Key Points for This Section

An adult brain tumor is a disease in which abnormal cells form in the tissues of the brain. A brain tumor that starts in another part of the body and spreads to the brain is called a metastatic tumor. The brain controls many important body functions. The spinal cord connects the brain to nerves in most parts of the body. There are different types of brain and spinal cord tumors. Astrocytic Tumors Oligodendroglial Tumors Mixed Gliomas Ependymal Tumors Embryonal Cell Tumors: Medulloblastoma (Grade IV) Pineal Parenchymal Tumors Meningeal Tumors Germ Cell Tumors Tumors of the Sellar Region: Craniopharyngioma (Grade I) and Pituitary Tumor Other Adult Brain Tumors Recurrent Brain Tumors The cause of most adult brain tumors is unknown. The symptoms of adult brain and spinal cord tumors are not the same in every person. Tests that examine the brain and spinal cord are used to detect (find) adult brain tumors. Most adult brain tumors are diagnosed and removed in surgery. Certain factors affect prognosis (chance of recovery) and treatment options.

An adult brain tumor is a disease in which abnormal cells form in the tissues of the brain.

There are many types of brain and spinal cord tumors. The tumors are formed by the abnormal growth of cells and may begin in different parts of the brain or spinal cord. Together, the brain and spinal cord make up the central nervous system (CNS).

The tumors may be benign (not cancer) or malignant (cancer). Benign brain tumors grow and press on nearby areas of the brain. They rarely spread into other tissues and may recur (come back). Malignant brain tumors are likely to grow quickly and spread into other brain tissue. When a tumor grows into or presses on an area of the brain, it may keep that part of the brain from working the way it should. Both benign and malignant brain tumors can cause symptoms and, sometimes, death.

Brain tumors can occur in both adults and children. However, treatment for children may be different than treatment for adults. (See the PDQ summary on Childhood Brain and Spinal Cord Tumors Treatment Overview ¹ for more information on the treatment of children.)

For information about lymphoma that begins in the brain, see the PDQ summary on Primary CNS Lymphoma Treatment ².

A brain tumor that starts in another part of the body and spreads to the brain is called a metastatic tumor.

Tumors that start in the brain are called primary brain tumors. Often, tumors found in the brain have started somewhere else in the body and spread to one or more parts of the brain. These are called metastatic brain tumors (or brain metastases). Metastatic brain tumors are more common than primary brain tumors.

The types of cancer that commonly spread to the brain are melanoma and cancer of the breast, colon, lung, and unknown primary site. The types of cancer that commonly spread to the spinal cord are lymphoma and cancer of the lung, breast, and prostate. About half of metastatic brain and spinal cord tumors are caused by lung cancer. Leukemia, lymphoma, breast cancer, and gastrointestinal cancer may spread to the leptomeninges (the two innermost membranes covering the brain and spinal cord).

See the following PDQ summaries for more information on cancers that commonly spread to the brain and spinal cord:

• Adult Hodgkin Lymphoma Treatment ³
• Adult Non-Hodgkin Lymphoma Treatment ⁴
• Breast Cancer Treatment ⁵
• Carcinoma of Unknown Primary Treatment ⁶
• Colon Cancer Treatment ⁷
• Melanoma Treatment ⁸
• Non-Small Cell Lung Cancer Treatment ⁹
• Small Cell Lung Cancer Treatment ¹⁰

The brain controls many important body functions.

The brain has three major parts:

• The cerebrum is the largest part of the brain. It is at the top of the head. The cerebrum controls thinking, learning, problem solving, emotions, speech, reading, writing, and voluntary movement.
• The cerebellum is in the lower back of the brain (near the middle of the back of the head). It controls movement, balance, and posture.
• The brain stem connects the brain to the spinal cord. It is in the lowest part of the brain (just above the back of the neck). The brain stem controls breathing, heart rate, and the nerves and muscles used in seeing, hearing, walking, talking, and eating.

The spinal cord connects the brain to nerves in most parts of the body.

The spinal cord is a column of nerve tissue that runs from the brain stem down the center of the back. It is covered by three thin layers of tissue called membranes. These membranes are surrounded by the vertebrae (back bones). Spinal cord nerves carry messages between the brain and the rest of the body, such as a signal from the brain to cause muscles to move or from the skin to the brain about the sense of touch.

There are different types of brain and spinal cord tumors.

Brain and spinal cord tumors are named based on the type of cell they formed in and where the tumor first formed in the CNS. The grade of a tumor may be used to tell the difference between slow- and fast-growing types of the tumor. The grade of a tumor is based on how abnormal the cancer cells look under a microscope and how quickly the tumor is likely to grow and spread.

Tumor Grading System

• Grade I (low-grade) — The tumor grows slowly, has cells that look a lot like normal cells, and rarely spreads into nearby tissues. It may be possible to remove the entire tumor by surgery.
• Grade II — The tumor grows slowly, but may spread into nearby tissue and may recur (come back). Some tumors may become a higher-grade tumor.
• Grade III — The tumor grows quickly, is likely to spread into nearby tissue, and the tumor cells look very different from normal cells.
• Grade IV (high-grade) — The tumor grows and spreads very quickly and the cells do not look like normal cells. There may be areas of dead cells in the tumor. Grade IV brain tumors are harder to cure than lower-grade tumors.

