Glossary

Below are brief descriptions of the most common brain tumors, with more descriptions provided by the National Cancer Institute.

Acoustic Neuroma
A benign tumor affecting the vestibular nerve and causing hearing loss, a ringing in the ear, and occasionally unsteadiness.

Cerebrospinal fluid
A clear, colorless, bodily fluid, that the brain and spinal cord "float" in. The fluid acts as a cushion, protecting the brain inside the skull.

Ependymoma
A type of brain tumor that begins in the choroid plexus, which makes the cerebrospinal fluid that fills parts of the brain.

Glioma
A brain cancer that begins in the glial cells that surround and support nerve cells.

Hemangioblastoma
A usually non-cancerous tumor made up of stem cells that the body uses to make blood vessels or blood cells.

Meningioma
A slow-growing tumor that forms in the thin layers of tissue that cover and protect the brain and spinal cord.

Metastatic
Any tumor resulting from the spread of cancer to another part of the body from where it started

Osteoma
A piece of bone usually growing on another piece of bone in the skull. It is a benign lesion.

Pituitary Tumor
A normally benign tumor that forms in the pituitary gland, a pea-sized organ in the center of the brain above the back of the nose that makes hormones that affect other glands and many body functions, especially growth.

Skull Base Tumor
Any tumor that starts at the base of the skull though which the spinal chord and major blood vessels and nerves pass.