Hemangiopericytoma in a young dog: Evaluation of histopathological and immunohistochemical features

In the present study, we describe a subcutaneous mass between the left flank and hip in a 2-year-old male Great Dane dog. Histopathologically, cells appeared to be spindle shaped around a central capillary together with a fingerprint pattern. Immunohistochemical analysis presented that the neoplastic cells expressed vimentin, but did not stain for S-100 protein. On the basis of histopathology and immunohistochemical findings, the present tumor was diagnosed as canine hemangiopericytoma. Hemangiopericytoma could be considered in differential diagnosis list of any mass in the skin (even in young dogs) and must be identified histopathologically.