February 02, 2011

Spinal tumor

A spinal tumor is a cancerous (malignant) or noncancerous (benign) growth that develops within or near your spinal cord or within the bones of your spine. Although back pain is the most common indication of a spinal tumor, most back pain is associated with stress, strain and aging — not with a tumor.

In most areas of your body, noncancerous tumors aren't particularly worrisome. That's not necessarily the case with your spinal cord, where a spinal tumor or a growth of any kind can impinge on your nerves, leading to pain, neurological problems and sometimes paralysis.
A spinal tumor, whether cancerous or not, can threaten life and cause permanent disability. Yet advances in spinal tumor treatment offer more options than ever before.

Symptoms


Depending on the location and type of tumor, various signs and symptoms can develop, especially as a tumor grows and impinges on your spinal cord or on the nerve roots, blood vessels or bones of your spine. Signs and symptoms may include:
  • Back pain, often radiating to other parts of your body and worse at night
  • Loss of sensation or muscle weakness, especially in your legs
  • Difficulty walking, sometimes leading to falls
  • Decreased sensitivity to pain, heat and cold
  • Loss of bowel or bladder function
  • Paralysis that may occur in varying degrees and in different parts of your body, depending on which nerves are compressed
  • Scoliosis or other spinal deformity resulting from a large, but noncancerous tumor
Back pain, especially in the middle or lower back, is the most frequent symptom of both noncancerous and cancerous spinal tumors. The pain may be worse at night or on awakening. It also may spread beyond your spine to your hips, legs, feet or arms and may become more severe over time in spite of treatment.

Spinal tumors progress at different rates. In general, cancerous tumors grow more quickly, whereas noncancerous tumors may develop very slowly, sometimes existing for years or even decades before causing problems.
When to see a doctor
Most back pain is not the result of a spinal tumor. But because early diagnosis and treatment are important for many back problems, see your doctor about your back pain if:
  • It's persistent
  • It's not activity related
  • It gets worse at night
  • It isn't relieved by over-the-counter analgesics
Seek immediate medical attention if you experience:
  • Progressive muscle weakness or numbness in your legs
  • Changes in bowel or bladder function

Causes


Although scientists are learning more about the genetic and environmental factors involved in the development of many kinds of tumors, spinal tumors are still a relatively unknown quantity. Spinal tumor cells often contain a number of abnormal genes, but in many cases, researchers don't know what causes these genetic alterations. They do know that in some cases, spinal cord tumors run in families and are associated with familial cancer syndromes such as:
  • Neurofibromatosis 2. In this hereditary disorder, noncancerous tumors develop on or near the nerves related to hearing, leading to progressive hearing loss in one or both ears. Some people with neurofibromatosis 2 also develop tumors in the arachnoid layer of the spinal cord or in the supporting glial cells.
  • Von Hippel-Lindau disease. This rare, multisystem disorder is associated with noncancerous blood vessel tumors (hemangioblastomas) in the brain, retina and spinal cord and with other types of tumors in the kidneys or adrenal glands.
It's also known that spinal cord lymphomas — cancers that affect lymphocytes, a type of immune cell — are more common in people whose immune systems are compromised by medications or disease.
Overview of the spine
Your spine provides structural support for your body while at the same time allowing flexible movement. It comprises a complex network of bones, muscles, cartilage, ligaments, joints and nerves. Of these, the vertebrae and spinal cord are the most important for an understanding of spinal tumors:
  • Vertebrae. Your spine is made up of 24 small bones (vertebrae), stacked on top of one another, that enclose and protect the spinal cord and its nerve roots. The sacrum, containing five fused vertebrae, sits below the lower back. The last three tiny vertebrae, also fused together, are called the tailbone (coccyx).
  • Spinal cord. Your spinal cord is a double-layered, long column of nerve fibers that carries messages to and from your brain. The inner layer of your spine contains nerve cells, blood vessels and glial cells, which are cells that support the brain. The outer layer contains nerve fibers (axons) that relay sensory information and conduct motor impulses. Wrapped around the entire spinal cord are three protective membranes (meninges). The inner membrane is called the pia mater, the middle is called the arachnoid, and the tough, outer membrane, to which the spinal nerves attach, is called the dura mater.
Types of spinal tumors
Spinal tumors are classified according to their location in the spine.
  • Extradural (vertebral) tumors. Most tumors that affect the vertebrae have spread (metastasized) to the spine from another site in the body — often the prostate, breast, lung or kidney. Although the original (primary) cancer is usually diagnosed before back problems develop, back pain may be the first symptom of disease in people with metastatic spinal tumors.
    Cancerous tumors that begin in the bones of the spine are far less common. Among these are osteosarcomas (osteogenic sarcomas), the most common type of bone cancer in children, and Ewing's sarcoma, a particularly aggressive tumor that affects young adults. Multiple myeloma is a cancerous disease of the bone marrow — the spongy inner part of the bone that makes blood cells — most commonly seen in older adults.
    Noncancerous tumors, such as osteoid osteomas, osteoblastomas and hemangiomas, also can develop in the bones of the spine where they may cause long-standing pain, spinal curvature (scoliosis) and neurological problems.
  • Intradural-extramedullary tumors. These tumors develop in the spinal cord's arachnoid membrane (meningiomas), in the nerve roots that extend out from the spinal cord (schwannomas and neurofibromas) or at the spinal cord base (filum terminale ependymomas). Meningiomas occur most often in middle-aged women. Although almost always noncancerous, meningiomas can be difficult to remove and may sometimes recur. Nerve root tumors also are generally noncancerous, although neurofibromas can become cancerous over time. Ependymomas at the end of the spinal cord are often large, and their treatment may be complicated by the extensive system of nerves in that area.
  • Intramedullary tumors. These tumors begin in the supporting cells within the spinal cord. Most are either astrocytomas, which mainly affect children and adolescents, or ependymomas — the most common type of spinal cord tumor in adults. Intramedullary tumors can be either noncancerous or cancerous and, depending on their location, may cause numbness, loss of feeling, or changes in bowel and bladder function. In rare cases, tumors from other parts of the body can metastasize to the spinal cord itself.

