Publicação online; 14 ref.; 4 illus.; Summaries (En, Pt)

ABSTRACT - This paper reports a case of a rare variant of the cervical spinal cord astrocytoma diagnosed in a dog with progressive neurological signs, initially asymmetrical, not ambulatory tetraparesis, segmental reflexes and normal muscle tone in all four limbs and absence of pain upon palpation of the cervical spine. Myelography revealed attenuation of the ventral and dorsal contrast line in the third region of the fifth cervical vertebra. At necropsy intramedullary cylindrical mass that stretched from the third to the sixth cervical vertebra, which replaced all the gray matter of the spinal cord was observed. In the histological study, there was the replacement of the substance by neoplastic cells mantle arranged loosely. The cells were large and slightly rounded. The eosinophilic cytoplasm was well defined, sometimes forming processes interconnecting cells. The nucleus was eccentric, round, oval or kidney-shaped, and the nucleolus was evident. Thus, the microscopic changes observed in the cervical spinal cord were consistent with gemistocytic astrocytoma.


Keywords: canine, neoplasm, glioma, spinal cord

RESUMO - Relata-se um caso de uma variante rara de astrocitoma na medula cervical, diagnosticado em cadela com sinais neurológicos progressivos, inicialmente assimétricos, de tetraparesia não ambulatória, com reflexos segmentares e tônus muscular normais nos quatro membros e ausência de dor à palpação da coluna cervical. A mielografia revelou atenuação da linha de contraste ventral e dorsal na região da terceira à quinta vértebra cervical. À necropsia, foi observada massa cilíndrica intramedular que se estendia da terceira à sexta vértebra cervical, a qual substituía toda a substância cinzenta da medula espinhal. No estudo histológico, observou-se substituição da substância por manto de células neoplásicas arranjadas frouxamente. As células eram grandes e levemente arredondadas. O citoplasma eosinofílico, bem delineado, por vezes formava processos interligando as células. O núcleo era excêntrico, redondo, oval ou reniforme, e o nucléolo evidente. Logo, as alterações microscópicas observadas na medula espinhal cervical foram compatíveis com astrocitoma gemistocítico.


Palavras-chave: canino, neoplasma, glioma, medula espinhal