Astrocytic Tumors

An astrocytic tumor begins in star-shaped brain cells called astrocytes, which help keep nerve cells healthy. An astrocyte is a type of glial cell and is sometimes called a glioma. Astrocytic tumors include the following:

• Brain stem glioma: A brain stem glioma forms in the brain stem, which is the part of the brain connected to the spinal cord. It is often a high-grade tumor, which spreads widely through the brain stem and is hard to cure. A brain stem glioma rarely occurs in adults. (See the PDQ summary on Childhood Brain Stem Glioma Treatment ¹¹ for more information.)
• Pineal astrocytic tumor: A pineal astrocytic tumor forms in tissue around the pineal gland and may be any grade. The pineal gland is a tiny organ in the brain that makes melatonin, a hormone that helps control the sleeping and waking cycle.
• Pilocytic astrocytoma (grade I): A pilocytic astrocytoma grows slowly in the brain or spinal cord. It may be in the form of a cyst and rarely spreads into nearby tissues. This type of tumor is most common in children and young adults and in people with neurofibromatosis type 1 (NF1). A pilocytic astrocytoma rarely causes death.
• Diffuse astrocytoma (grade II): A diffuse astrocytoma grows slowly, but often spreads into nearby tissues. Sometimes a diffuse astrocytoma progresses to a higher grade and becomes an anaplastic astrocytoma or a glioblastoma. A diffuse astrocytoma can form in any part of the brain but most often forms in the cerebrum. It is most common in young adults and in people with Li-Fraumeni syndrome. It is also called a low-grade diffuse astrocytoma.
• Anaplastic astrocytoma (grade III): An anaplastic astrocytoma grows quickly and spreads into nearby tissues. An anaplastic astrocytoma may progress to a higher grade and become a glioblastoma. An anaplastic astrocytoma forms most often in the cerebrum and is most common in adults. An anaplastic astrocytoma is also called a malignant astrocytoma or high-grade astrocytoma.
• Glioblastoma (grade IV): A glioblastoma grows and spreads very quickly. A glioblastoma forms most often in the cerebrum. This type of tumor is most common in adults. This type of tumor has a poor prognosis. It is also called glioblastoma multiforme.

Oligodendroglial Tumors

An oligodendroglial tumor begins in brain cells called oligodendrocytes, which help keep nerve cells healthy. Oligodendrocytes are a type of glial cell and are sometimes called a glioma. Grades of oligodendroglial tumors include the following:

• Oligodendroglioma (grade II): An oligodendroglioma grows and spreads slowly and the tumor cells look very much like normal cells. This type of tumor most often forms in the cerebrum. An oligodendroglioma is most common in adults.
• Anaplastic oligodendroglioma (grade III): An anaplastic oligodendroglioma grows quickly and the tumor cells look very different from normal cells. It may grow in one place or in many places throughout the brain. This type of cancer most often forms in the cerebrum.

Mixed Gliomas

A mixed glioma is a brain tumor that has two types of tumor cells in it — oligodendrocytes and astrocytes. This type of tumor most often forms in the cerebrum.

• Oligoastrocytoma (grade II): An oligoastrocytoma is a slow-growing tumor and the tumor cells don't look very different from normal cells.
• Anaplastic oligoastrocytoma (grade III): The tumor cells in an anaplastic oligoastrocytoma look very different from normal cells.

Ependymal Tumors

An ependymal tumor usually begins in cells that line the fluid -filled spaces in the brain and around the spinal cord. Ependymal cells are a type of glial cell and are sometimes called a glioma. Grades of ependymal tumors include the following:

• Ependymoma (grade I or II): A grade I or II ependymoma grows slowly and has cells that look very much like normal cells. There are two types of grade I ependymoma — myxopapillary ependymoma and subependymoma. These tumors are most common in adults. A grade II ependymoma grows in the ventricle and its connecting paths or in the spinal cord. It is most common in children and young adults and in people with neurofibromatosis type 2 (NF2). (See the PDQ summary on Childhood Ependymoma Treatment ¹² for more information.)
• Anaplastic ependymoma (grade III): An anaplastic ependymoma grows very quickly and has a poor prognosis.

Embryonal Cell Tumors: Medulloblastoma (Grade IV)

A medulloblastoma is a type of embryonal tumor. The tumor forms in brain cells when the fetus is beginning to develop. This type of brain tumor often begins in the cerebellum. The tumor may spread from the brain to the spine through the cerebrospinal fluid (CSF). A medulloblastoma occurs most often in children or young adults and in people with Turcot syndrome type 2 or nevoid basal cell carcinoma syndrome.

See the following PDQ summaries for more information on embryonal tumors in children:

• Childhood Central Nervous System Embryonal Tumors Treatment ¹³
• Childhood Central Nervous System Atypical Teratoid/Rhabdoid Tumor Treatment ¹⁴

Pineal Parenchymal Tumors

A pineal parenchymal tumor forms in parenchymal cells or pineocytes, which are the cells that make up most of the pineal gland. These tumors are different from pineal astrocytic tumors. Grades of pineal parenchymal tumors include the following:

• Pineocytomas (grade II): A pineocytoma is a slow-growing pineal tumor that occurs most often in adults.
• Pineoblastomas (grade IV): A pineoblastoma is a rare tumor that is very likely to spread. This type of tumor is most common in children. (See the PDQ summary on Childhood Central Nervous System Embryonal Tumors Treatment ¹³ for more information.)

