Brain Tumor Glossary of Terms

Easily explore the meaning of hundreds of medical terms or words, many directly used in brain tumor-related terminology.

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Gamma Irradiation

A type of radiation therapy that uses gamma radiation. Gamma radiation is a type of high-energy radiation that is different from x-rays.

Gamma knife

Gamma knife. A special multi-source irradiation machine which focus a high intensity of irradiation on a small area: it is used as local therapy in especially brain tumors.

Gamma knife surgery

This is also known as radiosurgery. With regular radiation therapy a standard external beam is used. Tumors and much , or all, of the surrounding brain are treated to the same dose of radiation. Gamma Knife radiosurgery treats only the abnormal tissues. This treatment occurs in a single session without significant radiation to the adjacent brain. Click here for more information.

Gamma Knife Therapy

A treatment using gamma rays, a type of high-energy radiation that can be tightly focused on small tumors or other lesions in the head or neck, so very little normal tissue receives radiation. The gamma rays are aimed at the tumor from many different angles at once, and deliver a large dose of radiation exactly to the tumor in one treatment session. This procedure is a type of stereotactic radiosurgery. Gamma Knife therapy is not a knife and is not surgery. Gamma Knife is a registered trademark of Elekta Instruments, Inc.

Gamma Ray

A type of high-energy radiation that is different from an x-ray.

Ganglia

Ganglia, basal: A region located at the base of the brain composed of 4 clusters of neurons, or nerve cells. This area of the brain is responsible for body movement and coordination. The groups of neurons most prominently and consistently affected in Huntington disease -- the pallidum and striatum -- are located in the basal ganglia. (The pallidum is composed of structures called the globus pallidus and the ventral pallidum while the striatum consists of the caudate nucleus, putamen, and ventral striatum.) The term "basal ganglia" refers to the location of these collections of neurons (ganglia) deep within the brain, seemingly at its very base.

Ganglion brain tumors

Rare, benign tumors arising from ganglia-type cells, which are groups of nerve cells. Tumors arising from ganglia most frequently occur in children and young adults. These tumors are small, slow growing, and have distinct margins. Metastasis and malignancy are very rare.

