Spinal Cord Tumours
(From Merk, Online Medical Manuals)
A spinal cord tumour is a noncancerous (benign) or cancerous (malignant) growth in or around the spinal cord.
· People may have weak muscles, lose sensation in particular areas of the body, or become unable to control bowel and bladder function.
· Magnetic resonance imaging can usually detect spinal cord tumors.
· Treatment may involve surgical removal, radiation therapy, or both.
Spinal cord tumours are much less common than brain tumours. Spinal cord tumours may be primary or secondary.
Primary spinal cord tumors may be cancerous or noncancerous. They may originate in the cells within or next to the spinal cord. Only about 10% of primary spinal cord tumours originate in the cells within the spinal cord. These tumors can extend within the cord and cause a fluid-filled cavity (syrinx) to form.
The other 90% of primary spinal cord tumours originate in cells next to the spinal cord, such as those of the spinal nerve roots—the parts of spinal nerves that emerge from the spinal cord (see Biology of the Nervous System: 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 tumours, which are more common, are metastases of cancer originating in another part of the body and thus are always cancerous. Metastases most commonly spread to the vertebrae from cancers that originate in the lungs, breasts, prostate gland, kidneys, or thyroid gland. Metastases compress the spinal cord or nerve roots from the outside. Lymphomas may also spread to the spine and compress the spinal cord.
Symptoms are caused by pressure on the spinal cord and nerve roots. Pressure on the spinal cord may cause the following:
- Back pain that progressively worsens, is unrelated to activity, and is worse when people lie down
- Decreased sensation, progressive weakness, or paralysis in areas controlled by the parts of the spinal cord below the part that is compressed
- Erectile dysfunction
- Loss of bladder and bowel control
Pressure on the spinal cord may also block the blood supply to the cord, resulting in death of tissue, fluid accumulation, and swelling. Fluid accumulation may block more of the blood supply, leading to 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, 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 tumour must be diagnosed and treated immediately to prevent permanent damage.
Doctors consider the possibility of a spinal cord tumour in people who have certain cancers in other parts of the body, who develop pain in a specific area of the spine, and who have certain patterns of weakness or tingling. Because the spinal cord is organized in a specific way, doctors can locate the tumour by determining which parts of the body are not functioning normally
Doctors must rule out other disorders that can affect the function of the spinal cord, such as sore back muscles, bone bruises, an inadequate blood supply to the spinal cord, fractured vertebrae, compression by a collection of pus (abscess), a blood clot, or a herniated disk.
Several procedures can help doctors diagnose a spinal cord tumour. 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 can show only changes in the bones, and many tumours do not affect the bone when they are in an early stage.
A biopsy is usually needed to diagnose the precise type of tumour, especially primary spinal cord tumours. However, a biopsy is not needed for spinal cord tumours 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 computed tomography (CT) or MRI to guide doctors as they place the needle in the tumour.
If symptoms suggest that the tumour is compressing the spinal cord, corticosteroids (such as dexamethasone) are immediately given in high doses to reduce the swelling. Such tumours are treated as soon as possible, often surgically.
Many tumors of the spinal cord and spine can be removed surgically. If tumours cannot be removed, radiation therapy is used, sometimes after surgery to relieve the pressure on the spinal cord is done.
Recovery generally depends on how quickly treatment begins and how much damage was done. Removal of meningiomas, neurofibromas, and some other primary spinal cord tumours may be curative.