Meningeal Tumors

A meningeal tumor, also called a meningioma, forms in the meninges (thin layers of tissue that cover the brain and spinal cord). It can form from different types of brain or spinal cord cells. A meningioma is most common in adults. Types of meningeal tumors include the following:

• Meningioma (grade I): A grade I meningioma is the most common type of meningeal tumor. A grade I meningioma is a slow-growing, benign tumor that forms most often in the dura mater (the layer of tissue that covers the brain and is closest to the skull). It is most common in women.
• Meningioma (grade II and III): This is a rare, malignant meningeal tumor. It grows quickly and is likely to spread within the brain and spinal cord. A grade III meningioma is most common in men.

A hemangiopericytoma is not a meningeal tumor but is treated like a grade II or III meningioma. A hemangiopericytoma usually forms in the dura mater. It often recurs (comes back) after treatment and usually spreads to other parts of the body.

Germ Cell Tumors

A germ cell tumor forms in germ cells, which are the cells that develop into sperm in men or ova (eggs) in women. Germ cell tumors usually form in the center of the brain, near the pineal gland. Germ cell tumors can spread to other parts of the brain and spinal cord. There are different types of germ cell tumors. These include germinomas, teratomas, embryonal yolk sac carcinomas, and choriocarcinomas. Germ cell tumors can be either benign or malignant.

Most germ cell tumors occur in children and in people with Klinefelter syndrome. (See the PDQ summary on Childhood Brain and Spinal Cord Tumors Treatment Overview ¹ for more information.)

Tumors of the Sellar Region: Craniopharyngioma (Grade I) and Pituitary Tumor

A tumor of the sellar region begins in the center of the brain, just above the back of the nose. It can form from different types of brain or spinal cord cells.

• Craniopharyngioma (grade I): A craniopharyngioma is a rare tumor that usually forms just above the pituitary gland (a pea-sized organ at the bottom of the brain that controls other glands). The tumor may grow into nearby tissues, including the pituitary gland and optic nerves. This can affect many functions, including hormone-making and vision. These tumors occur in adults and children. (See the PDQ summary on Childhood Craniopharyngioma Treatment ¹⁵ for more information on the treatment of children.)
• Pituitary tumor: See the PDQ summary on Pituitary Tumors Treatment ¹⁶ for more information.

Other Adult Brain Tumors

There are many other types of adult brain tumors that are rare and are not discussed in this summary. See the PDQ health professional summary on Adult Brain Tumors Treatment ¹⁷ for information about these other types of adult brain tumors:

• Pleomorphic xanthoastrocytoma ¹⁸
• Subependymal giant cell astrocytoma ¹⁹
• Astroblastoma ²⁰
• Chordoid glioma of the third ventricle ²¹
• Gliomatosis cerebri ²²
• Gangliocytoma or ganglioglioma ²³
• Desmoplastic infantile astrocytoma or ganglioglioma ²⁴
• Dysembryoplastic neuroepithelial tumor ²⁵
• Central neurocytoma ²⁶
• Cerebellar liponeurocytoma ²⁷
• Paraganglioma ²⁸
• Ependymoblastoma ²⁹
• Supratentorial primitive neuroectodermal tumor (PNET) ³⁰
• Choroid plexus papilloma or carcinoma ³¹
• Pineal parenchymal tumors of intermediate differentiation ³²
• Melanocytic lesions ³³
• Capillary hemangioblastoma ³⁴
• Schwannoma ³⁵

Recurrent Brain Tumors

A recurrent brain tumor is a tumor that has recurred (come back) after it has been treated. Brain tumors often recur, sometimes many years after the first tumor. The tumor may recur at the same place in the brain or in other parts of the central nervous system.

The cause of most adult brain tumors is unknown.

Anything that increases your chance of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn’t mean that you will not get cancer. People who think they may be at risk should discuss this with their doctor. There are few known risk factors for brain tumors. The following conditions may increase the risk of developing certain types of brain tumors:

• Being exposed to vinyl chloride may increase the risk of glioma.
• Past treatment with radiation therapy to the scalp or brain may increase the risk of meningioma.
• Infection with the Epstein-Barr virus, having AIDS (acquired immunodeficiency syndrome), or receiving an organ transplant may increase the risk of primary CNS lymphoma. (See the PDQ summary on Primary CNS Lymphoma ² for more information.)
• Having certain genetic syndromes may increase the risk of developing the following types of brain tumors:
  • Neurofibromatosis type 1 or 2.
  • von Hippel-Lindau disease.
  • Tuberous sclerosis.
  • Li-Fraumeni syndrome.
  • Turcot syndrome type 1 and type 2.
  • Klinefelter syndrome.
  • Nevoid basal cell carcinoma syndrome.

The symptoms of adult brain and spinal cord tumors are not the same in every person.

