Central nervous system metastasis of an intradural malignant peripheral nerve sheath tumour in a dog

Abstract

An 8-year-old French Bulldog was presented with a nonambulatory tetraparesis. Magnetic Resonance showed an intradurally located mass at the level of the right second cervical nerve root. The mass was surgically removed and the dog was ambulatory within four days. A ten-month post-surgical imaging follow up revealed a recurrence of the primary mass and another intradural/intramedullary mass at the level of the first thoracic vertebral body. Overall histological features were suggestive of malignant peripheral nerve sheath tumour for both masses. Immunohistochemistry was found weakly but diffusely positive for S-100 and NSE for both masses. A diagnosis of primary malignant peripheral nerve sheath tumour for the cervical mass and of metastasis for the thoracic mass was made, possibly disseminated via the subarachnoidal space. To our knowledge, central nervous system metastasis of malignant peripheral nerve sheath tumours have not previously been reported in dogs. The clinician should be aware that these tumours, albeit rarely, can metastasize to the central nervous system.

Keywords

• Central nervous system metastasis
• Dog
• Malignant peripheral nerve sheath tumour