Ultrastructural and immunohistochemical observation on angiosarcoma

Objective: To summarize the morp hology, immunohistochemistry and ultrastructure of angiosarcoma and to discuss the significance in diagnosis and differentiated diagnosis. Methods: All Of 10 cases of angiosarcoma samples fixed with 10% formeldehyde were stained by ro utine HE and immunohistochemistry and observed by light microscope. Of them,5 samples were observed by electron microscope.Results: The tumors were pleomorphous and many irregular blood vessels varied in size were inosculat ed each other and formed vascular web which was lined by atypical tumorous endothelia cells. The cells in poor differentiated tumor sh owed diffuse, massive and nest-like arrangement and the vascular cavity was unclear and make it difficult to diagno se. The immunohistochemical results showed F8RA and CD44 positive in all cases. The ultrastructural observation of angios arcoma showed that the tumor cells and pericytes were circumvented by more incomplete basal lamina and Weibel-Palade bo dies were seen in the cytoplasm of the tumor cells.Conclusion:Ultrastructural observation a nd immunohistochemistry has determined significance in diagnosis of angiosarcoma.