An overview on the types of brain tumours, symptoms and risk factors from the National Neuroscience Institute (NNI).
What is brain tumour?
The brain contains many different types of cells, and as a result, there are more than 100 different kinds of brain tumours which can occur. These cancers can grow in brain cells, blood vessels, nerves or even the membranes that cover the brain.
There are two broad categories of brain tumours – primary and secondary. Primary brain tumours start in the brain. They are relatively uncommon, have no known cause and are rarely genetic. Secondary brain tumours start in organs such as the lung, breast or colon, and in time, move to the brain. They are the more common category seen.
Associate Professor Ng Wai Hoe, Senior Consultant and Medical Director,
Department of Neurosurgery,
National Neuroscience Institute (NNI), a member of the SingHealth group, said that 55 to 60 per cent of his brain cancer cases are secondary brain tumours. “In the past, patients generally succumbed to cancer before it got to their brains, but now, because they are surviving longer, cancers have time to spread to the brain.”
Who are at risk of developing brain tumours?
As cancer cases increase in Singapore, brain tumours are also set to rise, but it is hard to tell who is susceptible. “With regards to primary brain tumours, anyone who has two first-degree relatives like parents or siblings with brain tumours would be at slightly elevated risk of this but it’s rare. In most cases of brain tumours, patients have no family history of the condition,” said Prof Ng.
In general, people who are at slightly higher risk of brain tumours include those over 65 years old, Caucasians, men, and those who have been exposed to radiation therapy treatment for cancers such as leukaemia. There is no evidence that it is caused by mobile phone use, injury, or mental stress, said Prof Ng.
Brain tumour symptoms
Brain tumours are not as easy to detect as other common cancers, and symptoms vary according to location and size.
Function is usually affected first. If the tumour is in the section of the brain that controls vision or speech, the patient’s vision will become blurred and he will have problems finding the right words to express himself. If the tumour is located in a superficial part of the brain, it may cause seizures – the patient’s hands may jerk and he may see flashes of light.
A growing tumour may put pressure on the brain, causing headaches, nausea, vomiting and loss of appetite. “Any constant persistent headache with increasing severity, especially in the morning, warrants investigation,” said Prof Ng.
The increase in pressure can also lead to swelling of the nerves around the eyes. Prof Ng said: “I recently operated on a patient who had gone for a routine health screening. The doctor who examined his eyes noticed that the nerves around his eyes were swollen. A scan revealed that he had a brain tumour.”
However, Prof Ng said that many symptoms of brain tumours may not actually be caused by brain tumours, but by other illnesses. “It’s important to see a doctor if you have symptoms that persist or are bothersome.”
Read on to learn how brain tumour is treated.