Synonyms: 1. Swelling, one of the cardinal signs of inflammation; morbid enlargement. 2. A new growth of tissue in which the multiplication of cells is uncontrolled and progressive. Also called neoplasm.Tumor calcification, A benign tumor of epithelium. Warts (caused by papilloma virus) are the most familiar example and each is a clone derived from a single infected cell. The epithelim is the covering of internal and external surfaces of the body, including the lining of ves, A brain stem glioma that infiltrates diffusely throughout the pons (the middle portion of the brain stem), sometimes spreading to the midbrain (the upper portion of the brain stem) or he medulla (the bottom portion of the brain stem). The term diffuse int, A brain tumor caused by cancer elsewhere in the body spreading to the brain. Myelography, A device which radiates small areas of the brain. The x-knife can focus radiation therapy to a specific small area. Use of this type of radiation therapy allows a patient to receive radiation in smaller doses on repeated occasions and to be treated for tu, A doctor who specializes in diagnosing and treating brain tumors and other tumors of the nervous system.Neuropathologist, A doctor who specializes in surgery on the brain, spine, and other parts of the nervous system.Occipital brain tumor, A doctor who specializes in the diagnosis and treatment of disorders of the nervous system.Neuro-oncologist, A doctor who specializes in treating cancer. Some oncologists specialize in a particular type of cancer treatment. For example, a radiation oncologist specializes in treating cancer with radiation.Optic glioma, A doctor who specializes in using radiation to treat cancer.Radiation Therapy, A group of subcortical structures (as the hypothalamus, the hippocampus, and the amygdala) of the brain that are concerned especially with emotion and motivation.Lipoma brain tumor, A low-grade astrocytic tumor which may exhibit anaplastic features and generally carries a relatively favorable prognosis and should not be classified with other high-grade gliomas, such as anaplastic astrocytoma and glioblastoma multiforme.X-knife, A malignant tumor of the central nervous system and usually of a cerebral hemisphere -- called also glioblastoma.Steroids, A medical procedure for examining the spinal cord by means of X rays. It is especially useful in diagnosing spinal abscesses and tumors and dislocated intervertebral disks.Neurologist, A noninvasive imaging method that provides information about cellular activity (metabolic information). It is used along with magnetic resonance imaging (MRI) which provides information about the shape and size of the tumor (spatial information). Also cal, A painful benign tumor that develops by hypertrophy of a glomus -- called also glomangioma.High-grade, A pathologist who specializes in diseases of the nervous system. A pathologist identifies disease by studying cells and tissues under a microscope.Neurosurgeon, A procedure in which a small amount of radioactive glucose (sugar) is injected into a vein, and a scanner is used to make detailed, computerized pictures of areas inside the body where the glucose is used. Because cancer cells often use more glucose than, A procedure in which a thin needle called a spinal needle is put into the lower part of the spinal column to collect cerebrospinal fluid or to give drugs. Also called lumbar puncture.Spongioblastoma, A procedure in which a thin needle called a spinal needle is put into the lower part of the spinal column to collect cerebrospinal fluid or to give drugs. Also called spinal tap.Magnetic Resonance Angiogram (MRA), A slow-growing glioma of the optic nerve or optic chiasm heralded by visual loss, often with secondary strabismus followed by proptosis and loss of ocular movements.Papilloma, A small arteriovenous anastomosis together with its supporting structures: as a : a vascular tuft that suggests a renal glomerulus and that develops from the embryonic aorta in relation to the pronephros b : CAROTID BODY c : a tuft of the choroid plexus p, A special type of computed tomography (CT) scan in which a small amount of a radioactive drug is injected into a vein and a scanner is used to make detailed images of areas inside the body where the radioactive material is taken up by the cells. Single-ph, A term used to describe cells that look abnormal under a microscope. These cells are more likely to grow and spread quickly than cells in low-grade cancer or in growths that may become cancer.Hydrocephalus, A term used to describe cells that look nearly normal under a microscope. These cells are less likely to grow and spread more quickly than cells in high-grade cancer or in growths that may become cancer.Lumbar puncture, A tumor in the area of or relating to the occipital lobe. The occipital lobe is the posterior lobe of each cerebral hemisphere that is separated medially from the parietal lobe by the parieto-occipital sulcus, is indistinctly separated more laterally from, A tumor of meningioma type, of, relating to, or being in area of the sagittal suture of the skull. Also, see meningioma.Single-Photon Emission Computed Tomography (SPECT), A type of high-energy radiation. In low doses, x-rays are used to diagnose diseases by making pictures of the inside of the body. In high doses, x-rays are used to treat cancer., A type of radiation therapy that uses high-energy radiation from x-rays to kill cancer cells and shrink tumors.X-rays, Also called a mixed glioma, an astrocytoma with a high proportion of oligodendroglioma cells.Oligodendroglioma, An enlargement that resembles a tumor. It may result from inflammation, accumulation of fluid or other causes, and may or may not regress spontaneously.Pseudo tumor cerebri, An ependymoma in which there is a diffuse proliferation of subependymal fibrillary astrocytes among the ependymal tumor cells. A few are malignant and others cause obstructive hydrocephalus, but many are clinically silent and are discovered only at autops, Any of the largest group of primary tumors of the brain, composed of malignant glial cells. There are several different types. They can affect children too. Glomus tumor, Calcification. The process by which organic tissue becomes hardened by a deposit of calcium salts within its substance. Typical brain stem glioma, Delivers medication directly into the spinal fluid.Limbic system, Hydrocephalus. An abnormal increase in the amount of cerebrospinal fluid within the cranial cavity that is accompanied by expansion of the cerebral ventricles, enlargement of the skull