Comparative study of angiogenesis in thyroid glands with Graves disease and Hashimoto's thyroiditis

Angiogenesis entails the sprouting of new vessels from pre-existing vasculature. In adults, angiogenesis occurs in the thyroid gland during disease processes such as hyperplastic goiter, Graves disease, thyroiditis, and cancer. In the present study multiple morphologic characteristics of microvessels were measured in and compared between 18 cases of Graves disease, 29 cases of Hashimoto's thyroiditis, and 15 control cases. All histologic sections were immunostained for CD31. Quantification of microvessel density (MVD), major axis length, minor axis length, area, perimeter and shape factor was performed by image analysis. MVD was increased significantly in both forms of autoimmune thyroid disease. Significantly higher values were found in Graves disease in comparison to Hashimoto's thyroiditis. In contrast, major axis length, minor axis length, and area had significantly higher values in Hashimoto's thyroiditis than in Graves disease. The statistical analysis revealed MVD as the unique significant morphometric factor discriminating the two autoimmune entities.