The symptoms caused by a brain tumor depend on where the tumor formed in the brain, the functions controlled by that part of the brain, and the size of the tumor. Headaches and other symptoms may be caused by adult brain tumors. Other conditions may cause the same symptoms. A doctor should be consulted if any of the following problems occur:

Brain Tumors

• Morning headache or headache that goes away after vomiting.
• Frequent nausea and vomiting.
• Vision, hearing, and speech problems.
• Loss of balance and trouble walking.
• Weakness on one side of the body.
• Unusual sleepiness or change in activity level.
• Unusual changes in personality or behavior.
• Seizures.

Spinal Cord Tumors

• Back pain or pain that spreads from the back towards the arms or legs.
• A change in bowel habits or trouble urinating.
• Weakness in the legs.
• Trouble walking.

Tests that examine the brain and spinal cord are used to detect (find) adult brain tumors.

The following tests and procedures may be used:

• Physical exam and history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.
• Neurological exam: A series of questions and tests to check the brain, spinal cord, and nerve function. The exam checks a person’s mental status, coordination, and ability to walk normally, and how well the muscles, senses, and reflexes work. This may also be called a neuro exam or a neurologic exam.
• Visual field exam: An exam to check a person’s field of vision (the total area in which objects can be seen). This test measures both central vision (how much a person can see when looking straight ahead) and peripheral vision (how much a person can see in all other directions while staring straight ahead). Any loss of vision may be a sign of a tumor that has damaged or pressed on the parts of the brain that affect eyesight.
• Tumor marker test: A procedure in which a blood, urine, or tissue sample is examined to measure the amounts of certain substances released into the blood by organs, tissues, or tumor cells in the body. Certain substances are linked to specific types of cancer when found in increased levels in the body. These are called tumor markers.
• Gene testing: A laboratory test in which a sample of blood or tissue is tested for changes in a chromosome that has been linked with a certain type of brain tumor.
• Lumbar puncture: A procedure used to collect cerebrospinal fluid from the spinal column. This is done by placing a needle into the spinal column. The cerebrospinal fluid is viewed under a microscope by a pathologist to check for signs of cancer. This procedure is also called an LP or spinal tap.
• CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
• MRI (magnetic resonance imaging) with gadolinium: A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of the brain and spinal cord. A substance called gadolinium is injected into a vein. The gadolinium collects around the cancer cells so they show up brighter in the picture. This procedure is also called nuclear magnetic resonance imaging (NMRI). Sometimes a procedure called magnetic resonance spectroscopy (MRS) is done during the MRI scan. An MRS is used to diagnose tumors, based on their chemical make-up.
• SPECT scan (single photon emission computed tomography scan): A procedure that uses a special camera linked to a computer to make a 3-dimensional (3-D) picture of the brain. A small amount of a radioactive substance is injected into a vein or inhaled through the nose. As the substance travels through the blood, the camera rotates around the head and takes pictures of the brain. There will be increased blood flow and more chemical reactions (metabolism) in areas where cancer cells are growing. These areas will show up brighter in the picture. This procedure may be done just before or after a CT scan.
• PET scan (positron emission tomography scan): A procedure to find malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the brain. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than normal cells do.
• Angiogram: A procedure to look at blood vessels and the flow of blood in the brain. A contrast dye is injected into the blood vessel. As the contrast dye moves through the blood vessel, x-rays are taken to see if there are any blockages.

Most adult brain tumors are diagnosed and removed in surgery.

If doctors think there may be a brain tumor, a biopsy may be done to remove a sample of tissue. For tumors in the brain, the biopsy is done by removing part of the skull and using a needle to remove the tissue sample. A pathologist views the tissue under a microscope to look for cancer cells. If cancer cells are found, the doctor may remove as much tumor as safely possible during the same surgery. After the surgery, a pathologist checks the cancer cells to find out the type and grade of brain tumor. The grade of the tumor is based on how abnormal the cancer cells look under a microscope and how quickly the tumor is likely to grow and spread. A CT scan or MRI may be used to find out if any cancer cells remain after surgery.

The following tests may be done on the tumor tissue that is removed:

• Immunohistochemistry study: A laboratory test in which a substance such as an antibody, dye, or radioisotope is added to a sample of cancer tissue to test for certain antigens. This type of study is used to tell the difference between different types of cancer.
• Light and electron microscopy: A laboratory test in which cells in a sample of tissue are viewed under regular and high-powered microscopes to look for certain changes in the cells.
• Cytogenetic analysis: A laboratory test in which cells in a sample of tissue are viewed under a microscope to look for certain changes in the chromosomes.

Sometimes a biopsy or surgery cannot be done safely because of where the tumor formed in the brain or spinal cord. These tumors are diagnosed based on the results of imaging tests and other procedures.

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis (chance of recovery) and treatment options for primary brain tumors depend on the following:

• The type and grade of the tumor.
• Where the tumor is in the brain.
• Whether the tumor can be removed by surgery.
• Whether cancer cells remain after surgery.
• Whether there are certain changes in the chromosomes.
• Whether the cancer has just been diagnosed or has recurred (come back).
• The patient's general health.

The prognosis and treatment options for metastatic brain tumors depend on the following:

• Whether the patient is younger than 60 years.
• Whether there are more than two tumors in the brain or spinal cord.
• Where in the brain or spinal cord the tumors are.
• How well the tumor responds to treatment.
• Whether the primary tumor continues to grow or spread.

