(See also Overview of Tumors of the Nervous System.)
Spinal cord tumors are much less common than brain tumors. Spinal cord tumors may be
Primary spinal cord tumors may be cancerous or noncancerous.
Primary spinal cord tumors may originate in the cells within or next to the spinal cord. Only about one third of primary spinal cord tumors originate in the cells within the spinal cord. These tumors can extend within the cord, block the flow of cerebrospinal fluid (the fluid that surrounds the brain and spinal cord), and cause a fluid-filled cavity (syrinx) to form.
Most primary spinal cord tumors originate in cells next to the spinal cord, such as those of the meninges—the layers of tissue that cover the spinal cord (see figure How the Spine Is Organized).
Meningiomas and neurofibromas, which originate in cells next to the cord, are the most common primary spinal tumors. They are noncancerous.
Secondary spinal cord tumors, which are more common, are metastases of cancer originating in another part of the body and thus are always cancerous. These metastases typically spread to bones in the spine (vertebrae) and the space between the bone and the outer layer of tissue around the spinal cord (epidural space). Sometimes these tumors spread to the spinal cord. Metastases most commonly spread to the vertebrae from cancers that originate in other parts of the body. These cancers include:
Metastases usually put pressure on (compress) the spinal cord or nerve roots from the outside. Many of these tumors invade and destroy bone before they compress the spinal cord.
Most spinal cord tumors that are located in the cells next to the spinal cord (rather than within it) are metastatic.
Primary Tumors That Originate in or Near the Spinal Cord*
Symptoms are caused by pressure on the spinal cord and nerve roots. Pressure on the spinal cord may cause the following:
Pressure on the spinal cord may also block the blood supply to the cord, resulting in death of tissue and swelling. The swelling may block more of the blood supply, leading to more tissue death in a vicious circle of damage. Symptoms due to pressure on the spinal cord can worsen quickly.
Pressure on spinal nerve roots can cause pain, numbness, tingling, and weakness in areas supplied by the compressed nerve root. Pain may radiate along the nerve whose root is compressed. If compression continues, the affected muscles may waste away. Walking may become difficult.
Compression of the spinal cord by a tumor must be diagnosed and treated immediately to prevent permanent damage.
Doctors consider the possibility of a spinal cord tumor in people who have certain patterns of weakness or nerve dysfunction (such as loss of sensation) or pain in certain locations in the back or neck, particularly if they have certain cancers in other parts of the body.
Because the spinal cord is organized in a specific way, doctors can locate the tumor by determining which parts of the body are not functioning normally.
When doctors suspect a spinal tumor, they must rule out other disorders that can affect the function of the spinal cord, such as a herniated disk, injuries, demyelination (damage to the tissues that cover nerves) and inflammation of the spinal cord, an inadequate blood supply to the spinal cord, or compression of the spinal cord by a pocket of pus (abscess) or blood clot.
Several procedures can help doctors diagnose a spinal cord tumor. Magnetic resonance imaging (MRI) is considered the best procedure for examining all the structures of the spinal cord and spine. When MRI is unavailable, myelography with computed tomography (CT) may be done instead.
X-rays of the spine are less useful because they show only changes in the bones. However, x-rays, taken for other reasons, may detect destruction of the bone or distortion of the tissues around the spinal cord, especially if the tumor is metastatic.
A biopsy is sometimes needed to diagnose the precise type of tumor, especially primary spinal cord tumors. However, a biopsy is not needed for spinal cord tumors that result from metastases if cancer has been diagnosed elsewhere in the body. Often, a biopsy requires surgery, but sometimes it can be done using a needle with CT or MRI to guide doctors as they place the needle in the tumor.
If symptoms suggest that the tumor is compressing the spinal cord, corticosteroids (such as dexamethasone) are immediately given in high doses to reduce the swelling. Such tumors are treated as soon as possible, often surgically.
Many tumors of the spinal cord and spine can be removed surgically. In some cases, radiation therapy is given after surgery.
If tumors cannot be removed, radiation therapy is used, sometimes after surgery has been done to relieve the pressure on the spinal cord.
Other treatments, such as chemotherapy, may be used depending on the type of cancer.
Recovery generally depends on how quickly treatment begins and how much damage was done. Removal of meningiomas, neurofibromas, and some other primary spinal cord tumors may result in a cure. If a tumor has distinct borders and has not spread from elsewhere in the body, removing it causes symptoms to resolve in about half of people.