Two cases of epithelioid angiosarcoma involving the thyroid and a brief review of non-Alpine epithelioid angiosarcoma of the thyroid.

Epithelioid angiosarcoma involving the thyroid is a rare entity, more often described in the Alpine region. Two cases of epithelioid angiosarcoma that affected the thyroid in patients from a non-Alpine location were diagnosed during a 10-year period in our department. The first case occurred in an 89-year-old Chinese man with a history of longstanding goiter, whereas the second case involved a 74-year-old Chinese man with a history of angiosarcoma of the scalp. On histologic examination, both thyroid tumors were composed of plump epithelioid cells with vesicular chromatin and prominent nucleoli, forming vascular structures and solid sheets. Positive staining for CD31 and factor VIII-related antigen confirmed endothelial differentiation in both cases. Both patients died within 5 months following the diagnosis of thyroid disease. The relationship of the scalp angiosarcoma and thyroid disease of the second patient is unclear. A brief review of non-Alpine primary thyroid epithelioid angiosarcoma is presented.