Intramedular Malignant Peripheral Nerve Sheath Tumor at C3 Level in a Dog

Background: Malignant peripheral nerve sheath tumors (MPNSTs) are rare sarcomas in domestic animals, originating from peripheral neural cells or cells associated with the peripheral nerve sheath. These tumors primarily occur in the peripheral nerves of the brachial plexus and may occasionally invade the spinal cord. Diagnosing MPNSTs is challenging owing to the primary clinical sign being progressive claudication, which can be of neurogenic or musculoskeletal origin. Thus, this study aimed to report a case of MPNST located at the C3 level in the vertebral canal, focusing on the clinical, imaging, and surgical aspects of the case. Case: A 9-year-old male mongrel dog, suffering from upper motor neuron tetraparesis, was treated for ataxia and nail dragging on the thoracic limbs. These symptoms later progressed to the pelvic limbs and eventually led to lateral decubitus. Myelotomography revealed a 2 cm neoplasm in the vertebral canal, compressing the spinal cord between the C2-C3 vertebral processes. The patient underwent decompressive surgery via a left dorsal approach to the vertebrae. A hemilaminectomy was performed between C2-C3, removing the laminar bone and exposing the spinal cord and nerve root of the segment. The mass, located in the nerve root region, was carefully separated from adjacent tissues, and removed. The tumor’s histology was consistent with MPNSTs. The patient’s neurological condition, which had been rapidly deteriorating, improved following spinal cord decompression surgery and mass extirpation. After a 3-day hospital stay, the patient was discharged for homecare. Five days post-surgery, the animal exhibited a return of neurological and ambulatory functions. The surgical procedure was the sole treatment method employed against this sarcoma. However, tumor recurrence was observed 270 days post-resection of the mass in the medullary canal. Given the unfavorable prognosis, the animal was euthanized. Discussion: Spinal cord tumors are categorized based on their location and segmentation relative to the spinal cord and dura mater. These categories include intramedullary, intradural-extramedullary, and extradural-extramedullary. Imaging tests such as magnetic resonance imaging (MRI) and computed tomography are more effective in locating and classifying spinal cord tumors than X-rays. Historically, myelography has been utilized to outline the subarachnoid space and ascertain the presence of spinal cord compression or expansion. However, MRI prov