A case of ependymoma in a dog; computed tomography, histopathological and immunohistochemical findings

Abstract

An 11-year-old intact female Maltese was referred because of 1 week history of cluster seizure episodes. Based on brain CT scan, brain tumor was strongly suspected. The patient was euthanized according to client's request and we performed necropsy after euthanasia. The gross findings of the postmortem coronal sections of the brain showed that the mass was relatively well-demarcated, reddish in colored, and was present inside the left lateral ventricle and compressed adjacent tissues. The tumor mass had 2 distinct histopathological features: Perivascular pseudorosette-like structures and a whirl-like arrangement of fibrillary cells. The immunohistochemical profile showed strong GFAP positivity and moderate S-100 expression, sparsely dotted staining with Ki-67. Based on the histopathological and immunohistochemical findings, the present case diagnosed to ependymoma.