MESOTHELIOMA: A CASE REPORT.

Mesothelioma is a neoplasm that starts in the mesoderm and can have a pleural, pericardial or peritoneal origin.Occasionally, it is found in the tunica vaginalis (3,5,8).There is a higher incidence in dogs, with genetic predilection in German Shepherds.Likewise, male geronts are more predisposed to present it and it is related to asbestos exposure(3,8).Effusions, whether pleural, peritoneal or pericardial, are some of the disorders related to mesothelioma(3).For diagnosis, it is recommended to perform immunohistochemical tests by means of Calretinin antibody, since it identifies neoplastic mesothelial cells and differentiates these cells with those of adenocarcinoma(9,11). Alcian blue stain is also used, because mesotheliomas present an increase in acid mucosubstances not sulfated, so it stains them(7).We describe the case of a five-year-old male German Shepherd canine that clinically presented abdominal distension, with clinical signs of anorexia and weight loss.Clinical biochemistry showed altered liver enzymes and hypoproteinemia.At abdominocentesis, an amber colored fluid was obtained, with a density of 1.031.The patient was euthanized and at necropsy, samples were taken from the diaphragm, peritoneum and small intestine for histopathology.A diagnosis of mixed mesothelioma was made based on histopathology, Calretininin immunohistochemistry and Alcian Blue Stain.Which has a rare incidence, so it is considered relevant to document this case.