Abstract
A 5-year-old castrated Japanese domestic cat was presented with persistent vomiting. Ultrasound examinations revealed many masses only in the liver, and the fine needle aspiration was performed. Cytologically, polygonal or oval shaped tumor cells forming rosette and cord-like patterns were demonstrated, and then, the hepatic lesions were diagnosed as neuroendocrine carcinoma tentatively. The cat died one month after admission and was necropsied. Histopathologically, the tumor cells of the hepatic mass were arranged in typical rosette and cord-like structures. They were considerably uniform in size with hyperchromatic round nuclei and eosinophilic cytoplasm. Most of tumor cells were immunopositive for chromogranin A, and some were positive for gastrin. The findings indicate the possibility that the present case was a gastrin-producing neuroendocrine carcinoma.