Brain Stem Gliomas
Pineal Astrocytic Tumor
Pilocytic Astrocytoma (grade I)
Diffuse Astrocytoma (grade II)
Anaplastic Astrocytoma (grade III)
Glioblastoma (grade IV)
Oligodendroglial Tumors
Mixed Gliomas
Ependymal Tumors
Medulloblastoma (grade IV)
Pineal Parenchymal Tumors
Meningeal Tumors
Germ Cell Tumor
Craniopharyngioma (grade II)
Other Adult Brain Tumors
Recurrent Adult Brain Tumor
Metastatic Brain Tumors

The extent or spread of cancer is usually described as stages. There is no standard staging system for brain tumors. Primary brain tumors may spread within the central nervous system (brain and spinal cord), but they rarely spread to other parts of the body. For treatment, brain tumors are classified by the type of cell in which the tumor began, the location of the tumor in the central nervous system, and the grade of the tumor.

Types of adult brain tumors include the following:

These are tumors that form in the brain stem, the part of the brain connected to the spinal cord. They are often high-grade. Brain stem gliomas that are high-grade or spread widely throughout the brain stem are difficult to treat successfully. To prevent damage to healthy brain tissue, brain stem glioma is usually diagnosed without a biopsy.

(Refer to the PDQ summary on Childhood Brain Stem Glioma Treatment ¹ for more information.)

Pineal tumors form in or near the pineal gland. The pineal gland is a tiny organ in the brain that produces the hormone melatonin, a substance that helps control our sleeping and waking cycle. There are several kinds of pineal tumors. Pineal astrocytic tumors are astrocytomas that occur in the pineal region and may be any grade.

Astrocytomas are tumors that start in brain cells called astrocytes. Pilocytic astrocytomas grow slowly and rarely spread into the tissues around them. These tumors occur most often in children and young adults. They usually can be treated successfully.

Diffuse astrocytomas grow slowly, but they often spread into nearby tissues. Some of them progress to a higher grade. They occur most often in young adults.

Anaplastic astrocytomas are also called malignant astrocytomas. They grow rapidly and spread into nearby tissues. The tumor cells look different from normal cells. The average age of patients developing anaplastic astrocytomas is 41 years.

Glioblastomas are malignant astrocytomas that grow and spread aggressively. The cells look very different from normal cells. Glioblastoma is also called glioblastoma multiforme or grade IV astrocytoma. They occur most often in adults between the ages of 45 and 70 years.

Refer to the following PDQ summaries for more information on astrocytomas:

• Childhood Cerebral Astrocytoma/Malignant Glioma Treatment ²
• Childhood Cerebellar Astrocytoma Treatment ³
• Childhood Visual Pathway and Hypothalamic Glioma Treatment ⁴

Oligodendroglial tumors begin in the brain cells called oligodendrocytes, which support and nourish nerve cells. Grades of oligodendroglial tumors include the following:

• Oligodendroglioma (grade II): Oligodendrogliomas are slow-growing tumors with cells that look very much like normal cells. These tumors occur most often in patients between the ages of 40 and 60 years.
• Anaplastic oligodendroglioma (grade III): Anaplastic oligodendrogliomas grow quickly and the cells look very different from normal cells.

Mixed gliomas are brain tumors that contain more than one type of cell. The prognosis is affected by the cell type with the highest grade present in the tumor.

• Oligoastrocytoma (grade II): Oligoastrocytomas are slow-growing tumors composed of cells that look like astrocytes and oligodendrocytes.
• Anaplastic oligoastrocytoma (grade III): These are higher-grade oligoastrocytomas. The average age of patients developing anaplastic oligoastrocytomas is 45 years.

Ependymal tumors usually begin in cells that line the spaces in the brain and around the spinal cord. These spaces contain cerebrospinal fluid, a liquid that cushions and protects the brain and spinal cord. Grades of ependymal tumors include the following:

• Grade I and grade II ependymomas: These ependymomas grow slowly and have cells that look very much like normal cells. They can often be removed completely by surgery.
• Anaplastic ependymoma (grade III): Anaplastic ependymomas grow very quickly.

(Refer to the PDQ summary on Childhood Ependymoma Treatment ⁵ for more information.)

Medulloblastomas are brain tumors that begin in the lower back of the brain. They are formed from abnormal brain cells at a very early stage in development. Medulloblastomas are usually found in children or young adults between the ages of 21 and 40 years. This type of cancer may spread from the brain to the spine through the cerebrospinal fluid.

(Refer to the PDQ summary on Childhood Medulloblastoma Treatment ⁶ for more information.)

