RESUMEN
Neoplasms of the exocrine pancreas are uncommon in domestic animals and rarely occur in wildlife. This article describes the clinical and pathological findings of one case of metastatic exocrine pancreatic adenocarcinoma in an 18-year-old giant otter (Pteronura brasiliensis) in captivity with a history of inappetence and apathy. Abdominal ultrasonography was inconclusive, and tomography revealed a neoplasm affecting the urinary bladder and hydroureter. During the anaesthesia recovery, the animal presented a cardiorespiratory arrest and died. Grossly, there were neoplastic nodules in the pancreas, urinary bladder, spleen, adrenal glands, and mediastinal lymph node. Microscopically, all nodules were composed of a malignant hypercellular proliferation of epithelial cells with acinar or solid disposition, supported by a sparse fibrovascular stroma. Neoplastic cells were immunolabeled with antibodies to Pan-CK, CK7, CK20, PPP and chromogranin A. Approximately 25% of the cells were positive for the presence of Ki-67 too. Pathological and immunohistochemical findings confirmed the diagnosis of metastatic exocrine pancreatic adenocarcinoma.