Pontine gliomas are malignant (cancerous) tumours that originate from the part of the brain known as the brain stem (pons). They develop from cells called astrocytes. Astrocytomas are the most common type of glioma. You will often hear the terms astrocytoma and glioma used interchangeably. In children, 80% of brain stem tumours are pontine gliomas.
If a biopsy is carried out they are usually found to be high grade gliomas and are classified according to the grade of aggressiveness (how quickly they grow) as either anaplastic astrocytomas (grade III) or glioblastoma multiforme (GBM). These tumours grow amongst the normal nerve cells of the brain stem making them impossible to remove surgically as the brain stem is a vital area of the brain that controls many body functions.
Who gets pontine glioma?
Less than 40 children a year develop pontine glioma in the UK. This is around 10-15% of all childhood brain tumours. They rarely occur in adults. Like most brain tumours, the cause of pontine gliomas is unknown.
Signs and symptoms
The symptoms are related to the internal pressure that the tumour applies on the brain stem. Occasionally they can cause increased pressure in the head (raised intracranial pressure). Rarely they spread into the spine. Symptoms include:
- swallowing problems
- slurred speech
- facial weakness
- abnormal gait (the way the child walks)
- difficulty with tasks like handwriting
- gradual decline in school work
- changes in personality and behaviour.
If there is increased pressure in the head:
- nausea and vomiting.
If the tumour spreads to the spine:
- back pain
- difficulty walking
- problems with bowel and bladder control.
Tests / investigations
We will need to carry out some tests to find out as much as possible about the type, position and size of the tumour. This will help us to decide on the best treatment for your child. These tests include:
- CT scan – it is likely a CT scan of your child’s brain was the first specific test carried out at your local hospital. Although MRI scans are usually the best way of seeing the tumour and the effects of treatment, sometimes CT scans are also useful.
- MRI scan – this scan allows us to see the brain and spine in great detail and is used regularly to diagnose and follow the effect treatment is having on your child’s tumour.