The prognosis is better for brain metastases from breast cancer than from other types of primary cancer. The prognosis is worse for brain metastases from colon cancer.

Glossary Terms

A graphic display of depth, width, and height. Also called 3-D.

Not normal. An abnormal lesion or growth may be cancer, premalignant (likely to become cancer), or benign (not cancer).

A disease caused by the human immunodeficiency virus (HIV). People with AIDS are at an increased risk for developing certain cancers and for infections that usually occur only in individuals with a weak immune system. Also called acquired immunodeficiency syndrome.

A term used to describe cancer cells that divide rapidly and have little or no resemblance to normal cells.

An x-ray of blood vessels. The person receives an injection of dye to outline the vessels on the x-ray.

A type of protein made by plasma cells (a type of white blood cell) in response to an antigen (foreign substance). Each antibody can bind to only one specific antigen. The purpose of this binding is to help destroy the antigen. Antibodies can work in several ways, depending on the nature of the antigen. Some antibodies destroy antigens directly. Others make it easier for white blood cells to destroy the antigen.

A substance that causes the immune system to make a specific immune response.

A large, star-shaped cell that holds nerve cells in place and helps them develop and work the way they should. An astrocyte is a type of glial cell.

A tumor that begins in the brain or spinal cord in small, star-shaped cells called astrocytes.

Not cancer. Benign tumors may grow larger but do not spread to other parts of the body.

A noncancerous growth that does not invade nearby tissue or spread to other parts of the body.

The removal of cells or tissues for examination by a pathologist. The pathologist may study the tissue under a microscope or perform other tests on the cells or tissue. There are many different types of biopsy procedures. The most common types include: (1) incisional biopsy, in which only a sample of tissue is removed; (2) excisional biopsy, in which an entire lump or suspicious area is removed; and (3) needle biopsy, in which a sample of tissue or fluid is removed with a needle. When a wide needle is used, the procedure is called a core biopsy. When a thin needle is used, the procedure is called a fine-needle aspiration biopsy.

A tissue with red blood cells, white blood cells, platelets, and other substances suspended in fluid called plasma. Blood takes oxygen and nutrients to the tissues, and carries away wastes.

A tube through which the blood circulates in the body. Blood vessels include a network of arteries, arterioles, capillaries, venules, and veins.

The long, tube-shaped organ in the abdomen that completes the process of digestion. The bowel has two parts, the small bowel and the large bowel. Also called intestine.

Cancer that has spread from the original (primary) tumor to the brain.

The part of the brain that is connected to the spinal cord.

A tumor located in the part of the brain that connects to the spinal cord (the brain stem). It may grow rapidly or slowly, depending on the grade of the tumor.

The growth of abnormal cells in the tissues of the brain. Brain tumors can be benign (not cancer) or malignant (cancer).

Glandular organ located on the chest. The breast is made up of connective tissue, fat, and breast tissue that contains the glands that can make milk. Also called mammary gland.

Cancer that forms in tissues of the breast, usually the ducts (tubes that carry milk to the nipple) and lobules (glands that make milk). It occurs in both men and women, although male breast cancer is rare.

A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

Cancer that begins in the skin or in tissues that line or cover internal organs.

The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.

The brain and spinal cord. Also called CNS.

The portion of the brain in the back of the head between the cerebrum and the brain stem. The cerebellum controls balance for walking and standing, and other complex motor functions.

The fluid that flows in and around the hollow spaces of the brain and spinal cord, and between two of the meninges (the thin layers of tissue that cover and protect the brain and spinal cord). Cerebrospinal fluid is made by tissue called the choroid plexus in the ventricles (hollow spaces) in the brain. Also called CSF.

The largest part of the brain. It is divided into two hemispheres, or halves, called the cerebral hemispheres. Areas within the cerebrum control muscle functions and also control speech, thought, emotions, reading, writing, and learning.

A malignant, fast-growing tumor that develops from trophoblastic cells (cells that help an embryo attach to the uterus and help form the placenta). Almost all choriocarcinomas form in the uterus after fertilization of an egg by a sperm, but a small number form in a testis or an ovary. Choriocarcinomas spread through the blood to other organs, especially the lungs. They are a type of gestational trophoblastic disease. Also called chorioblastoma, chorioepithelioma, and chorionic carcinoma.

Part of a cell that contains genetic information. Except for sperm and eggs, all human cells contain 46 chromosomes.

The brain and spinal cord. Also called central nervous system.

The longest part of the large intestine, which is a tube-like organ connected to the small intestine at one end and the anus at the other. The colon removes water and some nutrients and electrolytes from partially digested food. The remaining material, solid waste called stool, moves through the colon to the rectum and leaves the body through the anus.

Cancer that forms in the tissues of the colon (the longest part of the large intestine). Most colon cancers are adenocarcinomas (cancers that begin in cells that make and release mucus and other fluids).

A dye or other substance that helps show abnormal areas inside the body. It is given by injection into a vein, by enema, or by mouth. Contrast material may be used with x-rays, CT scans, MRI, or other imaging tests.

A benign brain tumor that may be considered malignant because it can damage the hypothalamus, the area of the brain that controls body temperature, hunger, and thirst.