Complications


Both noncancerous and cancerous spinal tumors can compress spinal nerves, leading to a loss of movement or sensation below the level of the tumor and sometimes to changes in bowel and bladder function. Nerve damage is often permanent, and disabilities are likely to continue even after the tumor is removed. Depending on its location, a tumor that impinges on the spinal cord itself may be life-threatening.

Preparing for your appointment


If you have symptoms that are common to spinal tumors — such as persistent, unexplained back pain, weakness or numbness in your legs, or changes in your bowel or bladder function — call your doctor promptly. After your doctor sees you, he or she may refer to you a doctor who is specially trained to diagnose and treat cancer (oncologist) or brain and spinal cord conditions (neurologist).
Here's some information to help you get ready for your appointment, and what to expect from the doctor.
What you can do
  • Write down any symptoms you've been experiencing, and for how long.
  • List your key medical information, including other conditions with which you've been diagnosed and the names of any prescription and over-the-counter medications you're taking.
  • Note any family history of brain or spinal tumors, especially in a first-degree relative, such as a parent or sibling.
  • Take a family member or friend along, if possible. Sometimes it can be difficult to soak up all the information provided to you during an appointment. Someone who accompanies you may remember something that you missed or forgot.
  • Write down questions to ask your doctor.
Questions to ask your doctor at your initial appointment include:
  • What may be causing my symptoms or condition?
  • Are there any other possible causes?
  • What kinds of tests do I need?
  • What do you recommend for next steps in determining my diagnosis and treatment?
  • Should I see a specialist?
Questions to consider if your doctor refers you to an oncologist or neurologist include:
  • Do I have a spinal tumor?
  • What type of tumor do I have?
  • Is the tumor noncancerous or cancerous?
  • If the tumor is cancerous, how aggressive is it?
  • What are the goals of treatment in my case?
  • Am I a candidate for surgery? What are the risks?
  • Am I a candidate for radiation? What are the risks?
  • What treatment approach do you recommend?
  • If the first treatment isn't successful, what will we try next?
  • What is the outlook for my condition?
  • Do I need a second opinion?
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment at any time that you don't understand something.
What to expect from your doctor
Your doctor is likely to ask you a number of questions. Thinking about your answers ahead of time will help you make the most of your appointment. A doctor who sees you for a possible spinal tumor may ask:
  • What are your symptoms?
  • When did you first notice these symptoms?
  • Have your symptoms gotten worse over time?
  • If you have pain, where does the pain seem to start?
  • Does the pain spread to other parts of your body?
  • Have you experienced any weakness or numbness in your legs?
  • Have you had any difficulty walking?
  • Have you had any problems with your bladder or bowel function?
  • Have you been diagnosed with any other medical conditions?
  • Are you currently taking any over-the-counter or prescription medications?
  • Do you have any family history of noncancerous or cancerous spinal tumors?

