According to the National Brain Tumor Society, there are more than 120 types of brain and central nervous system (CNS) tumors, many with their own multitude of subtypes.
Common Types of Brain and Spinal Tumors
Brain tumors can be broken down into two broad categories: gliomas and non-gilomas.
As a group, gliomas are one of the most common types of brain tumors, accounting for about 33% of all brain tumors. Gliomas originate in the glial (supportive) tissue. Astrocytoma, which starts in the glial cells called astrocytes, is the most common type of glioma, accounting for about 2 out of 10 brain tumors.
Non-glioma tumors are tumors that arise from cells in the brain that are not glial cells. Meningioma is the most common primary brain tumor. These tumors originate in the meninges, the layers of tissue that surround the outer part of the brain and spinal cord.
Less Common Types of Brain and Spinal Tumors
Other brain and spinal tumors are less common. These either account for a very low percentage of brain and spinal tumors or are more common among children than adults.
Less common glioma tumors include:
- Oligodendroglioma. Begins in brain glial cells called oligodendrocytes. About 4% of primary brain tumors are oligodendrogliomas.
- Ependymoma. A tumor that starts in the ependymal cells that line the ventricles. They account for 2-3% of primary brain tumors.
- Brain stem glioma. A tumor that begins in the glial cells in the brain stem.
Less common non-glioma tumors include:
- Schwannoma. A tumor that begins in the nerve sheath, or the lining of the nerves.
- Medulloblastomas. A tumor that develops from neuroectodermal cells (early forms of nerve cells) in the cerebellum. Medulloblastomas occur much more often in children than in adults.
- Craniopharyngioma. Tumor that starts above the pituitary gland but below the brain. Craniopharyngiomas are more common in children, but they are sometimes seen in adults.
- Primary CNS lymphoma. A form of lymphoma that starts in the brain and can spread to the spinal fluid and eyes.
- Pituitary tumors. Tumors that start in the pituitary gland. In most cases, pituitary tumors are benign, slow-growing masses that represent about 10% of primary brain tumors.