.003) expression between nodular hyperplasia and PTC. However, nosignificant difference of VEGF expression (p=0.576) between both diseases. Co-expression of VEGF and VEGFR-1was significant in both nodular hyperplasia (p=0.016) and PTC (p=0.03), meanwhile no relevant relationship for VEGFand VEGFR-2 expression (p>0.05). No significant association (p>0.05) between lymph node status and extrathyroidextension with age groups, gender, VEGF and VEGFR expression. Conclusions: VEGF, VEGFR-1 and VEGFR-2showed overexpression in both nodular hyperplasia and PTC. The expression of VEGFR-1 and VEGFR-2 are moresignificant in PTC with relevant co-expression of VEGF and VEGFR-1. Therefore, the inhibition of VEGFR offers apromising prospect for tumour management in thyroid carcinoma.