What is Cancer
Cancer Type

Brain & spinal cord tumours

The brain and spinal cord
The brain and spinal cord make up the central nervous system (CNS). The CNS receives messages from cells called nerves, which are spread throughout the body (in the peripheral nervous system). The brain interprets information and relays messages through the nerves to muscles and organs.
 
The brain is the most important organ in the body because it controls all voluntary and involuntary processes, such as learning, sensing, imagining, remembering, breathing, blood circulation and heart rate, body temperature, digestion, and bowel and bladder control (continence). 
 
The main sections of the brain are the cerebrum (the largest part), the cerebellum and the brain stem. These parts play unique roles in the body's functions, many of which are essential to staying alive. Deep within the brain is the pituitary gland. It controls growth and development by releasing chemical messengers (hormones) into the blood. These signal other hormones to start or stop working.
 
The spinal cord extends from the brain stem to the lower back. It consists of nerve cells and nerve bundles that connect the brain to all parts of the body through the peripheral nervous system. The spinal cord is part of the spinal canal, along with fat, connective tissue and blood vessels. Bony vertebrae protect the spinal canal.
 
Both the brain and spinal cord are surrounded by membranes called meninges. Inside the skull and vertebrae (spinal column), the brain and spinal cord float in liquid called cerebrospinal fluid.
 

Nervous tissue
The brain, spinal cord and nerves consist of billions of nerve cells called neurons or neural cells, which process and send information. Together this is called nervous tissue.
The three main types of neural cells are:
  1. sensory neurons: respond to light, sound and touch
  2. motor neurons: cause muscle contractions
  3. interneurons: connect neurons in the brain and spinal cord
Glial cells, or neuroglia, are the other main type of cell in the nervous system. There are several different types of glial cells, including astrocytes and oligodendrocytes.
 
Glial cells are the glue of the nervous system because they surround the neurons and hold them in place. The glial cells also supply nutrients and oxygen to neurons and get rid of dead neurons and germs.
 
What is a brain or spinal cord tumour?
A tumour occurs when cells in the central nervous system grow and divide in an uncontrollable way, forming a lump. The lump may press on or grow into different areas of the brain or spinal cord, which can cause various symptoms such as loss of movement. A tumour can be benign or malignant, but sometimes it is difficult to tell the difference between them.
 
Benign tumours usually have slow-growing cells and clear borders (margins), and they rarely spread. However, they may be found in essential areas of the brain that control vital life functions, which can make them life-threatening.
 
Malignant tumours usually grow rapidly and spread within the brain and spinal cord. Malignant brain tumours can also be life-threatening. About 40% of brain and spinal cord tumours are malignant
What types are there?
There are more than 100 types of brain and spinal cord tumours (also called central nervous system or CNS tumours). They are usually named after the cell type they started in.
  • Benign tumours: The most common types are meningiomas, neuromas, cranio-pharyngiomas, pituitary tumours, and cystic astrocytomas. Benign tumours can cause problems by pressing on the brain and spinal cord. Most of these tumours can be removed by surgery, but if this is not possible, cancer treatments such as radiotherapy may be used.
  • Malignant tumours: These include high-grade astrocytomas, oligodendrogliomas, ependymomas, glioblastomas and mixed gliomas. In some malignant tumours, the cells are confined to one area. In other tumours, malignant cells are also found in surrounding tissue.
  • Metastatic brain tumours: These begin as cancer in another part of the body before spreading to the brain.
What are the causes?
The causes of most brain and spinal cord tumours are unknown. However, there are a few known risk factors for malignant brain tumours:
  • Radiotherapy: People who have had radiation to the head, usually to treat another type of cancer, may be at an increased risk of developing a tumour. This may affect people who had radiotherapy for childhood leukaemia.
  • Family history: It is possible to have a genetic predisposition to developing a tumour. This means that you may have a fault in your genes, passed down from your parents, that increases your risk. For example, some people have a genetic condition called neurofibromatosis, which causes nerve tissue to grow tumours.
  • Mobile phones: Some researchers have studied whether long-term or excessive use of mobile phones increases a person's risk of developing a brain tumour. It is possible that there may be an increased risk of developing a glioma in people with high levels of mobile phone use (i.e. more than 30 minutes a day). However, there is insufficient scientific evidence to link regular mobile phone use to brain tumours. Research is continuing in this area.
Symptoms
The symptoms of a brain or spinal cord tumour depend on where it is located and if it is causing pressure in the skull or spinal column. Sometimes, when a tumour grows slowly, symptoms develop gradually or you may not take much notice of them. They may be similar to other illnesses, such as a migraine or a stomach bug (e.g. headaches or nausea).
 
Brain and spinal cord tumours may cause weakness or paralysis in parts of the body. Some people also have trouble balancing or have seizures.
 
Other symptoms of brain tumours include:
  • nausea and/or vomiting
  • headaches
  • drowsiness
  • difficulty speaking or remembering words
  • short-term memory problems
  • disturbed vision, hearing, smell or taste
  • loss of consciousness
  • general irritability, depression or personality changes - this is sometimes only noticed by family or friends
Symptoms of spinal cord tumours include:
  • back and neck pain
  • numbness or tingling in the arms or legs
  • clumsiness or difficulty walking
  • loss of bowel or bladder control (incontinence)
How common is it?
According to Globocan (2012), brain cancer is the 2nd most common type of cancer in children below the age of 14. In adults, it comprises of 2.1% of registered cases in Malaysia.
Information Reviewed By:
Prof. Michael Besser AM, Consultant Emeritus in Neurosurgery, Royal Prince Alfred Hospital & The Children's Hospital at Westmead; Lindy Cohn, Helpline, Cancer Council NSW; Laraine Cross, Senior Clinician, Social Work, Calvary Mater Newcastle; Christine and Richard Harris, Christine and Gordon Holding, Consumers; Marina Kastelan, Brain Clinical Nurse Coordinator, North Shore Private Hospital; Lorna O'Brien, Helplline Manager, Cancer Council NSW; and Karen Robinson, Neuro-oncology Care Coordinator, Liverpool Hospital Cancer Therapy Centre. Carcinoid tumours