What is a brain or spinal cord tumour?

A brain tumour starts in the cells of the brain. A spinal cord tumour starts in the cells of the spinal cord. Together, the brain and spinal cord form the central nervous system (CNS). The brain is the control centre of your body. It is a soft mass of nerve tissue protected by a bony covering called the skull. The spinal cord runs through the spine. It contains nerves that send information between the brain and the rest of the body.

Diagram of the central nervous system
Diagram of the central nervous system

Cells in the brain or spinal cord sometimes change and no longer grow or behave normally. These changes may lead to non-cancerous (benign) conditions such as brain or spinal cord cysts. Cells in the brain and spinal cord can also change and form tumours. All brain and spinal cord tumours can cause severe or life-threatening symptoms.

Brain and spinal cord tumours are classified based on their grade. The grade of a tumour tells your healthcare team how quickly it is growing and how likely it is to spread.

Low-grade (non-cancerous) tumours grow slowly. They don’t usually grow into surrounding tissues or spread to other areas of the brain or spinal cord. Some low-grade tumours may develop into high-grade tumours.

High-grade (cancerous) tumours grow quickly. They can grow into nearby tissues and spread to other parts of the brain or spinal cord. Cancerous tumours that start in the brain and spinal cord rarely spread outside the CNS.

Types of brain and spinal cord tumours

Glioma is a general term for a group of tumours that start in glial cells that are the supportive cells of the brain or spinal cord. They are the most common type of primary brain tumours in adults and account for most of the cancerous (high-grade) tumours of the CNS. There are different types of gliomas, including astrocytoma, oligodendroglioma and ependymomas.

Brain and spinal cord tumours can also start in the cells of the meninges. The meninges are the membranes that cover the brain and spinal cord. These tumours are called meningiomas. Low-grade meningiomas are the most common type of non-cancerous brain and spinal cord tumour in adults.

There are many less common types of brain and spinal cord tumours including acoustic neuroma, craniopharyngioma, hemangioblastoma and primary central nervous system lymphoma.

Some types of brain and spinal cord tumours are more common in children and others are more common in adults. Find out more about brain and spinal cord tumours in children.

Brain metastasis

When a tumour starts in brain cells, it is called a primary brain tumour. Other types of cancer can spread to the brain, but this is not the same disease as a primary brain tumour. Cancer that starts in another part of the body and spreads to the brain is called brain metastasis or a secondary tumour. It is not treated in the same way as a primary brain tumour. Find out more about brain metastasis.

Expert review and references

  • American Cancer Society. Brain and Spinal Cord Tumors in Adults. 2014: https://www.cancer.org/.
  • American Society of Clinical Oncology . Brain Tumor . 2015 .
  • Chang S, Mehta M, Vogelbaum M, Taylor M, Ahluwalia M . Neoplasms of the central nervous system. DeVita VT Jr, Lawrence TS, & Rosenberg SA. Cancer: Principles and Practice of Oncology. 10th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2015: 97:1412-1455.

The brain and spinal cord

The brain is a spongy organ made up of nerve and supportive tissues. It is located in the head and is protected by the boney covering called the skull. The base or lower part of the brain is connected to the spinal cord. Together, the brain and spinal cord are known as the central nervous system (CNS).

Astrocytoma

Glioma is a general term for a group of tumours that start in the supportive tissues (glial cells) of the brain or spinal cord. They are the most common type of primary brain tumours in adults and account for about 70% of all malignant (high-grade) tumours of the central nervous system (CNS).

Oligodendroglioma

Glioma is a general term for a group of tumours that start in the supportive tissues (glial cells) of the brain or spinal cord. They are the most common type of primary brain tumours in adults and account for about 70% of all malignant (high-grade) tumours of the central nervous system (CNS).

Ependymoma

Glioma is a general term for a group of tumours that start in the supportive tissues (glial cells) of the brain or spinal cord. They are the most common type of primary brain tumours in adults and account for about 70% of all malignant (high-grade) tumours of the central nervous system (CNS).

Meningioma

Meningioma starts in the cells of the membranes that cover the brain and spinal cord (meninges). Meningiomas can be low to high grade. Grade 1 is the most common type of meningioma. Meningiomas account for approximately 1 out of 3 primary brain and spinal cord tumours.

Other brain and spinal cord tumours

Many less common types of benign (low-grade) and malignant (high-grade) brain and spinal cord tumours happen in adults.

Brain and spinal cord metastases

Metastatic tumours happen when a cancer spreads to the brain or spinal cord from its original site in another area of the body. The most common way for metastases to spread is through the blood.

Brain and spinal cord cysts

Benign conditions of the brain and spinal cord are non-cancerous. Cysts are sacs that contain fluid or semi-solid material. Cysts found in the brain and spinal cord may contain cerebrospinal fluid, blood, tissue or tumour cells.

Medical disclaimer

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