Ectopic insulinoma in a bitch (Canis familiaris)

Abstract

Ectopic insulinoma is a rare neoplasm derived from ectopic tissue of pancreatic beta cell islets. The definitive diagnosis is given by histopathological and immunohistochemistry analysis. This study reports the case of a 9‐year‐old dog with a history of persistent hypoglycaemia, hyperinsulinism and seizures, which after undergoing imaging examination and exploratory celiotomy was diagnosed with stage III ectopic insulinoma. During surgery, no alterations were observed in the pancreas. Nevertheless, there was a nodule in topography of the left hepatic lymph node, next to the portal vein, without adhesions or communication with the pancreas. The animal had hepatic lesions in the liver. Histopathological examination revealed the presence of ectopic insulinoma and hepatic metastases. The anti‐insulin antibody was positive on immunohistochemistry. The dog underwent palliative treatment with corticosteroid and toceranib phosphate, showing a positive response to treatment, maintaining quality of life and few adverse effects. Its survival time was 200 days since diagnosis.