What is childhood brain tumor?

Note: The health professional version ¹ of this summary was extensively revised in April 2008. The patient version of this summary will reflect these changes soon.

Childhood brain tumors are a diverse group of diseases characterized by the abnormal growth of tissue contained within the skull. Brain tumors can be benign (without cancer cells) or malignant (contains cancer cells). The brain controls vital functions such as memory and learning, the senses (hearing, sight, smell, taste, and touch), and emotion. It also controls other parts of the body, including muscles, organs, and blood vessels. Other than leukemia and lymphoma, brain tumors are the most common type of cancer that occurs in children.

This PDQ treatment information summary refers only to tumors that originate in the brain (primary brain tumors). Metastatic brain tumors, which are secondary tumors formed by cancer cells that begin in other parts of the body and spread to the brain, are not included. Brain tumors can occur in both children and adults; however, treatment may be different for adults than for children. (Refer to the PDQ summary on Adult Brain Tumor Treatment ² for more information.)

If your child has symptoms that may be caused by a brain tumor, his or her doctor may order a computed tomographic (CT) scan, a diagnostic test that uses computers and x-rays to create pictures of the body. A magnetic resonance imaging (MRI) scan, a diagnostic test similar to a CT scan but which uses magnetic waves instead of x-rays, may also be performed.

Often, surgery is required to determine whether a brain tumor exists and what type of tumor it is. A small sample of tumor tissue may be surgically removed and examined under a microscope. This is called a biopsy. Sometimes a biopsy is done by making a small hole in the skull and using a needle to extract a sample of the tumor.

There are many types of brain tumors that occur in children. Treatment and chance of recovery (prognosis) depend on the type of tumor, its location within the brain, the extent to which it has spread, and your child’s age and general health.

Glossary Terms

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

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.

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

The growth of abnormal cells in the tissues of the brain. Brain tumors can be benign (non-cancerous) or malignant (cancerous).

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.

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

CT scan. 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 CT scan, computerized tomography, computerized axial tomography scan, and CAT scan.

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.

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.

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. Magnetic resonance imaging makes better images of organs and soft tissue than other scanning techniques, such as computed tomography (CT) or x-ray. Magnetic resonance imaging is especially useful for imaging the brain, the spine, the soft tissue of joints, and the inside of bones. Also called MRI, nuclear magnetic resonance imaging, and NMRI.

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

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

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

The original tumor.

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

A term that is used to describe either a new primary cancer or cancer that has spread from the place in which it started to other parts of the body.

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

Necessary to maintain life. Breathing is a vital function.

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.