Tests and diagnosis


Spinal tumors sometimes may be overlooked because they're rare and because their symptoms resemble those of more common conditions. For that reason, it's especially important that your doctor know your complete medical history and perform both physical and neurological exams. If your doctor suspects a spinal tumor, one or more of the following tests can help confirm the diagnosis and pinpoint the tumor's location:
  • Spinal magnetic resonance imaging (MRI). Instead of radiation, MRI uses a powerful magnet and radio waves to produce cross-sectional images of your spine. MRI accurately shows the spinal cord and nerves and yields better pictures of bone tumors than computerized tomography (CT) scans do. A contrast agent that makes certain tissues and structures light up may be injected into a vein in your hand or forearm during the test. In addition, some medical centers use high-field-strength scanners to find small tumors that might otherwise be missed.
    You may feel claustrophobic inside the scanner or find the loud thumping sound it makes disturbing. But you're usually given earplugs to help with the noise, and some scanners are equipped with televisions or headphones. If you're very anxious, your doctor may prescribe a mild sedative.
  • Computerized tomography (CT). This test uses a narrow beam of radiation to produce detailed, cross-sectional images of your spine. Sometimes it may be combined with an injected contrast dye to make abnormal changes in the spinal canal or spinal cord easier to see. Although not invasive, this test exposes you to more radiation than a regular X-ray does.
  • Myelogram. In this test, a contrast dye is injected into your spinal column. The dye then circulates around your spinal cord and spinal nerves, which appear white on an X-ray or CT scan. Because the test poses more risks than does an MRI or conventional CT, a myelogram is usually not the first choice for diagnosis, but it may be used to help identify compressed nerves.
  • Biopsy. The only way to determine whether a tumor is noncancerous or cancerous is to examine a small tissue sample (biopsy) under a microscope. If the tumor is cancerous, biopsy also helps determine the cancer's grade — information that helps determine treatment options. Grade 1 cancers are generally the least aggressive and grade 4 cancers, the most aggressive. How the sample is obtained depends on your overall health and the location of the tumor. Your doctor may use a fine needle to withdraw a small bit of tissue, or the sample may be obtained during an operation.

Treatments and drugs


Ideally, the goal in treating a spinal tumor is to eliminate the tumor completely, but this aim is complicated by the risk of permanent damage to the surrounding nerves. Doctors also must take into account your age, overall health, the type of tumor and whether it is primary or has spread to your spine.
Treatment options for most spinal tumors include:
  • Monitoring. Sometimes spinal tumors are discovered before they cause symptoms — often when you're being evaluated for another condition. If small tumors are noncancerous and aren't growing or pressing on surrounding tissues, watching them carefully may be the only treatment that you need. This is especially true in older adults for whom surgery or radiation therapy may pose special risks. If you decide not to treat a spinal tumor, your doctor will recommend periodic scans to monitor the tumor's growth.
  • Surgery. This is often the first step in treating tumors that can be removed with an acceptable risk of nerve damage.
    Newer techniques and instruments allow neurosurgeons to reach tumors that were once inaccessible. The high-powered microscopes used in microsurgery make it easier to distinguish tumors from healthy tissue. Doctors also can test different nerves during surgery with electrodes, thus minimizing nerve damage. In some instances, they may use sound waves to break up tumors and remove the remaining fragments.
    Even with advances in treatment, not all tumors can be removed completely. Surgical removal is the best option for many intramedullary and intradural-extramedullary tumors, yet large ependymomas at the end of the spine may be impossible to extricate from the many nerves in this area. Although noncancerous tumors in the vertebrae can usually be completely removed, metastatic tumors are less likely to be operable.
    When a tumor has spread to the spine, radiation alone is usually the treatment of choice. However, research has found that surgery combined with radiation may be more effective at preventing loss of nerve function in people who are healthy enough to tolerate an operation and who have tumors that have spread from an unknown location, have some evidence of nerve injury, have tumors resistant to radiation or have recurrent tumors that were previously irradiated.
    Recovery from spinal surgery may take weeks or months, depending on the procedure, and you may experience a temporary loss of sensation or other complications, including bleeding and damage to nerve tissue.
  • Standard radiation therapy. This may be used following an operation to eliminate the remnants of tumors that can't be completely removed or to treat inoperable tumors. It's also often the first line therapy for metastatic tumors. Radiation may also be used to relieve pain or when surgery poses too great a risk.
    Medications can help some of the side effects of radiation, such as nausea and vomiting. And depending on the type of tumor, your doctor may be able to modify your therapy to help prevent damage to surrounding tissue and improve the treatment's effectiveness. Modifications may range from simply changing the dosage of radiation you receive to using sophisticated techniques that offer better protection to healthy tissue, such as 3-D conformal radiation therapy.
  • Stereotactic radiosurgery (SRS). This newer method, capable of delivering a high dose of precisely targeted radiation, is being studied for the treatment of spinal tumors. In SRS, doctors use computers to focus radiation beams on tumors with pinpoint accuracy, and from multiple angles. This approach has been proved effective in the treatment of brain tumors. Research is under way to determine the best technique, radiation dose and schedule for SRS in the treatment of spinal tumors.
  • Chemotherapy. A standard treatment for many types of cancer, chemotherapy hasn't proved beneficial for most spinal tumors. However, there may be exceptions. Your doctor can determine whether chemotherapy might be beneficial for you, either alone or in combination with radiation therapy.
  • Other drugs. Because surgery and radiation therapy as well as tumors themselves can cause inflammation inside the spinal cord, doctors sometimes prescribe corticosteroids to reduce the swelling, either following surgery or during radiation treatments. Although corticosteroids reduce inflammation, they are usually used for short periods only to avoid such serious side effects as osteoporosis, high blood pressure, diabetes and an increased susceptibility to infection.
Adapted from: Mayo Foundation for Medical Education and Research