Canine nerve sheath tumors develop in the nervous system. Such growths may be benign or malignant. While the cause of most such tumors are unknown, or idiopathic, they may begin in areas where the dog once suffered an injury. If your dog's tail was docked as a puppy, a nerve sheath tumor might appear there years later. Older dogs are more prone to nerve sheath tumors than young animals.
Nerve Sheath Tumor Symptoms
Dogs suffering from nerve sheath tumors often develop lameness in the front legs and accompanying muscle wasting. These painful tumors also can show up in the hind legs, and in the affected part of the body. You might feel the growth in the affected limb. If the tumor grows in the neck, signs including facial paralysis appear on only one side of the face. Other signs include a drooping eyelid, raised lower lid and smaller pupil. If the dog can reach the area of the tumor, he might continually mutilate the site, since it's causing him discomfort.
Diagnosis and Treatment
Besides considering your dog's physical symptoms, your vet diagnoses a nerve sheath tumor via blood testing and urinalysis, along with either computed tomography scans or magnetic resonance imaging to pinpoint the tumor's location.
Complete removal of the tumor is the treatment of choice, according to the Merck Veterinary Manual. An affected limb may require amputation. After surgery, your vet might recommend radiation and/or chemotherapy for your pet. If the surgeon was able to obtain wide margins when excising the tumor, the prognosis for many dogs is relatively good, provided the tumor has not metastasized. However, if the surgeon was not able to obtain adequate margins when removing the mass, the risk of recurrence is high.