Four Cases of the Melanotic Variant of Malignant Nerve Sheath Tumour: a Rare, Aggressive Neoplasm in Young Dogs with a Predilection for the Spinal Cord.

Four cases of a rare melanotic variant of malignant nerve sheath tumour (MNST) in dogs are described. All four cases presented with neurological clinical signs due to multicentric, intradural, intra- and extraparenchymal neoplasms that surrounded the spinal and cranial nerves and infiltrated the adjacent spinal cord and brain. The dogs were young (3 months to 3 years of age), all were female and four different breeds were represented.

Anatomic description and clinical relevance of the meningovertebral ligament in dogs.

Objective: To determine whether dogs have a meningovertebral ligament (MVL) and to assess the effect that structure may have on pathological lesions within the ventral epidural space.

Sample: Cadaveric specimens from 6 neurologically normal dogs and 2 dogs with vertebral neoplasms that extended into the epidural space and MRI sequences and cytologic preparations from 2 dogs with compressive hydrated nucleus pulposus extrusion that underwent decompressive surgery.

Procedures: The vertebral column was removed for gross and histologic examination from the cadavers of neurologically normal dogs and dogs with vertebral neoplasms.