Canine spinal cord glioma.

Spinal cord glioma is uncommonly reported in dogs. We describe the clinicopathologic and diagnostic features of 7 cases of canine spinal cord glioma and briefly review the veterinary literature on this topic. The median age at presentation was 7.2 y. Six females and 1 male were affected and 4 dogs were brachycephalic. The clinical course lasted from 3 d to 12 wk, and clinical signs were progressive and associated with multiple suspected neuroanatomic locations in the spinal cord. Magnetic resonance imaging of 6 cases revealed T2-weighted hyperintense lesions with variable contrast enhancement in the spinal cord. All dogs had a presumptive clinical diagnosis of intraparenchymal neoplasia or myelitis based on history, advanced imaging, and cerebrospinal fluid analysis. Euthanasia was elected in all cases because of poor outcome despite anti-inflammatory or immunosuppressive treatment or because of poor prognosis at the time of diagnosis. Tumor location during autopsy ranged from C1 to L6, with no clear predilection for a specific spinal cord segment. The diagnosis was based on histopathology and the immunohistochemistry expression of glial fibrillary acidic protein, oligodendrocyte lineage transcription factor 2, 2',3'-cyclic-nucleotide 3'-phosphodiesterase, neuron-specific enolase, synaptophysin, and Ki-67. Diagnoses consisted of 4 cases of oligodendroglioma, 2 cases of gliomatosis cerebri, and 1 astrocytoma. This case series further defines the clinicopathologic features of canine spinal glioma and highlights the need for comprehensive immunohistochemistry in addition to routine histopathology to confirm the diagnosis of these tumors.