Fig. 4. Histopathological findings of recurrent angiosarcoma dissemination. (A) Hematoxylin–eosin staining shows solid vascular proliferations of atypical endothelial cells without residual mucinous carcinoma or teratomatous components (×400). (B) Immunohistochemistry for CD31 highlights diffuse membranous staining of the neoplastic endothelial cells (×400). (C) ERG immunostaining shows strong nuclear positivity in the tumor cells (×400). (D) Ki-67 immunostaining reveals a very high proliferative index of approximately 90% (×400).
