Types of brain and spinal cord tumours

There are many different types of brain and spinal cord tumours. The World Health Organization (WHO) has a classification system to describe these tumours that develop in the central nervous system, or CNS. (Together, the brain and spinal cord are known as the central nervous system.) The most recent version of the classification system is WHO CNS5, released in 2021.

In the WHO CNS5 classification system:

• Brain and spinal cord tumours are separated into adult types of tumours and childhood (pediatric) types of tumours. This is because some types of tumours are found mostly in adults, and other types of tumours are found mostly in children.

• Genetic alterations, which are changes found in the cancer cells, are key to diagnosing, classifying and grading a tumour. Genetic alterations include gene mutations, as well as changes to the chromosomes such as deletions, translocations or insertions.

• The grade of the tumour is also used to classify different types of brain and spinal cord tumours.

• Some types of brain and spinal cord tumours are also described according to where they start in the CNS.

Most brain and spinal cord tumours are non-cancerous, but they can still cause problems if they continue to grow inside the CNS. They can put pressure on the surrounding tissues and cause symptoms. Non-cancerous brain and spinal cord tumours may need to be treated to prevent any further complications or problems.

WHO CNS5 lists more than 100 different types and subtypes of CNS tumours. Some of the most common types of adult brain and spinal cord tumours are as follows.

Gliomas are tumours that start in the different glial cells of the brain that support the nerve cells and help them work properly. There are many different types of gliomas. They are one of the most common types of primary brain tumours in adults.

The following are the most common types of gliomas.

Glioblastoma (IDH-wild type) is a tumour that starts in the astrocyte cells. Your healthcare team may just call it a glioblastoma.

It is the most aggressive type of brain tumour. IDH-wild type means that there are no changes to the IDH (isocitrate dehydrogenase) gene. IDH makes an enzyme that helps cells break down fats and protects them from harmful substances. Glioblastoma (IDH-wild type) tumours will not respond to treatments designed to treat tumours that have mutations to this gene (IDH-mutant tumours).

All glioblastomas are grade 4 tumours.

In earlier versions of the WHO classification system, glioblastoma (IDH-wild type) was called glioblastoma multiforme (GBM) or grade 4 astrocytoma.

Astrocytoma (IDH-mutant) is a tumour that starts in the astrocyte cells. Your healthcare team may just call it an astroyctoma.

Almost all astrocytomas have a mutation (change) in the IDH gene, but a very small number may not have this mutation. Other types of gene alterations may also be found in these tumours.

Astrocytoma (IDH-mutant) can be grade 2, 3 or 4.

In earlier versions of the WHO classification system, grade 2 astrocytoma was called a low-grade glioma and grade 3 was called an anaplastic astrocytoma.

Oligodendroglioma is a tumour that starts in the oligodendrocyte cells. Your healthcare team may just call it an oligodendroglioma.

It has an IDH mutation along with certain changes to chromosomes. Chromosomes 1 and 19 are both missing pieces (co-deleted). Chromosome 1 is missing the short arm (p) and chromosome 19 is missing the long arm (q).

Oligodendroglioma (IDH-mutant and 1p/19q-codeleted) can be grade 2 or 3.

Oligodendroglioma sometimes spreads to the cerebrospinal fluid (CSF).

Meningioma is a tumour that start in the cells of the meninges (the membranes that cover the brain and spinal cord). Meningiomas are more common in women and they are often non-cancerous.

There are several different types of gene alterations that are found in meningiomas, including changes to NF2, AKT1, PIK3CA and TERT promoters.

Meningiomas can be grade 1, 2 or 3.

Ependymoma is a tumour that starts in the ependymal cells lining the fluid-filled spaces of the brain called the ventricles, and the fluid space around the spinal cord.

There are several different types of ependymoma and they are named according to where they are found in the CNS. The most common type of ependymoma found in adults is spinal ependymoma.

Ependymoma tumours may have genetic alterations in ZFTA, YAP1 and MYCN genes.

Ependymoma tumours are grades 2 or 3.

There are many types of adult brain and spinal cord tumours that are less common. These tumours account for less than 1% of all brain tumours:

• glioneuronal and neuronal tumours (such as ganglioglioma, and neurocytoma)
• choroid plexus tumours (tumours that start in the ventricles of the brain)
• tumours of the pineal gland (such as pineoblastoma and pineocytoma)
• nerve tumours (such as acoustic neuroma, neurofibroma and nerve sheath tumours)
• blood vessel tumours (such as hemangioblastoma and hemangioma)
• craniopharyngioma (tumours that start near the pineal gland)

Treatment for these tumours may include surgery, radiation therapy, chemotherapy or a combination of treatments.

Some tumours are actually different types of cancer that started in the brain or spinal cord, such as:

• soft tissue sarcoma (such as rhabdomyosarcoma, chondrosarcoma, chordoma and primary intracranial sarcoma)
• melanoma
• bone tumours
• non–Hodgkin lymphoma (such as primary diffuse large B-cell lymphoma)
• germ cell tumours (such as choriocarcinoma, embryonal carcinoma)
• pituitary gland tumours

These tumours are treated according to their cancer type.

The most common types of tumours that develop in the spinal cord are:

• meningioma
• astrocytoma
• ependymoma
• chordoma
• hemangioblastoma
• schwannoma

Intradural spinal tumours are tumours that start in the spinal cord or in the covering of the spinal cord (called the dura). Intradural spinal tumours can be further classified as:

• intramedullary – tumours that start in the cells of the spinal cord (astrocytoma, ependymoma, glioma)
• extramedullary – tumours that start in the covering of the spinal cord (meningioma, schwannoma)

Tumours that start in the bone (vertebrae) of the spine are a type of primary bone cancer.

When a tumour starts in the cells of the brain or spinal cord, it is called a primary brain or primary spinal cord tumour.

Cancer that starts in another part of the body and spreads to the brain is called a brain metastasis. Brain metastases are much more common than primary brain tumours, and they are not treated in the same way as primary brain tumours.

Some cancers can also spread to the meninges, the thin layer of tissue that covers the brain and spinal cord. This is called leptomeningeal metastasis or meningeal carcinomatosis.

Find out more about brain metastases.

Cancer can spread to the bones of the spine from other parts of the body. This is called bone metastasis. Find out more about bone metastases.