and especially the forehead, and atrophy of the brain. Hypothalamic br, Hypothalamic hamartoma: A benign tumor of the hypothalamus, the area of the brain that controls body temperature, hunger, and thirst. (In technical terms, the hypothalamus lies beneath a structure known as the thalamus and forms the floor of the third ven, In IMRT, the beam intensity is varied across the treatment field. Rather than being treated with a single, large, uniform beam, the patient is treated instead with many very small beams; each can have a different intensity. By cross firing the tumor with, Intracranial pressure, headaches of varying intensity, and papilledema without any demonstrable intracranial lesion and that tends to occur in overweight women from 20 to 50 years of age -- called also benign intracranial hypertension.Radiation Oncologist, Lipomas are benign fatty growths that can be found virtually anywhere in the body. They generally do not change much in size over time. If they are not causing a problem they will usually be left alone. A lipoma specifically in the brain may or may not be, Malignant brain tumors do not have distinct borders and tend to grow rapidly, causing pressure within the brain. It is highly unlikely for malignant brain tumors to spread beyond the central nervous system.¥ Malignant tumors are more serious and often lif, MRA:The magnetic resonance angiogram, or MRA, is a noninvasive test that has demonstrated usefulness in defining the anatomy of blood vessels of certain size in the head and neck. MRA serves as a complement to traditional MRI scanning in evaluation of the, Of, relating to, or being the sagittal suture of the skull; or of, relating to, situated in, or being the median plane of the body or any plane parallel to it (a sagáitátal section dividing the body into unequal right and left parts).Sagittal meningioma, Of, relating to, or constituting the exceptionally hard and dense portion of the human temporal bone that contains the internal auditory (hearing) organs and is a pyramidal process wedged in at the base of the skull between the sphenoid and occipital bone, Oligodendroglioma. May be subdivided into primary brain tumors and the more common, secondary brain tumors. Primary brain tumors (for example astrocytoma, craniopharyngioma, glioma, ependymoma, neuroglioma, oligodendroglioma, glioblastoma multiforme, meni, Performed during surgery when a chemotherapy-soaked, biodegradable wafer is placed into the tumor resection cavity in a controlled-release fashion.Intraaterial chemotherapy, Pleomorphic", Radiation therapy (also called radiotherapy)uses high-energy radiation from x-rays, neutrons, and other sources to kill cancer cells and shrink tumors. It may come from a machine outside the body (external beam) or from materials that produce radiation th, Subarachnoid hemorrhage: Bleeding within the head into the space between two membranes that surround the brain. The bleeding is beneath the arachnoid membrane and just above the pia mater. (The arachnoid is the middle of three membranes around the brain w, Supporting tissue that is intermingled with the essential elements of nervous tissue especially in the brain, spinal cord, and ganglia, is of ectodermal origin, and is composed of a network of fine fibrils and of flattened stellate cells with numerous rad, Swelling is the enlargement of organs caused by accumulation of excess fluid in tissues, called edema. It can occur throughout the body (generalized), or a specific part or organ can be affected (localized). Swelling is considered one of the five characte, Synthetic anti-inflammatory compounds used to reduce the amount of swelling within brain, or other, tissue. Subarachnoid hemorrhage, The anterior part of the frontal lobe that is made up chiefly of association areas, mediates various inhibitory controls, and is bounded posteriorly by the ascending frontal convolution.Primary Brain Tumor, The lateral region of the cerebrum, below the lateral fissure. Within The temporal lobe of the brain is the center for smell, some association areas for memory and learning, and a region where choice is made of thoughts to express.Tumor, The medulloblastoma is highly malignant (grade IV) and usually originates in the cerebellum, the region of the brain that plays an important role in the integration of sensory perception, coordination and motor control. Also:¥ Type of primitive neuroectod, The most vital part of the entire brain, continuing as the bulbous portion of the spinal cord just above the foramen magnum and separated from the pons by a horizontal groove. It is one of three parts of the brainstem . The medulla contains the cardiac (h, The MRI, which uses magnetic fields, not X-rays, to provide detailed images, is more sensitive than the CT in detecting a brain tumor's presence. The MRI is a preferential imaging test because it outlines the normal brain structure in unique detail. The t, The original tumor of a cancer diagnosis. Cancer cells can invade and damage nearby tissues and organs. Also, cancer cells can break away from a malignant tumor and enter the bloodstream or the lymphatic system. This is how cancer spreads from the origina, The parietal lobes are found starting above the ear and spanning about three or four inches towards the back of the head on each side of the head. The parietal lobes can be divided into two functional regions. One involves sensation and perception and the, The tumor grows from the meninges, the layers of tissue covering the brain and spinal cord. As it grows, meningioma compresses other brain tissue which can affect cranial nerves. Sometimes the growth extends into facial bones, producing visible changes. I, The tumor, usually occurring in the cerebrum, forms from cells that create the fatty substance that covers and protects nerves. The cerebrum, which is located in the anterior or front portion of the brain, determines personality, intelligence, sensory imp, This is the most malignant form of astrocytoma, usually classified as Grade IV, one the most common primary tumors of the brain. It is a rapidly growing tumor. Glioma, Uses catheter tubes for high-dose delivery of chemotherapy in the brain's arteries.Intrathecal chemotherapy, Views capillaries feeding the tumor after highlighting them with a radioactive substance.Sagittal, WHO stands for World Health Organization, the entity which developed the widely used and accepted classification system for brain tumors. Brain tumors are graded from low grade (grade I) to high grade (grade IV). The grade of a tumor refers to the way the
GBM

