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27 Surgical Management of

Spinal Neoplasia

Mark S. Levy

Introduction diagnostics such as three‐view thoracic radiographs, abdominal
Spinal neoplasia is an infrequent diagnosis for the ataxic, paretic, or radiographs, and abdominal ultrasound may also be indicated.
plegic patient. Some patients with spinal neoplasia present with In humans, primary nonlymphoproliferative tumors of the spine
pain as the only sign. Spinal neoplasia can imply tumors associated are uncommon, accounting for less than 5% of bone neoplasms and
with the CNS neuropil, the spinal nerves, peripheral nerves, or the comprising less than 2.5–8.5 primary spine tumors per 100,000
vertebrae. Dogs reportedly have a higher incidence than cats. people per year. Metastatic spinal tumors are much more common.
Nonneoplastic conditions such as intervertebral disc disease are far As many as 40–80% of people are estimated to have skeletal metas-
more common in the dog. Nonneoplastic myelopathies are less tasis, with the spinal column the most common location at the time
common in cats. of death [2].
Spinal tumors occur in all segments of the spinal cord and all of
the vertebral regions. Tumors can be benign or malignant, but all
present with a less than favorable prognosis based on the involve- History
ment of the nervous system. Benign tumors, even though they do One of the most important aspects of diagnosing spinal neoplasia, or
not have the threat of metastasis, can form space‐occupying lesions. for that matter many other abnormalities, is collecting the medical
Metastatic spinal tumors originate in tissues elsewhere and then history. As a general rule, the clinical signs relating to spinal neopla-
spread to the spinal cord region. Even very small tumors can have sia have more of a chronic nature. If signs have been progressing for
devastating consequences within the confines of the spinal cord or more than 2 weeks and steadily worsening, then spinal neoplasia is
vertebral canal. Space‐occupying lesions can also disrupt blood strongly considered as a main differential. The signs caused by the
supply to the cord and cause pain and inflammation. spinal tumor vary and are dependent on many factors: tumor loca-
Spinal tumors are divided into three groups based on their rela- tion, rate of growth, and its effect on spinal stability to name a few.
tive location: extradural, intradural/extramedullary, and intramed- History often contains the answer or at least a short differential.
ullary (Figures 27.1, 27.2 and 27.3). In cats, lymphomas and Things to look for in the history with a patient with spinal neoplasia
meningiomas are more common [1]. In dogs, menigiomas are (i) slow progression of weakness in the limbs (thoracic, pelvic or
(Figure 27.2) are the most common spinal cord tumor and osteosar- both depending on the location of the tumor); (ii) asymmetric weak-
coma is the most common vertebral tumor. Spinal neoplasia can ness and/or muscle mass; (iii) presence of progressive pain experi-
present as an acute or chronic scenario. In general, if a patient has enced by the patient; (iv) increased thirst and/or urination prior to
progressive clinical signs located to the spinal cord for more than a and during these episodes; (v) the lack of presence of pain either
few weeks, spinal neoplasia should be higher on the differential list. steadily or on manipulation/palpation; and (vi) and lack of any his-
An exception to this rule could be degenerative myelopathy in dogs. tory of trauma. While none of these signs are exclusive to spinal neo-
The main factors in assessing the patient with suspicion of spinal plasia, the presence of more than one should lead to higher suspicion.
neoplasia are history, signalment, complete physical examination, In general, age would also be a factor but it does not make for a
and neurological examination. For most patients complete blood definitive differential. Intervertebral disc disease has been reported
work and urinalysis may also be appropriate. Additional basic most commonly in dogs between 3 and 5 years of age. However, a

Current Techniques in Canine and Feline Neurosurgery, First Edition. Edited by Andy Shores and Brigitte A. Brisson.
© 2017 John Wiley & Sons, Inc. Published 2017 by John Wiley & Sons, Inc.
Companion website: www.wiley.com/go/shores/neurosurgery

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