Neuro-Ophthalmology & Neuro-Otology
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Jul. 25, 2020
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A diagnosis of a brain or spinal cord tumor brings uncertainty and worry to you and your friends and family. It’s easy to become overwhelmed by a new world of tests, technology, and treatments that you may know little or nothing about.
This handout will give you a better understanding of brain and spinal cord tumors, their treatment options, and the latest research to find safer, more effective ways to diagnose and treat them. You can take the best care of yourself by learning about your diagnosis and discussing it with your doctors.
What are brain and spinal cord tumors?
Brain and spinal cord tumors are found in the tissue inside the skull or the bony spinal column, which makes up the central nervous system (CNS). A tumor is a mass of cells that forms a new growth or is present at birth (congenital). Tumors occur when genes that regulate cell growth become damaged or mutated, allowing cells to grow and divide out of control. Tumors can form anywhere in the body.
Depending on the type, a growing tumor can kill healthy cells or disrupt their function. It can move or press on sensitive tissue and block the flow of blood and other fluid, causing pain and inflammation. A tumor can also block the normal flow of electricity in the brain or nerve signaling to and from the brain. Some tumors cause no trouble at all.
There are more than 120 types of brain and spinal cord tumors. Some are named by the type of cell in which they start (such as glioma) or location (such as meningioma, which form in the lining of the brain and spinal cord).
What are benign and malignant tumors?
No matter where they are located in the body, tumors are classified as benign or malignant.
Benign tumors are slow growing, non-cancerous cell masses that have a defined edge and do not spread to other parts of the body. Cells in the tumor are similar to normal cells. Often these tumors can be removed surgically and usually do not recur.
Malignant, or cancerous, tumors have cells that look different from normal cells. They can quickly invade surrounding tissue and often have edges that are hard to define, which makes it difficult to remove the entire tumor surgically.
What are primary and metastatic tumors?
Primary tumors of the CNS are growths that begin in the brain or spinal cord. They can be either malignant or benign and are identified by the types of cells they contain, their location, or both. Most primary CNS tumors occur in adults.
Metastatic, or secondary, tumors in the CNS are caused by cancer cells that break away from the primary tumor that developed in a non-CNS part of the body. These tumors are named after the type of cancer that causes them. Metastastic tumors (also called metastases) to the brain occur in about one-fourth of all cancers that develop in other parts of the body, such as cancer of the lung, breast, or kidneys; or melanoma, a form of skin cancer. They are more common than primary tumors and occur more often in adults than in children.
Metastatic spine tumors usually form within the bony covering of the spinal column but may also invade the spinal canal from the chest or abdomen.
While cancers elsewhere in the body can easily cause tumors inside the brain and spinal cord, CNS tumors rarely spread outside the nervous system.
What causes CNS tumors?
Researchers really don't know why primary brain and spinal cord tumors develop. Possible causes under investigation include viruses, defective genes, exposure to certain chemicals and other hazardous materials, and immune system disorders. Although smoking, alcohol consumption, and certain dietary habits are associated with some types of cancers, they have not been linked to primary CNS tumors.
In a small number of individuals, CNS tumors may result from specific genetic diseases, such as neurofibromatosis and tuberous sclerosis, or exposure to radiation. Non-ionizing radiation (radio waves) from mobile phone use does not increase the risk of developing a brain tumor.(1)
Brain and spinal cord tumors are not contagious or, at this time, preventable.
Who is at risk?
Anyone can develop a primary CNS tumor, although the risk is very small. Having one or more of the known risk factors does not guarantee that someone will develop a tumor. Brain tumors occur more often in males than in females and are most common in middle-aged to older persons. They also tend to occur more often in children under age 9 than in other children, and some tumors tend to run in families. Most brain tumors in children are primary tumors.
Other risk factors for developing a primary CNS tumor include race (Caucasians are more likely to develop a CNS tumor than other races) and occupation. Workers in jobs that require repeated contact with ionizing radiation or certain chemicals, including those used to manufacture building supplies or plastics and textiles, have a greater chance of developing a brain tumor.
How many people have these tumors?
