Key Points for This Section

The grade of the tumor is used in place of a staging system to plan cancer treatment. The information from tests and procedures done to detect (find) childhood cerebellar astrocytoma is used to plan cancer treatment.

The grade of the tumor is used in place of a staging system to plan cancer treatment.

Staging is the process used to find out how much cancer there is and if cancer has spread. It is important to know the stage in order to plan treatment.

There is no standard staging system for childhood cerebellar astrocytoma. Instead, the grade of the tumor is used to plan treatment. The grade of the tumor describes how abnormal the cancer cells look under a microscope and how quickly the tumor is likely to grow and spread.

The following grades are used:

• Grade I pilocytic tumor is a tumor that is very slow-growing and rarely spreads. These tumors form inside cysts.
• Grade II diffuse or fibrillary tumor is a tumor that usually spreads slowly within the cerebellum.

Cerebellar astrocytomas usually do not spread from the cerebellum to other parts of the brain or body.

The information from tests and procedures done to detect (find) childhood cerebellar astrocytoma is used to plan cancer treatment.

Some of the tests used to detect childhood cerebellar astrocytoma are repeated after the tumor is removed. (See the General Information ¹ section.) This is to find out how much tumor remains after surgery and plan further treatment.

Glossary Terms

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

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

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.

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.

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

Widely spread; not localized or confined.

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.

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

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 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.