A series of detailed pictures of areas inside the body taken from different angles. The pictures are created by a computer linked to an x-ray machine. Also called CAT scan, computed tomography scan, computerized axial tomography scan, and computerized tomography.

To heal or restore health; a treatment to restore health.

A sac or capsule in the body. It may be filled with fluid or other material.

The study of chromosomes and chromosomal abnormalities.

The process of identifying a disease, such as cancer, from its signs and symptoms.

Widely spread; not localized or confined.

A microscope (device used to magnify small objects) that uses electrons (instead of light) to produce an enlarged image. An electron microscope shows tiny details better than any other type of microscope.

A mass of rapidly growing cells that begins in embryonic (fetal) tissue. Embryonal tumors may be benign or malignant, and include neuroblastomas and Wilms tumors. Also called embryoma.

A type of brain tumor that begins in cells lining the spinal cord central canal (fluid-filled space down the center) or the ventricles (fluid-filled spaces of the brain). Ependymal tumors may also form in the choroid plexus (tissue in the ventricles that makes cerebrospinal fluid). Also called ependymoma.

A type of brain tumor that begins in cells lining the spinal cord central canal (fluid-filled space down the center) or the ventricles (fluid-filled spaces of the brain). Ependymomas may also form in the choroid plexus (tissue in the ventricles that makes cerebrospinal fluid). Also called ependymal tumor.

A common virus that remains dormant in most people. It causes infectious mononucleosis and has been associated with certain cancers, including Burkitt lymphoma, immunoblastic lymphoma, and nasopharyngeal carcinoma. Also called EBV.

The developing offspring from 7 to 8 weeks after conception until birth.

A substance that flows smoothly and takes the shape of its container. Liquids and gases are fluids.

A metal element that is used in magnetic resonance imaging (MRI) and other imaging methods. It is a contrast agent, which helps show abnormal tissue in the body during imaging with a special machine.

Refers to the stomach and intestines. Also called GI.

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

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

A reproductive cell of the body. Germ cells are egg cells in females and sperm cells in males.

A type of tumor that begins in the cells that give rise to sperm or eggs. Germ cell tumors can occur almost anywhere in the body and can be either benign or malignant.

The most common type of germ cell tumor in the brain.

An organ that makes one or more substances, such as hormones, digestive juices, sweat, tears, saliva, or milk. Endocrine glands release the substances directly into the bloodstream. Exocrine glands release the substances into a duct or opening to the inside or outside of the body.

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.

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.

A cancer of the brain that begins in glial cells (cells that surround and support nerve cells).

A type of sugar; the chief source of energy for living organisms.

The grade of a tumor depends on how abnormal the cancer cells look under a microscope and how quickly the tumor is likely to grow and spread. Grading systems are different for each type of cancer.

A type of cancer involving blood vessels and soft tissue.

When referring to cancerous and precancerous growths, 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 cancerous and precancerous growths.

One of many chemicals made by glands in the body. Hormones circulate in the bloodstream and control the actions of certain cells or organs. Some hormones can also be made in the laboratory.

In medicine, a process that makes pictures of areas inside the body. Imaging uses methods such as x-rays (high-energy radiation), ultrasound (high-energy sound waves), and radio waves.

Invasion and multiplication of germs in the body. Infections can occur in any part of the body and can spread throughout the body. The germs may be bacteria, viruses, yeast, or fungi. They can cause a fever and other problems, depending on where the infection occurs. When the body’s natural defense system is strong, it can often fight the germs and prevent infection. Some cancer treatments can weaken the natural defense system.

In medicine, refers to the act of taking a substance into the body by breathing.

Use of a syringe and needle to push fluids or drugs into the body; often called a "shot."

A genetic disorder in males caused by having one or more extra X chromosomes. Males with this disorder may have larger than normal breasts, a lack of facial and body hair, a rounded body type, and small testicles. They may learn to speak much later than other children and may have difficulty learning to read and write. Klinefelter syndrome increases the risk of developing extragonadal germ cell tumors and breast cancer.

A medical procedure that involves testing a sample of blood, urine, or other substance from the body. Tests can help determine a diagnosis, plan treatment, check to see if treatment is working, or monitor the disease over time.

Cancer that starts in blood-forming tissue such as the bone marrow and causes large numbers of blood cells to be produced and enter the bloodstream.

A rare, inherited predisposition to multiple cancers, caused by an alteration in the p53 tumor suppressor gene.

When referring to cancerous and precancerous growths, a term used to describe cells that look nearly normal under a microscope. These cells are less likely to grow and spread quickly than cells in high-grade cancerous or precancerous growths.

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.

One of a pair of organs in the chest that supplies the body with oxygen, and removes carbon dioxide from the body.

Cancer that forms in tissues of the lung, usually in the cells lining air passages. The two main types are small cell lung cancer and non-small cell lung cancer. These types are diagnosed based on how the cells look under a microscope.

Cancer that begins in cells of the immune system. There are two basic categories of lymphomas. One kind is Hodgkin lymphoma, which is marked by the presence of a type of cell called the Reed-Sternberg cell. The other category is non-Hodgkin lymphomas, which includes a large, diverse group of cancers of immune system cells. Non-Hodgkin lymphomas can be further divided into cancers that have an indolent (slow-growing) course and those that have an aggressive (fast-growing) course. These subtypes behave and respond to treatment differently. Both Hodgkin and non-Hodgkin lymphomas can occur in children and adults, and prognosis and treatment depend on the stage and the type of cancer.