More than 359,000 persons in the United States are estimated to be living with a diagnosis of primary brain or central nervous system tumor.(2) More than 195,000 Americans are diagnosed with a brain tumor each year.(3) Brain tumors are the most common form of solid tumor in children.
Spinal cord tumors are less common than brain tumors. Although they affect people of all ages, spinal cord tumors are most common in young and middle-aged adults. Nearly 3,200 central nervous system tumors are diagnosed each year in children under age 20.(4)
How are tumors graded?
The generally accepted scale for grading CNS tumors was approved by the World Health Organization in 1993. Grading is based on the tumor’s cellular makeup and location. Tumors may also be classified as low-grade (slowly growing) or high-grade (rapidly growing). Some tumors change grades as they progress, usually to a higher grade, and can become a different type of tumor. The tumor is graded by a pathologist following a biopsy or during surgery.
Grade I tumors grow slowly and generally do not spread to other parts of the brain. It is often possible to surgically remove an entire grade I benign tumor, but this type of tumor may be monitored periodically, without further treatment.
Grade II tumors also grow slowly, sometimes into surrounding tissue, and can become a higher-grade tumor. Treatment varies according to tumor location and may require chemotherapy, radiation, or surgery followed by close observation.
Grade III tumors are malignant and can spread quickly into other CNS tissue. Tumor cells will look different than those in surrounding tissue. Aggressive treatment, often using a combination of chemotherapy, radiation, and/or surgery, is required.
Grade IV tumors invade nearby tissue very quickly and are difficult to treat. The cancerous tissue will look very different from surrounding tissue. Aggressive treatment is required.
What are the possible symptoms?
Brain and spinal cord tumors cause many diverse symptoms, which can make detection tricky. Symptoms depend on tumor type, location, size, and rate of growth. Certain symptoms are quite specific because they result from damage to particular areas of the brain. Symptoms generally develop slowly and worsen as the tumor grows.
The most obvious sign of a brain tumor in infants is a rapidly widening head or bulging crown.
Common symptoms of a brain tumor in adults include headaches, seizures, problems with balance or coordination, loss of muscle control, hydrocephalus, and changes in personality or behavior.
Headaches are the most common symptom of a brain tumor. Headaches may progressively worsen, become more frequent or constant, and recur, often at irregular intervals. Headache pain may worsen when coughing, changing posture, or straining and may be severe upon waking.
Seizures can occur, with symptoms that may include convulsions, loss of consciousness, or loss of bladder control. Seizures that first start in adulthood (in someone who has not been in an accident or who had an illness that causes seizures) are a key warning sign of brain tumors.
Nausea and vomiting may be more severe in the morning and may accompany headaches.
Vision or hearing problems can include blurred or double vision, partial or total loss of vision or hearing, ringing or buzzing sounds, and abnormal eye movements.
Personality, behavior, and cognitive changes can include psychotic episodes and problems with speech, language, thinking, and memory.
Motor problems can include weakness or paralysis, lack of coordination, or gradual loss of sensation or movement in an arm or leg. A sudden, marked change in handwriting may be a sign of a tumor.
Balance problems can include dizziness, trouble with walking, clumsiness, or loss of the normal control of equilibrium.
Hydrocephalus and increased intracranial pressure are caused when a tumor blocks the flow of the cerebrospinal fluid (CSF) that surrounds the brain and spinal cord. Symptoms may include headaches, nausea, and vomiting.
Other symptoms may include endocrine disorders or abnormal hormonal regulation, difficulty swallowing, facial paralysis and sagging eyelid, fatigue, weakened sense of smell, or disrupted sleep and sleep pattern changes.
Common symptoms of a spinal cord tumor include pain, numbness or sensory changes, and motor problems and loss of muscle control.
Pain can feel as if it is coming from various parts of the body. Back pain may extend to the hips, legs, feet, and arms. This pain is often constant and may be severe. It is often progressive and can have a burning or aching quality.
Numbness or sensory changes can include decreased skin sensitivity to temperature and progressive numbness or a loss of sensation, particularly in the legs.
Motor problems and loss of muscle control can include muscle weakness, spasticity (in which the muscles stay stiffly contracted), and impaired bladder and/or bowel control. If untreated, symptoms may worsen to include muscle wasting, decreased muscle strength, an abnormal walking rhythm known as ataxia, and paralysis.
