Abstract
BACKGROUND: Pediatric hepatic angiosarcoma is a rare condition in children with poor prognosis. Microscopically this neoplasm has a particular 'Kaposi-form' arrangement. Hemangiosarcoma in non-human primates is a rare finding. METHODS: Gross and microscopic examination of a 3-year-old rhesus were performed. Immunohistochemistry was used to characterize the hepatic hemangiosarcoma. RESULTS: The gross necropsy revealed hemoabdomen and a 4 x 3 x 3 cm mass in the liver with multiple smaller masses throughout the hepatic parenchyma. Histopathology confirmed a poorly differentiated hemangiosarcoma. Other organs submitted were free of metastases. CONCLUSIONS: Hemangiosarcoma in non-human primates has been rarely reported. Diagnosis was confirmed by expression of endothelial-specific markers CD31 and vWF by immunohistochemistry. Due to the young age of this monkey and the particular solid pattern throughout the mass this neoplasm resembles pediatric hepatic angiosarcoma in humans.