A fast-growing type of central nervous system tumor that forms from glial (supportive) tissue of the brain and spinal cord and has cells that look very different from normal cells. GBM usually occurs in adults and affects the brain more often than the spinal cord. Also called glioblastoma, glioblastoma multiforme, and grade IV astrocytoma.

GCP

An international set of guidelines that helps make sure that the results of a clinical trial are reliable and that the patients are protected. GCP covers the way a clinical trial is designed, conducted, performed, monitored, audited, recorded, analyzed, and reported. Also called Good Clinical Practice.

Gene

The functional and physical unit of heredity passed from parent to offspring. Genes are pieces of DNA, and most genes contain the information for making a specific protein.

Gene Amplification

An increase in the number of copies of a gene. There may also be an increase in the RNA and protein made from that gene. Gene amplification is common in cancer cells, and some amplified genes may cause cancer cells to grow or become resistant to anticancer drugs. Genes may also be amplified in the laboratory for research purposes.

Gene Deletion

The loss of all or a part of a gene. There may also be a change in the RNA and protein made from that gene. Certain gene deletions are found in cancer and in other genetic diseases and abnormalities.

Gene Expression

The process by which a gene gets turned on in a cell to make RNA and proteins. Gene expression may be measured by looking at the RNA, or the protein made from the RNA, or what the protein does in a cell.

Gene Expression Profiling

A research method that measures messenger RNA made from many different genes in various cell types. It is being used as a diagnostic test to help identify subgroups of tumor types, to help predict which patients may respond to treatment, and which patients may be at increased risk for cancer relapse.

Gene Therapy

Treatment that alters a gene. In studies of gene therapy for cancer, researchers are trying to improve the body's natural ability to fight the disease or to make the cancer cells more sensitive to other kinds of therapy.

Gene Transfer

The insertion of genetic material into a cell.

Gene-modified

Cells that have been altered to contain different genetic material than they originally contained.

Generic

Official non-brand names by which medicines are known. Generic names usually refer to the chemical name of the drug.

Genetic

Inherited; having to do with information that is passed from parents to offspring through genes in sperm and egg cells.

Genetic Analysis

The study of a sample of DNA to look for mutations (changes) that may increase risk of disease or affect the way a person responds to treatment.

Genetic Marker

lteration in DNA that may indicate an increased risk of developing a specific disease or disorder.

Genetic Predisposition

An inherited increase in the risk of developing a disease. Also called genetic susceptibility.

Genetic Profile

Information about specific genes, including variations and gene expression, in an individual or in a certain type of tissue. A genetic profile may be used to help diagnose a disease or learn how the disease may progress or respond to treatment with drugs or radiation.

Genetic Susceptibility

An inherited increase in the risk of developing a disease. Also called genetic predisposition.

Genetic Testing

Analyzing DNA to look for a genetic alteration that may indicate an increased risk for developing a specific disease or disorder.

Genetics

The study of genes and heredity. Heredity is the passing of genetic information and traits (such as eye color and an increased chance of getting a certain disease) from parents to offspring.

Genomic Profile

Information about all the genes in an organism, including variations, gene expression, and the way those genes interact with each other and with the environment. A genomic profile may be used to discover why some people get certain diseases while other people do not, or why people respond differently to the same drug.

Genomics

The study of the complete genetic material, including genes and their functions, of an organism.

Glia

Supporting tissue that is intermingled with the essential elements of nervous tissue especially in the brain, spinal cord, and ganglia, is of ectodermal origin, and is composed of a network of fine fibrils and of flattened stellate cells with numerous radiating fibrillar processes.

Glial Cell

Any of the cells that hold nerve cells in place and help them work the way they should. The types of glial cells include oligodendrocytes, astrocytes, microglia, and ependymal cells. Also called neuroglia.

Glial Tumor

A general term for tumors of the central nervous system, including astrocytomas, ependymal tumors, glioblastoma multiforme, and primitive neuroectodermal tumors.

Glioblastoma

A fast-growing type of central nervous system tumor that forms from glial (supportive) tissue of the brain and spinal cord and has cells that look very different from normal cells. Glioblastoma usually occurs in adults and affects the brain more often than the spinal cord. Also called GBM, glioblastoma multiforme, and grade IV astrocytoma.

Glioblastoma multiforme

This is the most malignant form of astrocytoma, usually classified as Grade IV, one the most common primary tumors of the brain. It is a rapidly growing tumor.

Glioma

Any of the largest group of primary tumors of the brain, composed of malignant glial cells. There are several different types. They can affect children too.

Gliosarcoma

A type of glioma (cancer of the brain that comes from glial, or supportive, cells).

Glomus tumor

A painful benign tumor that develops by hypertrophy of a glomus -- called also glomangioma.

Growth Factor

A substance made by the body that functions to regulate cell division and cell survival. Some growth factors are also produced in the laboratory and used in biological therapy.