Symptoms may spread over various parts of the body when one or more tumors extend over several sections of the spinal cord.
How are CNS tumors diagnosed?
A doctor, usually a neurologist, oncologist, or neuro-oncologist, can confirm a diagnosis of a brain or spinal cord tumor based on a patient’s symptoms, personal and family medical history, and results of a physical exam and specialized tests and techniques.
A neurological exam—the first test—assesses movement and sensory skills, hearing and speech, reflexes, vision, coordination and balance, mental status, and changes in mood or behavior, among other abilities. Some tests require a specialist to perform and analyze results.
Diagnostic imaging. The doctor will order one or more imaging techniques that show extremely detailed views of body structures, including tissues, organs, bones, and nerves. If there is a tumor, diagnostic imaging will confirm the diagnosis and help doctors determine the tumor's type, detect swelling and other associated conditions, and, over time, check the results of treatment.
Computed Tomography (CT) uses x-rays and a computer to produce fast, detailed cross-sectional images or “slices” of organs, bones, and tissues, including a tumor. It is also good for detecting the buildup of calcium, which causes tissue to harden and can develop into a tumor.
Magnetic Resonance Imaging (MRI) uses a computer, radio waves, and a strong magnetic field to produce two-dimensional slices or a detailed three-dimensional model of tissue being scanned. MRI takes longer to perform than does a CT but is more sensitive and gives better pictures of tumors located near bone.
Both CT and MRI scans for tumor are usually performed before and after administration of a "contrast" agent (such as a dye) that is given into a vein. Many tumors become much brighter on the scan taken after the contrast is given.
Functional MRI (fMRI) creates images of areas of the brain with specific functions such as movement and language. It can assess brain damage from head injury or degenerative disorders, identify and monitor other neurological disorders such as stroke, and show the distance between specific brain functions and tumors in particular areas of the brain.
Magnetic Resonance Spectroscopy (MRS) gives doctors a chemical snapshot of tissues being studied. It uses the MRI scanner's magnetic field and radio waves to measure and analyze the chemical make-up of the tissue sample.
Positron Emission Tomography (PET) provides computer-generated two- and three-dimensional scans of the brain’s chemical activity and cellular function. PET traces and measures the brain’s use of glucose (sugar, used by the brain for energy) that is attached to small amounts of radioactivity and injected into the bloodstream. Since malignant tissue uses more glucose than normal tissue, it usually shows up on the scan as brighter than surrounding tissue.
Single Photon Emission Computed Tomography (SPECT) studies blood flow to tissue. Certain tumors grow new blood vessels to increase their supply of blood and nutrients. A radioactive isotope is injected intravenously and traced as it travels into the skull. A sophisticated computer processes and stacks the data into a detailed three-dimensional image of activity within the brain.
Angiography (or arteriogram) can distinguish certain types of tumors that have a characteristic pattern of blood vessels and blood flow. A dye that deflects x-rays is injected into a major blood vessel and a series of x-rays is taken as the dye flows to the brain. In many situations angiography has been replaced by non-invasive tests such as CT and MRI.
Laboratory tests. Testing blood, urine, and other substances can provide clues about the tumor and monitor levels of therapeutic drugs.
Additional tests may include an electroencephalogram, or EEG, which monitors brain activity through the skull (tumors can disrupt the normal flow of brain wave activity and cause seizures); CSF analysis, in which a small amount of the cerebrospinal fluid is removed by a special needle and examined for abnormal cells or unusual levels of various compounds that suggest a brain or spinal cord tumor; and magnetoencephalography (MEG), which studies brain function by measuring the magnetic field generated by nerve cells in the brain. CSF fluid analysis should be performed with extreme caution on individuals with very large brain tumors.
Diagnosing the distinct type of brain tumor is often difficult. Individuals should consider asking their primary care physician or oncologist for a second opinion, particularly from a neuro-oncologist or neurosurgeon, as there may be new information available and some tumors can change grade or recur. Even a second opinion that confirms the original diagnosis can help people better prepare for their care and treatment.
How are brain and spinal cord tumors treated?
