Hemorrhage and Sudden Death in a Cat with Pancreatic Hemangiosarcoma

SIMPLE SUMMARY: Feline pancreatic neoplasia is a rare clinical and post-mortem diagnosis. This report aims to present the pathological findings of a case of pancreatic hemangiosarcoma in a cat with a history of sudden death. A neoplastic mass, covered by numerous small blood clots, was identified within the body of the pancreas, along with multiple metastases within the omentum and liver. The sudden death was most likely caused by the spontaneous rupture of the pancreatic neoplasm, which produced severe hemoperitoneum and anemia. Cytological and histological findings were completed by immunohistochemical evaluation, supporting the diagnosis of hemangiosarcoma. ABSTRACT: A 15-year-old female, indoor, spayed, domestic shorthair cat was presented for post-mortem evaluation with a history of sudden death. A red-brown 3 cm x 4 cm neoplastic mass was identified within the body of the pancreas, along with multiple similar nodular structures within the omentum and liver. Associated lesions included hemoperitoneum, yellow discoloration of the peritoneal wall, and severe anemia. Spindle-shaped neoplastic cells exhibiting malignancy features, which occasionally contained within the cytoplasm haematoidin crystals and/or red blood cells, were observed during cytological examination. Histologically, the neoplastic cells were organized in short streams forming vascular spaces filled with erythrocytes. Immunohistochemically, the neoplastic cells were immunolabeled for vimentin and CD31, supporting the diagnosis of hemangiosarcoma. This report offers a complete post-mortem and histological evaluation of a rare tumor in cats with an unusual location and a comparative assessment of 3 anti-CD31 antibodies.