Figure 4
From: Primary cranial mediastinal hemangiosarcoma in a young dog
Cranial mediastinal hemangiosarcoma. (A) The sample consists of residual fat with some fibrous stroma and there are multifocal, extensive areas of hemorrhage. Surrounding areas of hemorrhage are composed of nests of neoplastic endothelial cells, 50X H&E stain objective. (B) The cells are tightly packed with minimal amphophilic cytoplasm and hyperchromatic plump oblong nuclei with coarsely stippled chromatin and a single nucleolus, 200X H&E stain objective. (C) CD31 immunohistochemistry shows immunoreactivity of cells lining vascular channels. Atypical spindle cells are positive for CD31, 20X CD31 stain objective. (D) Factor VIII immunohistochemistry shows immunoreactivity of cells lining vascular channels. Atypical spindle cells are positive for factor VIII, 20X factor VIII stain objective.