Childhood Cerebellar Astrocytoma

by National Cancer Institute

Childhood cerebellar astrocytoma is a disease in which benign (noncancer) or malignant (cancer) cells form in the tissues of the brain.

Astrocytomas are tumors that develop from brain cells called astrocytes. Cerebellar astrocytomas start in the cerebellum, which is located at the lower back of the brain. The cerebellum is the part of the brain that controls movement, balance, and posture.

About 15-25% of all childhood brain tumors are cerebellar astrocytomas. Although cancer is rare in children, brain tumors are the most common type of childhood cancer other than leukemia and lymphoma.

This summary refers to the treatment of primary brain tumors (tumors that begin in the brain). Treatment for metastatic brain tumors, which are tumors formed by cancer cells that begin in other parts of the body and spread to the brain, is not discussed in this summary.

Brain tumors can occur in both children and adults; however, treatment for children may be different than treatment for adults. (Refer to the PDQ treatment summary on Adult Brain Tumors for more information.)

The cause of most childhood brain tumors is unknown.

The symptoms of childhood cerebellar astrocytoma vary and often depend on the child's age and where the tumor is located.

These symptoms may be caused by an astrocytoma or other conditions. A doctor should be consulted if any of the following problems occur:

• Loss of balance, difficulty walking, worsening handwriting, or slow speech.
• Morning headache or headache that goes away after vomiting.
• Nausea and vomiting.
• Unusual sleepiness or change in energy level.
• Change in personality or behavior.
• Unexplained weight loss or weight gain.

Tests that examine the brain and spinal cord are used to detect (find) childhood cerebellar astrocytoma.

The following tests and procedures may be used:

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): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the brain and spinal cord. A substance called gadolinium is injected into the patient through 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).

Childhood cerebellar astrocytoma is diagnosed and removed in surgery.

If a brain tumor is suspected, a biopsy is done by removing part of the skull and using a needle to remove a sample of the brain tissue. A pathologist views the tissue under a microscope to look for cancer cells. If cancer cells are found, the doctor will remove as much tumor as safely possible during the same surgery.

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

The prognosis (chance of recovery) depends on:

• The type of astrocytoma.
• Whether cancer cells remain after surgery.

Treatment options depend on:

• Whether cancer cells remain after surgery or have spread to other parts of the brain.
• The location of the tumor.
• The child's age.

Stages of Childhood Cerebellar Astrocytoma

After the childhood cerebellar astrocytoma has been removed, tests are done to find out if there is tumor remaining. The extent or spread of cancer is usually described as stages. For childhood cerebellar astrocytoma, the grade of the tumor is used instead of stages. The grade of the tumor refers to how abnormal the cancer cells look under a microscope and how quickly the tumor is likely to grow and spread. It is important to know the grade of the tumor and if there were any cancer cells remaining after surgery in order to plan treatment.

There are two grades for childhood cerebellar astrocytoma:

• Grade I pilocytic tumors are very slow-growing and rarely spread. These tumors form inside cysts.

• Grade II diffuse or fibrillary tumors spread slowly within the brain.

The following procedure may be used to determine if any cancer cells remain in the brain after surgery:

MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the brain and spinal cord. A substance called gadolinium is injected into the patient through 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).

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

Recurrent Childhood Cerebellar Astrocytoma

Recurrent childhood cerebellar astrocytoma is a tumor that has recurred (come back) after it has been treated. Childhood cerebellar astrocytoma may recur many years after initial treatment. The tumor may recur at the same place in the brain or in other parts of the central nervous system (brain and spinal cord), especially if the original tumor was a diffuse or fibrillary tumor.

About the Author

www.nci.nih.gov
The National Cancer Institute's research programs are extensive and contain many innovative initiatives. I invite you to explore our Web site to find out more about the exciting work being conducted here at NCI and by NCI-supported scientists throughout the country.