Glioma
Frequently asked questions
What is a mixed glioma?
A mixed glioma is a glioma brain tumour that contains a mix of glial cells including astrocytes, oligodendrocytes and ependymal cells.
Why are there different names for different types of glioma brain tumours?
All glioma brain tumours tend to be named to reflect the type of cells that make up the majority of the tumour.
This is determined through a biopsy or a surgical operation where a sample of the tumour is viewed by clinicians through a microscope (known as histopathological assessment) and classified by the physical characteristics that can be observed (known as the phenotype).
Some glioma brain tumours have different names depending upon their grade: for example they may be called a low-grade glioma or a grade 4 glioblastoma multiforme (GBM).
Is glioma a low-grade (benign) or high-grade (malignant) brain tumour?
The grade of a glioma brain tumour gives an indication as to how the tumour is expected to behave (develop).
All brain and central nervous system (CNS) tumours are divided into four tumour types – grades 1 to 4. These grades are based on cells examined using a microscope as well as genetic and epigenetic changes that are discovered during molecular testing in a laboratory.
Grade 1 glioma (low-grade glioma): Grade 1 gliomas are usually occur in children and teenagers. They are the most slow-growing (low-grade) form of glioma brain tumour and carry the longest prognosis. The most common form of low-grade glioma is a pilocytic astrocytoma, which rarely progresses to a higher grade and can sometimes be completely removed by surgery .
Grade 2 glioma (low-grade glioma): Grade 2 gliomas are more common in adults but can also occur in children and teenagers. They are initially a slow-growing (low-grade) form of brain tumour but have a tendency to progress to a higher grade over time – usually a number of years. As prognosis varies between individuals, patients’ clinicians are best-placed to advise how long this process may take.
Oligodendroglioma and oligoastrocytomas tumours are often classified as grade 2 gliomas.
Grade 2 astrocytomas are sometimes also referred to as diffuse astrocytomas because they infiltrate through the brain. This is due to the nature of astrocytoma cells, which reach between and around the neurons.
Grade 3 glioma (anaplastic glioma): Anaplastic means that the glioma brain tumour cells are dividing rapidly . Anaplastic gliomas, also called grade 3 gliomas, are classed as a malignant form of brain cancer. They often spread to other parts of the brain and are more challenging to treat than low-grade gliomas.
Grade 4 glioma (glioblastoma multiforme): A glioblastoma multiforme (GBM) brain tumour may have developed from a lower grade of glioma, but the name changes once it is classified as high-grade. This is to reflect the fact that a grade 4 glioma usually has a mixture of cancerous cells within it, primarily astrocytoma and oligodendroglioma cells.
You can read more about glioblastoma multiforme (GBM) tumours here.
What symptoms are associated with glioma brain tumours?
Due to the range of different types of glioma brain tumours, we recommend you visit our brain tumour symptoms page.
What is molecular testing and what do molecular markers of glioma brain tumours mean?
Current UK guidelines for the classification of gliomas defined by NICE (the National Institute for Clinical Excellence) state that tumours should also be tested for various molecular markers.
Find out more about causes of brain tumours.
How can we find a cure for gliomas?
Research we are funding across all of our Centres of Excellence will help lead towards finding a cure for glioma brain tumours.
Pioneering research at our Brain Tumour Research Centre of Excellence at Queen Mary University of London is focused on using GBM stem cells to help develop unique, patient-specific treatments.
Our team at the University of Plymouth Low-Grade Brain Tumour Centre of Excellence are researching a range of mutations in brain tumour cells that initiate tumour progression and drive growth, transforming slow-growing low-grade gliomas into high-grade gliomas. Their discoveries are designed to enable new treatments to be developed and tested in order to halt and hopefully reverse this process. The team are also testing combination therapies for low-grade brain tumours, designed to enhance the effectiveness of existing treatments.
The team of research and clinical experts at our Centre of Excellence at Imperial College, London, are part of a global collaboration looking at how the ketogenic diet can influence glioma metabolism and help in the effective treatment and management of living with this brain tumour.
Scientists at our Centre of Excellence in the University of Portsmouth are looking at mitochondria in glioblastomas, exploring ways to ‘shut down’ these ‘batteries’ that supply energy to the brain tumours.
We also fund BRAIN UK at Southampton University, the country’s only national tissue bank registry providing crucial access to brain tumour samples for researchers from all clinical neuroscience centres in the UK, effectively covering about 90% of the UK population, and an essential component in the fight to find a cure for glioma brain tumours.