A specialized team of doctors advises and assists individuals throughout treatment and rehabilitation. These doctors may include:
• A neurologist is a specialist in nervous system disorders.
• A medical oncologist is a specialist in cancer.
• A neuro-oncologist is a neurologist who specializes in nervous system tumors.
• A neuroradiologist is a doctor trained in reading diagnostic imaging results who specializes in the CNS.
• A pathologist is a clinical physician who diagnoses diseases of tissues or cells using a variety of laboratory tests.
• A neurosurgeon is a brain or spinal cord surgeon.
• A radiation oncologist is a doctor who specializes in using radiation to treat individuals with cancer.
This team will recommend a treatment plan based on the tumor's location, type, size and aggressiveness, as well as on the individual’s medical history, age, and general health.
Initial treatment for a CNS tumor may involve a variety of drugs, including anticonvulsants to treat seizures, pain medications, steroids or other anti-inflammatory drugs to reduce swelling and improve blood flow, antidepressants to treat anxiety or ease depression that might occur following a tumor diagnosis, and drugs to fight nausea caused by various treatments.
Malignant tumors require some form of treatment, while some small benign tumors may need only periodic monitoring. The three standard treatment options for malignant CNS tumors are neurosurgery, radiation therapy, and chemotherapy. Some patients may receive a combination of treatments.
What is the prognosis?
Each person is different. Prognosis depends greatly on prompt diagnosis and treatment, the individual’s age and general health, whether the tumor is malignant or benign, tumor size and location, tumor grade, and response to therapy. An individual whose entire tumor has been removed successfully may recover completely. Generally, prognosis is poorer in very young children and in older individuals. Rehabilitation and counseling can help patients and family members better cope with the disorder and improve quality of life.
Continued monitoring and long-term follow-up is advised as many tumors resist treatment and tend to recur.
Normal tissue and nerves that may have been damaged or traumatized by the tumor or its treatment will need time to heal. Some post-treatment symptoms will disappear over time. Physical therapy can help people regain motor skills, muscle strength, and balance. Some individuals may need to relearn how to swallow or speak if the brain’s cognitive areas have been affected. Occupational therapy can teach people new ways to perform tasks. Supportive care can help people manage any pain and other symptoms.
Where can I find more information?
For information on other neurological disorders or research programs funded by the National Institute of Neurological Disorders and Stroke, contact the Institute's Brain Resources and Information Network (BRAIN) at:
P.O. Box 5801
Bethesda, MD 20824
A number of private voluntary organizations also offer information and services to those affected by brain and spinal cord tumors. Their names and adresses are provided below.
American Brain Tumor Association (ABTA)
8550 W Bryn Mawr Ave, Suite 550
Chicago, IL 60631
773-577-8750 / 800-886-2282
American Cancer Society
National Home Office
250 Williams Street, NW
Atlanta, GA 30303-1002
National Brain Tumor Society
124 Watertown Street , Suite 2D
Watertown, MA 02472-2500
617-924-9997 / 800-770-TBTS (8287)
Children's Brain Tumor Foundation
274 Madison Avenue, Suite 1004
New York, NY 10016
212-448-9494 / 866-CBT-HOPE (228-4673)
National Brain Tumor Foundation (NBTF)
124 Watertown St, Suite 2D
Watertown, MA 02472
415-834-997 0/ 800-934-CURE (2873)
Musella Foundation for Brain Tumor Research and Information
1100 Peninsula Blvd.
Hewlett, NY 11557
Tel: 516-295-4740 / 888-295-4740
This information was developed by the National Institute of Neurological Disorders and Stroke, National Institutes of Health.
National Institute of Neurological Disorders and Stroke. Brain and Spinal Cord Tumors - Hope Through Research. Available at: https://www.ninds.nih.gov/disorders/brainandspinaltumors/detail_brainandspinaltumors.htm. Accessed January 3, 2014.
The information in this document is for general educational purposes only. It is not intended to substitute for personalized professional advice. Although the information was obtained from sources believed to be reliable, MedLink Corporation, its representatives, and the providers of the information do not guarantee its accuracy and disclaim responsibility for adverse consequences resulting from its use. For further information, consult a physician and the organization referred to herein.