Oligodendrogliomas are primary brain tumours which means they have originated in the brain instead of spreading from elsewhere. They belong to the group of brain tumours known as gliomas as they develop from a type of glial cell known as an oligodendrocyte.
Oligodendrogliomas are the third most common glioma, accounting for 2-5% of all primary brain tumours and 5-18% of gliomas. They are more common in adults, particularly in people aged 40-60.
Oligodendrocyte cells produce a fatty, protective covering (called myelin) of the nerve cells in the brain, which helps nerve signals to travel along the nerves more quickly.
Oligodendrogliomas are divided into two grades:
The majority of oligodendrogliomas occur in the frontal lobe, and the second most common site affected is the temporal lobe.
Grade 3 oligodendrogliomas are more common in older people aged 60-80, but can affect any age. Oligodendrogliomas are slightly more common in men than in women.
Occasionally oligodendrogliomas contain clear evidence of different glial cells called astrocytes. These tumours which have a mix of cells may be referred to as 'oligoastrocytomas'. However, this diagnosis is discouraged because genetic testing can now determine whether the tumour should be classified as an astrocytoma or an oligodendroglioma. To find out more about genetic testing see our biomarkers webpage.
A person with an oligodendroglioma may display one or more of these symptoms:
Sometimes the symptoms experienced depend on where the brain tumours are located. If they are in the frontal lobe this may cause gradual changes in mood and personality, weakness or numbness in muscles of one side of the body.
If it is located in the temporal lobe, this may cause problems with speech and coordination or it may affect memory.
The treatment of an oligodendroglioma depends on whether a tumour is grade 2 or grade 3.
Some grade 2 oligodendrogliomas grow very slowly and you may be put on 'watch and wait' which involves close monitoring of your tumour using MRI scans.
If the tumour is large or causing symptoms, surgery may be performed to remove as much as possible if it is located in an area where it is safe to remove. If the neurosurgeon manages to remove all of the visible tumour cells, this may be the only treatment you receive and you might then be put on 'watch and wait'. If the tumour appears to have changed or grown, this is when your doctors will consider additional surgery or starting treatment with radiotherapy or chemotherapy. Many patients with a grade 2 oligodendroglioma will remain in remission (i.e. no signs of the tumour growing) for several years after surgery.
Like grade 2, grade 3 oligodendrogliomas are usually first treated with surgery. If the tumour is located in an area where it is safe to remove, the neurosurgeon will attempt to remove as much as possible. Oligodendrogliomas are often 'diffuse' meaning they have threadlike tendrils that extend into parts of the brain making it difficult to remove completely. After surgery patients will often receive a combination of radiotherapy and chemotherapy.
Effectiveness of treatment
The use of chemotherapy is particularly successful as a treatment when it is administered to patients whose tumours contain a particular gene change called the 1p and 19q chromosomal deletions. People whose tumour cells have this gene change respond well to PCV chemotherapy and detecting this genetic alteration with a test is now essential when evaluating what treatment is used for people with these tumours. Please see our biomarkers page for more information
As with most tumours, the cause is not known. This can be a difficult thing to accept and can leave you feeling helpless, but there is nothing you could have done to prevent this from happening.
The Brain Tumour Charity is contributing to the funding of research into a possible cause that is focussed around our genes.
Prognosis in relation to brain tumours is an average number, given in months or years that a patient is likely to survive for, following diagnosis. While this number can give a general overview of prognosis for oligodendrogliomas, it is important to remember each person's journey is unique and not necessarily represented by an average figure. This statistic does not take into account individual circumstances such as your general health and quality of care provided by their hospital or treatment centre.
Information about prognosis can be difficult to receive – some people do not want to know, whilst others do. There is no wrong or right answer as to whether or when to receive such information. If you would like to find out more information, please visit our prognosis page.
Page last reviewed: 07/2016
Next review date: 07/2019
If you have further questions, need to clarify any of the information on this page, or want to find out more about research and clinical trials, please contact our team:
0808 800 0004 (free from landlines and mobiles)
01252 749 999
Phone lines open Mon-Fri, 09:00-17:00
You can also join our active online community on Facebook - find out more about our groups.