in 13 out of 20 thyroid tumors , classified by light microscopy as malignant hemangioendothelioma , factor viii-related antigen , a marker for endothelial cells , was demonstrated in neoplastic cells with the help of immunohistochemical technics applied to conventional paraffin sections .
C0018923
malignant hemangioendothelioma
C0225336
endothelial cells