Pineal parenchymal tumors form from parenchymal cells or pinocytes, the cells that make up most of the pineal gland. These differ from pineal astrocytic tumors, which are astrocytomas that form in tissue that supports the pineal gland. Grades of pineal parenchymal tumors include the following:

• Pineocytomas (grade II): Pineocytomas are slow-growing pineal tumors that occur most often in adults aged 25 to 35.
• Pineoblastomas (grade IV): Pineoblastomas are rare and highly malignant. They usually occur in children.

(Refer to the PDQ summary on Childhood Supratentorial Primitive Neuroectodermal Tumors and Pineoblastoma Treatment ⁷ for more information.)

Meningeal tumors form in the meninges, thin layers of tissue that cover the brain and spinal cord. Types of meningeal tumors include the following:

• Grade I meningioma: Meningiomas are the most common meningeal tumor. Grade I meningiomas are slow-growing and benign. They are found most often in women.
• Grade II and III meningiomas and hemangiopericytomas: These are rare malignant meningeal tumors. They grow quickly and are likely to spread within the brain and spinal cord. Grade III meningiomas are more common in men. Hemangiopericytomas often recur after treatment and most of them spread to other parts of the body.

Germ cell tumors arise from germ cells, cells that are meant to form sperm in the testicles or eggs in the ovaries, These cells may travel to other parts of the body and form tumors. Types of germ cell tumors include germinomas, embryonal cell carcinomas, choriocarcinomas, and teratomas. They can occur anywhere in the body and can be either benign or malignant. In the brain, they usually form in the center, near the pineal gland, and can spread to other parts of the brain and spinal cord. Most germ cell tumors occur in children.

(Refer to the PDQ summary on Childhood Brain and Spinal Cord Tumors Treatment Overview ⁸ for more information.)

Craniopharyngiomas occur in the sellar region of the brain, near the pituitary gland. The pituitary gland is a small organ about the size of a pea, located at the base of the brain. This gland controls many of the body's functions, especially growth. In adults, these tumors occur most often after the age of 50 years. Craniopharyngiomas can press on vital brain tissue and cause symptoms to appear. The tumors can also block fluid in the brain and cause swelling. The prognosis is good for craniopharyngiomas that are completely removed in surgery.

Pituitary tumors also occur in this region. Refer to the PDQ summary on Pituitary Tumor Treatment ⁹ for more information.

For information about other types of adult brain tumors, refer to the PDQ health professional summary on Adult Brain Tumors ¹⁰.

Recurrent adult brain tumor is a tumor that has recurred (come back) after it has been treated. Adult brain tumors often recur, sometimes many years after the first tumor. The tumor may come back in the brain or in other parts of the body.

The types of cancer that commonly spread to the brain are melanoma and cancers of the lung, breast, unknown primary site, and colon. About half of metastatic spinal cord tumors are caused by lung cancer.

Prognosis depends on the following:

• Whether the patient is younger than 60 years.
• Whether there are fewer than 3 tumors in the brain and/or spinal cord.
• The location of the tumors in the brain and/or spinal cord.
• 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

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

A quickly growing cancer.

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

A star-shaped cell that helps nerve cells in the brain and spinal cord 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 cancerous. Benign tumors may grow larger but do not 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.

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 (non-cancerous) or malignant (cancerous).

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. Cancer cells can invade nearby tissues and can 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.

CNS. The brain and spinal cord. Also called CNS.

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.

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.

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 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.

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

Widely spread; not localized or confined.

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.

Liquid.

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.

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 grade IV astrocytoma, glioblastoma multiforme, and GBM.

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.

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.

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.

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 spread of cancer from one part of the body to another. A tumor formed by cells that have spread is called a “metastatic tumor” or a “metastasis.” The metastatic tumor contains cells that are like those in the original (primary) tumor. The plural form of metastasis is metastases (meh-TAS-tuh-SEEZ).

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 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 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 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.

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

One of a pair of female reproductive glands in which the ova, or eggs, are formed. The ovaries are located in the pelvis, one on each side of the uterus.

The essential or functional elements of an organ.

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.

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 or pineal organ.

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

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.

The original tumor.

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

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 recurrent cancer.

In medicine, an improvement related to treatment.

A depression of the bone at the base of the skull where the pituitary gland is located.

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

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.

The extent of a cancer in the body. Staging is usually based on the size of the tumor, whether lymph nodes contain cancer, and whether the cancer has spread from the original site to other parts of the body.

Performing exams and tests to learn the extent of the cancer within the body, especially whether the disease has spread from the original site to other parts of the body. It is important to know the stage of the disease in order to plan the best treatment.

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 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.

One of two egg-shaped glands found inside the scrotum that produce sperm and male hormones. Also called a testis.

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

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 cancerous), or malignant (cancerous). Also called neoplasm.

Necessary to maintain life. Breathing is a vital function.