Cancerous. Malignant tumors can invade and destroy nearby tissue and spread to other parts of the body.

A malignant brain tumor that begins in the lower part of the brain and that can spread to the spine or to other parts of the body. Medulloblastomas are a type of primitive neuroectodermal tumor (PNET).

A form of cancer that begins in melanocytes (cells that make the pigment melanin). It may begin in a mole (skin melanoma), but can also begin in other pigmented tissues, such as in the eye or in the intestines.

A hormone made by the pineal gland (tiny organ near the center of the brain). Melatonin helps control the body’s sleep cycle, and is an antioxidant. It is also made in the laboratory and sold as a supplement.

A very thin layer of tissue that covers a surface.

Having to do with the meninges (three thin layers of tissue that cover and protect the brain and spinal cord).

The three thin layers of tissue that cover and protect the brain and spinal cord.

A type of slow-growing tumor that forms in the meninges (thin layers of tissue that cover and protect the brain and spinal cord). Meningiomas usually occur in adults.

The total of all chemical changes that take place in a cell or an organism. These changes make energy and the materials needed for growth, reproduction, and maintaining health. They also help get rid of toxic substances.

Having to do with metastasis, which is the spread of cancer from one part of the body to another.

A brain tumor that forms from more than one type of brain cell, usually astrocytes and oligodendrocytes.

A procedure in which radio waves and a powerful magnet linked to a computer are used to create detailed pictures of areas inside the body. These pictures can show the difference between normal and diseased tissue. MRI makes better images of organs and soft tissue than other scanning techniques, such as computed tomography (CT) or x-ray. MRI is especially useful for imaging the brain, the spine, the soft tissue of joints, and the inside of bones. Also called magnetic resonance imaging, NMRI, and nuclear magnetic resonance imaging.

A feeling of sickness or discomfort in the stomach that may come with an urge to vomit. Nausea is a side effect of some types of cancer therapy.

A bundle of fibers that receives and sends messages between the body and the brain. The messages are sent by chemical and electrical changes in the cells that make up the nerves.

A type of cell that receives and sends messages from the body to the brain and back to the body. The messages are sent by a weak electrical current. Also called neuron.

A rare genetic condition that causes brown spots and tumors on the skin, freckling in skin areas not exposed to the sun, tumors on the nerves, and developmental changes in the nervous system, muscles, bone, and skin. Also called NF1.

A genetic condition in which tumors form on the nerves of the inner ear and cause loss of hearing and balance. Tumors may also occur in the brain and on nerves in the skull and spinal cord, and may cause loss of speech, eye movement, and the ability to swallow. Also called acoustic neurofibromatosis and NF2.

A series of questions and tests to check brain, spinal cord, and nerve function. The exam checks a person’s mental status, coordination, ability to walk, and how well the muscles, sensory systems, and deep tendon reflexes work.

A genetic condition that causes unusual facial features and disorders of the skin, bones, nervous system, eyes, and endocrine glands. People with this syndrome have a higher risk of basal cell carcinoma. Also called basal cell nevus syndrome and Gorlin syndrome.

A brain tumor that forms from both oligodendrocytes and astrocytes, which are types of glial cells (cells that cover and protect nerve cells in the brain and spinal cord and help them work the way they should). An oligoastrocytoma is a type of mixed glioma.

A cell that forms the myelin sheath (a layer that covers and protects nerve cells) in the brain and spinal cord. An oligodendrocyte is a type of glial cell.

A rare, slow-growing tumor that begins in oligodendrocytes (cells that cover and protect nerve cells in the brain and spinal cord). Also called oligodendroglioma.

A rare, slow-growing tumor that begins in oligodendrocytes (cells that cover and protect nerve cells in the brain and spinal cord). Also called oligodendroglial tumor.

The nerve that carries messages from the retina to the brain.

A part of the body that performs a specific function. For example, the heart is an organ.

The essential or functional elements of an organ.

A doctor who identifies diseases by studying cells and tissues under a microscope.

PDQ is an online database developed and maintained by the National Cancer Institute. Designed to make the most current, credible, and accurate cancer information available to health professionals and the public, PDQ contains peer-reviewed summaries on cancer treatment, screening, prevention, genetics, complementary and alternative medicine, and supportive care; a registry of cancer clinical trials from around the world; and directories of physicians, professionals who provide genetics services, and organizations that provide cancer care. Most of this information, and more specific information about PDQ, can be found on the NCI's Web site at http://www.cancer.gov/cancertopics/pdq. Also called Physician Data Query.

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 normal cells, the pictures can be used to find cancer cells in the body. Also called positron emission tomography scan.

An exam of the body to check for general signs of disease.

Made up of cells that look like fibers when viewed under a microscope.

A tiny organ in the cerebrum that produces melatonin. Also called pineal body and pineal organ.

A fast growing type of brain tumor that occurs in or around the pineal gland, a tiny organ near the center of the brain.

