Abstract: Objective：To investigate the correlation between the expression of estrogen receptor alpha(ERα) and vascular epithelial growth factor (VEGF) in different histopathological variants in patients of papillar thyroid carcinoma(PTC). Methods： Compare with and study the expression of ERα and VEGF which were examined by SP immunohistochemistry in 59 cases of PTC , 56 cases of thyroid adenoma, 30 cases of normal thyroid tissues. Results：The positive expression rate of ERα in cases with PTC, thyroid adenoma and normal thyroid tissue were 83.05%,58.93% and 30% respectively. There was significant difference between　　 PTC and adenoma or normal thyroid tissue(p<0.01).The positive expression rate of VEGF in cases with PTC, thyroid adenoma and normal thyroid tissue were 64.41%,39.29% and negative respectively. There was significant difference between　　 PTC and adenoma or normal thyroid tissue(p<0.01). The ERα and VEGF expression of PTC were related with the histological variant as well as lymph node metastasis（P＜0.05）.The ERα expression was positively correlated with the VEGF expression in PTC(r = 0.514，P = 0.033). Conclusion：The ERα may stimulate proliferation and promote differentiation of the thyroid epithelial cells. The increase of ERα expression may play a role in promote the angiogenesis and development of PTC.

Key words: thyroid tumor, ERα, VEGF, immunohistochemistry