Feline spinal cord gliomas: Clinicopathologic and diagnostic features of seven cases

Abstract

Intraparenchymal spinal cord tumors in the cat are rarely reported and often as single case reports. In the current study, the clinical, magnetic resonance imaging (MRI), histologic, and immunohistochemical features of 7 cases of intraparenchymal spinal cord tumors in the cat are described. All cats were domestic breed, ranged from 4 to 12 years of age (median 8 years), and included spayed females (5/7) and neutered males (2/7). The duration of clinical signs ranged from 2 weeks to 3 months. MRI revealed lesions that were hyperintense on T2-weighted images with variable contrast enhancement. All 7 tumors had histologic features consistent with glial origin: 3 were astrocytic (gemistocytic or fibrous), and 2 were oligoastrocytic. Single cases of oligodendroglioma and gliomatosis cerebri were also present in the study. Glial fibrillary acidic protein immunoreactivity was robust in the tumors that were predominately astrocytic, and the gliomatosis cerebri case had extensive BLA.36 and Iba1 immunoreactivity. Ki-67 immunoreactivity was variable and most abundant in the case of malignant oligoastrocytoma. The majority of peritumoral lymphocytes were CD3 positive. The current study expands upon the known reports of spinal cord neoplasia in the cat, confirms a caudal cervical segment predilection, and includes a report of gliomatosis cerebri in the spinal cord of a cat.

Canine Gliomatosis Cerebri: Morphologic and Immunohistochemical Characterization Is Supportive of Glial Histogenesis

“…18,28 In domestic animals, GC is exceedingly rare and almost exclusively described in dogs, 2,[6][7][8][9]13,22,26,27,29,33 with single case reports in 3 cats and a goat. 4,10,31,34 GC affects mainly middle-aged dogs with no sex or breed predisposition. A familial inheritance pattern has been suggested in a group of cases affecting families of bearded collie dogs.…”

Diagnosis and clinical outcome following surgical resection of an intracranial grade III anaplastic gemistocytic astrocytoma in a cat

“… 3 There are few reports of gemistocytic astrocytomas (six intracranial cases and six spinal cord cases) reported in the veterinary literature ( Table 1 ). 4 – 6 , 18 – 21 There are fewer reports of anaplastic astrocytomas ( Table 1 ). Stigen and Eggertsdottir reported one untreated case in 2001.…”

“… 27 , 28 While an 82% accuracy of diagnosis of meningiomas has been reported on MRI, the distinction between intra- and extra-axial tumors can be challenging on imaging alone. 19 , 27 This case serves as a reminder to include neoplasms such as astrocytomas on the differential diagnosis list as well. Additionally, different regions within a tumor can have different distributions of cell types, and can lead to discordances between biopsy and post-mortem histopathology.…”

Gliomatosis Cerebri in the Brain of a Cat

“…GC has been reported in the feline spinal cord, with a similar hyperintense T2-weighted MRI signal as described in the brains of people and dogs. Feline brain and spinal cord GC has been characterized by neoplastic infiltrates that are GFAP-negative [ 14 , 20 , 21 ]. In feline spinal cord GC, the neoplastic cells are also reported to be negative for Ki-67, Pax5, and CD45, with strong cytoplasmic immunoreactivity for BLA.36 [ 21 ].…”

“…Feline brain and spinal cord GC has been characterized by neoplastic infiltrates that are GFAP-negative [ 14 , 20 , 21 ]. In feline spinal cord GC, the neoplastic cells are also reported to be negative for Ki-67, Pax5, and CD45, with strong cytoplasmic immunoreactivity for BLA.36 [ 21 ]. Additional microscopic features of GC in people and dogs include perineuronal and perivascular satellitosis, subpial and subependymal neoplastic aggregates, and migration of neoplastic cells within white matter tracts (intrafascicular spread) [ 9 ].…”