A slow growing type of brain tumor that occurs in or around the pineal gland, a tiny organ near the center of the brain.

The main endocrine gland. It produces hormones that control other glands and many body functions, especially growth.

Cancer that forms in the lymph tissue of the brain, spinal cord, meninges (outer covering of the brain), or eye (called ocular lymphoma). Also called PCNSL and primary central nervous system lymphoma.

The original tumor.

The likely outcome or course of a disease; the chance of recovery or recurrence.

In medicine, the course of a disease, such as cancer, as it becomes worse or spreads in the body.

A gland in the male reproductive system. The prostate surrounds the part of the urethra (the tube that empties the bladder) just below the bladder, and produces a fluid that forms part of the semen.

The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called irradiation and radiotherapy.

Giving off radiation.

An unstable form of a chemical element that releases radiation as it breaks down and becomes more stable. Radioisotopes may occur in nature or be made in a laboratory. In medicine, they are used in imaging tests and in treatment. Also called radionuclide.

To come back or to return.

Cancer that has recurred (come back), usually after a period of time during which the cancer could not be detected. The cancer may come back to the same place as the original (primary) tumor or to another place in the body. Also called recurrence.

Something that may increase the chance of developing a disease. Some examples of risk factors for cancer include age, a family history of certain cancers, use of tobacco products, certain eating habits, obesity, lack of exercise, exposure to radiation or other cancer-causing agents, and certain genetic changes.

A picture of structures inside the body. Scans often used in diagnosing, staging, and monitoring disease include liver scans, bone scans, and computed tomography (CT) or computerized axial tomography (CAT) scans and magnetic resonance imaging (MRI) scans. In liver scanning and bone scanning, radioactive substances that are injected into the bloodstream collect in these organs. A scanner that detects the radiation is used to create pictures. In CT scanning, an x-ray machine linked to a computer is used to produce detailed pictures of organs inside the body. MRI scans use a large magnet connected to a computer to create pictures of areas inside the body.

In medicine, an instrument that takes pictures of the inside of the body.

Convulsion; a sudden, involuntary movement of the muscles.

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. SPECT can give information about blood flow to tissues and chemical reactions (metabolism) in the body. Also called single-photon emission computed tomography.

The study of the amount of light that is taken up, given off, or scattered (reflected) by an object. Spectroscopy breaks down light and measures different wavelengths of visible and non-visible light. In medicine, different types of spectroscopy are being used to study tissues and to help make a diagnosis.

The male reproductive cell, formed in the testicle. A sperm unites with an egg to form an embryo.

The bones, muscles, tendons, and other tissues that reach from the base of the skull to the tailbone. The spinal column encloses the spinal cord and the fluid surrounding the spinal cord. Also called backbone, spine, and vertebral column.

A column of nerve tissue that runs from the base of the skull down the back. It is surrounded by three protective membranes, and is enclosed within the vertebrae (back bones). The spinal cord and the brain make up the central nervous system, and spinal cord nerves carry most messages between the brain and the rest of the body.

The bones, muscles, tendons, and other tissues that reach from the base of the skull to the tailbone. The spine encloses the spinal cord and the fluid surrounding the spinal cord. Also called backbone, spinal column, and vertebral column.

A procedure to remove or repair a part of the body or to find out whether disease is present. An operation.

An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.

A set of symptoms or conditions that occur together and suggest the presence of a certain disease or an increased chance of developing the disease.

A type of germ cell tumor that may contain several different types of tissue, such as hair, muscle, and bone. Teratomas occur most often in the ovaries in women, the testicles in men, and the tailbone in children. Not all teratomas are malignant.

A group or layer of cells that work together to perform a specific function.

A surgical procedure in which tissue or an organ is transferred from one area of a person’s body to another area, or from one person (the donor) to another person (the recipient).

A genetic disorder in which benign (not cancer) tumors form in the kidneys, brain, eyes, heart, lungs, and skin. This disease can cause seizures, mental disabilities, and different types of skin lesions.

An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancer), or malignant (cancer). Also called neoplasm.

A substance that may be found in tumor tissue or released from a tumor into the blood or other body fluids. A high level of a tumor marker may mean that a certain type of cancer is in the body. Examples of tumor markers include CA 125 (in ovarian cancer), CA 15-3 (in breast cancer), CEA (in ovarian, lung, breast, pancreas, and gastrointestinal tract cancers), and PSA (in prostate cancer).

Fluid containing water and waste products. Urine is made by the kidneys, stored in the bladder, and leaves the body through the urethra.

A blood vessel that carries blood to the heart from tissues and organs in the body.

A fluid-filled cavity in the heart or brain.

The bones, muscles, tendons, and other tissues that reach from the base of the skull to the tailbone. The vertebral column encloses the spinal cord and the fluid surrounding the spinal cord. Also called backbone, spinal column, and spine.

A substance used to make plastics. Exposure to vinyl chloride may increase the risk of developing liver, brain, and lung cancers; lymphoma; and leukemia.

To eject some or all of the contents of the stomach through the mouth.

A rare inherited disorder in which blood vessels grow abnormally in the eyes, brain, spinal cord, adrenal glands, or other parts of the body. People with von Hippel-Lindau syndrome have a higher risk of developing some types of cancer. Also called VHL syndrome.

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.