The spinal cord, which lies protected inside the spine (backbones), contains bundles of nerves that transmit messages between the brain and the nerves throughout the body. A tumor on or near the spinal cord can disrupt this communication, impair function and seriously threaten health.
Spinal cord tumors are masses of abnormal cells that grow in the spinal cord, between its protective sheaths, or on the surface of the sheath that covers the spinal cord. About 10,000 people in the United States develop spinal cord tumors each year. Most noncancerous tumors develop within the spinal cord rather than spreading from other parts of the body. These are called primary tumors, and they usually are noncancerous (benign). Primary spinal cord cancers rarely spread to other parts of the body. This is unusual, which has made spinal cord cancers a focus of scientific investigation; their unique qualities may suggest new methods of cancer prevention or treatment.
Most cancerous spinal cord tumors are secondary, meaning they spread from a cancer at another site of the body. One in every four people whose cancer has spread throughout the body has had it spread to the brain or spinal cord. These secondary tumors most frequently result from lung, prostate or breast cancer.
Spinal cord tumors can affect people of all ages, but are seen most commonly in young and middle-aged adults.
Doctors divide spinal cord tumors into three major groups based on their location:
- Extradural tumors grow outside of the dura mater (the membrane that protects the spinal cord) and are usually in the bones surrounding the spinal cord. Most spinal cord tumors are extradural.
- Intradural-extramedullary tumors grow outside the spinal cord and within the dura mater.
- Intramedullary tumors grow inside the spinal cord itself.
Spinal cord tumors generally develop slowly and worsen over time. They can cause many symptoms depending upon their location. Symptoms arise as the tumor presses on the spinal cord or the nerves that exit it. Tumors also may restrict the flow of blood to the spinal cord. Common symptoms include:
- Pain. Back pain is usually the most prominent symptom, but pressure on the spinal cord can trigger pain that feels as if it is coming from various parts of the body. This pain is sometimes severe, is often constant and can have an aching or burning quality.
- Sensory changes. These can take the form of numbness, tingling, decreased sensitivity to temperature or cold sensations.
- Motor problems. Tumors that hinder nerve communication can cause muscle-related symptoms, such as progressive muscle weakness or loss of control over the bowel or bladder.
The part of the body affected by the symptoms will vary depending on the tumor's location on the spinal cord. In general, symptoms occur in parts of the body that are at the same level as or lower than the tumor.
If you have any of the symptoms of a spinal cord tumor, your doctor will examine you and review your medical history for other conditions that may cause similar symptoms. The physical exam will include a standard neurological examination, which checks eye movement, eye reflexes and pupil reaction; reflexes; hearing; sensation; strength; and balance and coordination.
If your doctor suspects that you may have a spinal tumor, he or she may recommend x-rays of the spine and other diagnostic tests, including:
Computed tomography (CT) scan. Computed tomography can determine the location of the tumor on the spinal cord, and also can help to detect swelling, bleeding and other associated conditions. The technique creates a cross-sectional view of the body's tissue and structure using a computer and an X-ray camera that rotates around the body. A dye sometimes is injected into a vein before the scan to help show differences between tissues, which makes it easier to see the tumor.
Magnetic resonance imagining (MRI) scan. This technique gives a picture of the spinal cord using a powerful magnet, a radiowave transmitter and a computer. It can provide better pictures of tumors near bone than computed tomography.
Myelogram. This is a specialized X-ray technique in which a dye that absorbs X-rays is injected into the spinal cord. The dye outlines the spinal cord, but will not pass through the tumor, creating an image with a dark or narrowed area that indicates the tumor's location. Myelograms are done only occasionally because MRI provides similar information and does not require a spinal injection.
Lumbar puncture. This procedure removes a sample of cerebrospinal fluid, which is tested for abnormal cells that may suggest the presence of a spinal cord tumor.
- Biopsy. A sample of the tumor may be removed and examined under a microscope to confirm the diagnosis and rule out other conditions. However, it can be difficult to obtain a biopsy of a spinal cord tumor without damaging the spinal cord so careful planning and imaging (such as MRI or CT scan or both) are important. In many cases (especially when a person is known to have cancer already), treatment of the spinal cord tumor may not require a biopsy.
Once it develops, a spinal cord tumor usually will continue to grow until it is treated. Without treatment, it can lead to permanent paralysis, significant disability and death.
Although spinal cord tumors cannot be prevented, some forms of cancer that spread to the spinal cord can be prevented or cured before they can spread to the spine. Examples including lung cancer, which may be prevented by not smoking, and breast cancer, which may be cured if detected early through appropriate screening. While some benign tumors can occur more often in certain families, the cause of primary spinal cord tumors remains a mystery. Possible causes under investigation include defective genes, viruses and exposure to chemicals.
Surgery usually is recommended for noncancerous and cancerous primary spinal cord tumors, and usually is successful for tumors located outside the spinal cord. However, other tumors may be impossible to remove without significantly damaging the spinal cord. In those cases, radiation therapy may be used to slow the tumor's growth. Surgical removal of surrounding vertebrae can also help to relieve pain and other symptoms by reducing pressure on the spinal nerves. Chemotherapy may be recommended for certain types of tumors, usually after surgical treatment.
For secondary tumors, the treatment will depend upon the type of cancer that has spread to the spinal cord. However, radiation is regarded as a primary treatment for secondary cancer that is compressing the spinal cord. With radiation therapy, care must be taken to limit possible damage to surrounding normal spinal tissue, because such damage can continue to worsen and can be irreversible. The spinal cord is even more sensitive to the effects of radiation than brain tissue. In particular, the thoracic spinal cord segments in the area of the ribs -- where about half of all spinal cord tumors occur -- are the most sensitive to radiation's effects.
With all types of spinal cord tumors, corticosteroid drugs also may be prescribed to reduce spinal cord swelling. In addition, physical therapy may be needed to help a person regain muscle control and strength after radiation or surgery.
Back pain is a common problem and is rarely a sign of cancer. However, call your doctor for an evaluation of persistent or worsening back pain, especially if it keeps you awake at night. If you experience any numbness, tingling or weakness, call your doctor for an evaluation right away. This is particularly important for people who have had cancer in the past.
The prognosis will depend upon the location of the tumor on the spinal cord, the type of tumor and the size of the tumor at the time of diagnosis. Early diagnosis and treatment are vital to restoring function and preventing permanent damage to the spinal cord.
National Institute of Neurological Disorders and Stroke
American Brain Tumor Association
2720 River Road
Des Plaines, IL 60018
Children's Brain Tumor Foundation
274 Madison Ave.
New York, NY 10016
Brain Tumor Society
124 Watertown St.
Watertown, MA 02472