What is childhood visual pathway glioma?

Childhood visual pathway glioma is a type of brain tumor in which cancer (malignant) cells begin to grow in the tissues of the brain. The brain controls 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 or lymphoma, brain tumors are the most common type of cancer that occurs in children.

Gliomas are a type of astrocytoma, tumors that start in brain cells called astrocytes. A visual pathway glioma occurs along the nerve that sends messages from the eye to the brain (the optic nerve ). Visual pathway gliomas are visual pathway tumors. They may grow rapidly or slowly, depending on the grade of the tumor.

The risk of developing visual pathway gliomas is increased in children with a genetic disorder called neurofibromatosis type 1 (NF-1). NF-1 is 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. Children with NF-1 who develop visual pathway gliomas may have a good chance of recovery and may not require treatment until symptoms appear or change.

This PDQ summary covers tumors that start in the brain ( primary brain tumors). Often cancer found in the brain has started somewhere else in the body and has spread ( metastasized ) to the brain. This is called brain metastasis (refer to the PDQ summary on Adult Brain Tumors Treatment for more information).

Like most cancer, childhood brain tumor is best treated when it is found ( diagnosed ) early. If your child has symptoms, the doctor may order a computed tomographic (CT) scan, a special x-ray that uses a computer to make a picture of your child’s brain. A magnetic resonance imaging (MRI) scan, which uses magnetic waves to make a picture of your child’s brain, may also be done.

Often, surgery is required to see whether there is a brain tumor and to tell what type of tumor it is. The doctor may cut out a piece of tissue from the brain and look at it under a microscope. This is called a biopsy.

There are many types of brain tumors in children and the chance of recovery ( prognosis ) depends on the type of tumor, where it is located within the brain, and your child’s age and general health. See the PDQ summary on Childhood Brain and Spinal Cord Tumors Treatment Overview for more information about the types of childhood brain tumors.