Spinal canal tumors can arise from the tissues covering the spinal cord and are called either exdradural or intradural depending on whether they are on the outside or the inside of the dural membrane which contains the spinal fluid, nerve roots and spinal cord. The intradural tumors are further broken down in to those that are inside the dura but outside the spinal cord, and are referred to as intradural extra-medullary tumors, and those which are inside the spinal cord and are referred to as intradural intra-medullary tumors. The most common types of tumors which are found in the spinal canal, outside the spinal cord are meningiomas and schwannomas and metastatic tumors which most commonly extend from the bone to enter the spinal canal.
Tumors of the spinal canal and spinal cord are usually benign but can also be malignant and may occur as a result of over growth of a cell type that is usually found in the spinal cord tissue. Common types of spinal cord tumors include:
Most spinal canal and spinal cord tumors occur sporadically and do not have particular risk factors. Hemangioblastomas of the spinal cord are a known risk factor in patients with Von Hippel Lindau disease.
Your doctor will ask about your symptoms and medical history. A physical exam will be done. Tests may include:
There are no current guidelines to prevent the formation of spinal tumors.
The approach to spinal tumors is to obtain a working diagnosis to avoid surgery when not needed and employ safe surgical techniques with appropriate neuromonitoring and intraoperative adjuncts to achieve the best result. Patients should have a thorough investigation and work up when they are found to have a spinal abnormality to make sure a tumor diagnosis is not made of the patient has other conditions which can mimic spinal cord tumors such as multiple sclerosis, inflammation, infarction (stroke) of the spinal cord, vascular fistula, or cavernous malformation of the spinal cord.
When surgical treatment is indicated patients will obtain diagnostic studies to properly pinpoint the location of the tumor and plan the extent of the exposure to the tumor which is a laminectomy through a posterior spinal approach in most cases.
Surgical removal of a cervical spinal cord ependymoma using a CO2 Laser. Ependymomas are usually benign tumors of the spinal cord which generally have a good prognosis if they can be completely resected. Like some hemangioblastomas, epenymomas can form a cyst in the spinal cord above and or below the tumor. Figure 3 shows the spinal cord (a) before, (b) during, and (c) after the removal using a CO2 Laser under a high powered microscope.
Laser removal of lumbar schwannoma. Tumors in the intradural space in the lumbar region are most commonly either schwannomas or ependymomas attached to the filum terminale which is a fibrous and vascular structure that comes off of the lower end of the spinal cord. Figure 4 shows a schwannoma (indicated by star) of the lumbar region (a) before, (b) during, and (c) after removal with a CO2 Laser.
Hemangioblastoma of the spinal cord. Hemangioblastomas of the spinal cord are benign tumors which can come to medical attention due to progressive growth and pressure on the spinal cord which can produce symptoms of weakness or numbness of the limbs. These tumors can also sometimes cause a cyst in the spinal cord which is associated with it and usually disappears when the tumor is removed. The surgical removal is performed after a laminectomy and opening of the dura mater which covers the spinal cord and contains spinal fluid. The tumor removal is performed under a high powered microscope using bipolar cautery to shrink the tumor and remove it.
Meningioma of the upper spinal canal. Meningiomas of the spinal canal are most always benign tumors and produce pressure effects on the spinal cord usually causing numbness and weakness which is often slow in onset and progressive in nature. The preferred imaging study is an MRI with and without contrast which shows the tumor very clearly in most cases Figure 2a (left, before surgery) (right, after surgery). The tumor is removed by opening the dura, which covers the spinal cord over the extent of the tumor, to gain access to the upper and lower portion of the tumor. Figure 2b shows tumor to the left (star) and spinal cord to the right with nerve roots crossing behind the tumor before removal. Figure 2c shows the spinal cord to the right after tumor removal.