Intramedullary Hemangioblastoma in a Dog

Abstract

Abstract.A 6-year-old male Pointer dog was presented with a 4-week history of progressive hind-limb stiffness. Magnetic resonance imaging demonstrated a focal intramedullary lesion at T 1 level with a pattern of ring contrast enhancement. At necropsy, a circumscribed intramedullary reddish-gray tumor was observed. Microscopically, the tumor was composed of thin-walled capillaries lined by endothelial cells and separated by pleomorphic cells (stromal cells) with a moderate degree of anisokaryosis. Immunohistochemically, the endothelial cells were positive for factor VIII-related antigen and the stromal cells were positive for neuron-specific enolase and vimentin. GFAP-positive astrocytes were occasionally observed within the tumor. Both endothelial and stromal cells were negative for synaptophysin, S-100 protein, pankeratin, smooth muscle actin, CD34, CD68, ␣1-antichymotrypsin, and lysozyme. The tumor showed considerable morphologic and immunohistochemical similarities with human hemangioblastoma, and hence the inclusion of this tumor type within the primary neoplasms of the canine central nervous system is suggested.

Imaging Diagnosis—magnetic Resonance Imaging Features of a Cerebral Hemangioblastoma in a Dog

“…2 The histopathological findings in our case are similar to human reports and the previously reported intramedullary case in a dog. [2][3][4] In humans, hemangioblastomas are intraparenchymal neoplasms, most commonly located in the cerebellum. 1,5 Intramedullary lesions are uncommon and supratentorial lesions are rare.…”

“…Neuron-specific enolase staining of the interstitial cells occurs in human hemangioblastoma 3 and in the canine variant. 2 Our MRI interpretation erroneously classified the lesion as more likely extraparenchymal, though an intraparenchymal location was also deemed possible. The MRI findings shared similarities with those seen in meningiomas, including a suspected extraparenchymal location, broadbased appearance, and marked homogeneous contrast enhancement.…”

“…The MRI characteristics of intracranial and intramedullary hemangiomas have been published recently, 17, 20 but the contrast enhancement of the reported intracranial hemangiomas were patchy and heterogeneous, while histologically they represent distinct entities compared to the case reported here and the previously reported intramedullary case. 2 The reason for deterioration in this case following surgery is unclear, but could have been the result of hemorrhage, infection, tension pneumocephalus, or a combination of these recognized complications. 21 Hemangioblastomas behave most commonly as benign neoplasms, 1, 5 with a control rate for tumor growth approaching 80% in humans following gamma knife surgery.…”

Intramedullary Spinal Cord Neoplasia in 53 Dogs (1990–2010): Distribution, Clinicopathologic Characteristics, and Clinical Behavior

“…Only 5% of secondary tumors in humans are diagnosed antemortem, and affected patients present more acutely and progress more rapidly than patients with primary tumors . Clinical progression in previous veterinary reports ranged from 1 to 504 days (mean, 55.7 days; median, 21 days) . Our data also indicated a variable clinical course.…”

“…Fifty‐six intramedullary spinal cord tumors have been reported in the veterinary literature . Primary tumors were documented in 41 cases and secondary tumors in 15 cases . The mean age, recorded for 49/55 cases, was 4.7 years.…”