Canine Hemangioblastoma: Case Series and Literature Review.

Human hemangioblastoma is a benign, slow-growing, highly vascular neoplasm. The tumor most commonly arises in the cerebral hemispheres and cerebellum, where it is more frequently observed in patients with von Hippel-Lindau disease. In veterinary medicine, hemangioblastoma has only been described in the central nervous system of dogs and in the skin of lambs. Our study aimed to characterize the clinical and neuropathological features of five cases of canine spinal cord hemangioblastoma and one case of sciatic nerve localization, and to compare these results with those reported in the veterinary literature. Diagnoses were achieved by neurological examination, neuroimaging, surgery or post-mortem examination, histopathology, and immunohistochemistry. All tumors were composed of numerous, haphazardly arranged capillaries lined by plump endothelium and interstitial fusiform to stellate stromal cells. Immunohistochemically, the stromal cells were strongly immunolabeled with NSE and carbonic anhydrase IX and were negative for von Willebrand factor VIII and inhibin-α. Canine hemangioblastoma exhibits morphological and immunohistochemical features comparable to the human counterpart, although the latter is mostly positive for inhibin-α. Surgery may be effective in cases of intradural-extramedullary and peripheral nerve locations, as in humans. This is the first report of peripheral nerve hemangioblastoma in animals.