In general, spinal cord tumors (intradural tumors) are classified based on their location as related to the spinal cord (medullary) as extramedullary or intramedullary.

Intradural intramedullary tumors are within the spinal cord nerves, whereas extramedullary tumors are within the spinal canal but outside of the nerves. Extramedullary tumors are usually slow-growing and benign, but can cause pain and weakness. These tumors represent 2–4% of all tumors of the central nervous system (CNS).

Most extramedullary spinal tumors are:

  • Meningiomas occurring in the membranes surrounding the spinal cord and can be benign (more commonly) or malignant. These tumors are more common in middle age and elderly women.
  • Nerve sheath tumors– arise from the nerve roots that come off the spinal cord.
  • Metastases which have been caused by cancer found elsewhere in the body.

Intramedullary tumors grow from inside the spinal cord or inside the individual nerves. Intramedullary tumors are comprised predominantly of gliomas (infiltrative astrocytomas and ependymomas). These tumors are most often found in the cervical spinal cord (neck). Most intramedullary tumors are benign.
Tumors within the spinal cord generally cause detectable symptoms, while spinal column tumors outside of the cord may develop for some time before symptoms emerge. Common symptoms include:

  • Back pain
  • Cold sensation in the legs, feet or hands
  • Loss of bowel control
  • Loss of sensation, particularly in the legs
  • Muscle weakness and difficulty walking
  • Muscle contractions or spasms

In many cases, conventional or image-guided surgery may both be performed in conjunction with stereotactic radiosurgery to treat a patient with a spinal cord tumor.

Traditional, respective surgery can usually be accomplished with spinal ependymomas due to separation of the tumor from the spinal cord and, when complete, requires no further therapy. By contrast, spinal cord gliomas infiltrate the myelon and, consequently, surgery is nearly always incomplete. In these cases, Dr. Karahalios utilizes an innovative piece of technology, Novalis TX, to precisely radiate the remaining tumor without harming the surrounding healthy tissue.

Extramedullary tumors are primarily peripheral nerve sheath tumors (neurofibromas or schwanommas) or meningiomas. In either instance, surgical removal of the tumor in many cases is possible and is often curative. In these cases, stereotactic radiosurgery is reserved for rare malignant tumors and for patients in whom surgery is contraindicated.

In general, surgery consists of removing all or as much of the tumor as possible to relieve pressure (decompress) on the spinal cord.
In those cases where total removal of the spinal cord tumor is not possible, or for patients where traditional surgery is not indicated, stereotactic radiosurgery delivered by a specialized device such as the Novalis system may be used to reduce the pain and control the growth of the tumor. Radiosurgery may also be considered in some cases of asymptomatic tumors where a non-invasive approach is preferred.

More specifically, stereotactic spine radiosurgery involves the precise delivery of high doses of radiation to tumors of the spinal cord that limits the radiation exposure to normal surrounding structures. Novalis is a form of knifeless surgery that uses a precalculated amount of radiation targeted to match a tumor’s shape. This helps spare healthy tissue from radiation and can eliminate side effects commonly associated with standard radiation therapy. Amazingly, within a few weeks of just one Novalis treatment — lasting only about 30 minutes — a spinal cord tumor may be visibly smaller. Full effects of Novalis treatment can be gauged after three months of treatment. Spine radiosurgery is an important part of the multidisciplinary treatment of patients with spinal cord tumors. Dr. Karahalios has nearly ten years of experience using stereotactic radiosurgery to treat his patients with spinal cord tumors and has seen excellent results.