What is a glioma?
Primary brain tumours are called gliomas. They are tumours of brain cells and they are classified according to the type of cell giving rise to the tumour. Currently, the classification of gliomas also takes into account the genetic profile, which helps to predict behaviour and response to treatments.
Risk factors for gliomas include:
Age: gliomas are more common between ages 45 and 65 years old
Exposure to radiations, including radiations used to treat other forms of cancer
Electromagnetic radiations do not cause gliomas. In fact, the use of cellphones is not associated to increased risk of glioma.
Based on the histological features, gliomas are classified into 4 grades:
Grade I: benign gliomas, including pilocytic astrocytoma. Benign gliomas are rare and are the only type of glioma curable with surgery.
Grade II: diffuse low grade gliomas. Grade II gliomas tend to grow slowly and progress into cancer several years after their diagnosis.
Grade III: anaplastic gliomas. These gliomas grow faster and behave more aggressively.
Grade IV: this type of glioma is also known as glioblastoma and this is the most malignant of all brain tumours.
Astrocytomas, anaplastic astrocytomas and glioblastomas
Ependymomas, anaplastic ependymomas, myxopapillary ependymomas and subependymomas
Oligodendrogliomas and anaplastic oligodendrogliomas
When is a brain tumour suspected?
Gliomas can affect the brain functions and rarely can cause life-threatening risks depending on the location, size and grade.
Gliomas can be asymptomatic, but when they enlarge they may present with:
New seizures or fits
Rarely, symptoms from raised intracranial pressure such as severe headache, nausea and vomiting
An incidental finding on a brain scan done for another reason
What investigations will I need?
If your GP suspects a brain tumour, you will be referred to a Consultant Neurosurgeon specialized in the management of brain tumours.
Tests carried out for suspected gliomas include:
Brain MRI scan or alternatively with a brain CT scan if you a medical condition contraindicating an MRI.
In some cases, special physiological MRI or CT scans using cerebral perfusion or spectroscopy techniques, tractography and functional MRI are also carried out.
This will be discussed with you in detail on an individual basis.
If you are having surgery, then a further image-guidance MRI scan may need to be performed.
How is a glioma treated?
Often at diagnosis, steroids in the form of dexamethasone tablets can be started to reduce brain swelling. Brain swelling or oedema often occurs in normal brain adjacent to a tumour.
If you have presented with a seizure then you will also be started on anti-seizure medication called anti-convulsants.
Your case will be discussed in the Neurooncology Multidisciplinary Team Meeting. The team comprises neurosurgeons, oncologists, psychologists, radiologists, pathologists and nurse specialists.
Gliomas from grade II to grade IV cannot be cured, but their natural course and life expectancy can be significantly modified if treated.
Gliomas are in most cases treated with surgery. However, in view of the fact that gliomas tend to send microscopic extensions into surrounding normal brain tissue, radical resection is not always possible and surgery can be followed by chemotherapy and radiotherapy.
Surgery for glioma
Surgical options for gliomas include maximal safe resection and biopsy.
Currently, most patients diagnosed with a glioma undergo surgical resection as this has been proven to be the most effective way to control this condition.
To remove gliomas, a craniotomy is required. However, your hair will not be shaved and no dressing or head bandages are usually required.
Surgery for gliomas is performed preferably awake or alternatively under general anaesthesia. Currently, new techniques are also employed to improve outcomes and these include minimally invasive techniques, fluorescence-guided resection, Neuro-navigation, intraoperative ultrasounds and intraoperative Neurophysiology mapping and monitoring.
Surgery aims to remove as much of the tumour as safely as possible. During surgery, samples of the tumour will be collected and sent to the Neuropathology lab were the tumour will be analysed in detail to establish the exact diagnosis.
The risks of surgery for glioma will be discussed with you in detail on an individual basis.
What happens after surgery?
After surgery you will receive pain relief for headache and you will be mobilised within a few hours. Most patients are able to go home on day 3 or 4. If you require rehabilitation, a team of specialized therapists will help you recovering from surgery.
You will have sutures or staples in the wound, which will be removed by your local district nurse service.
Seven to ten days after surgery, you will have a follow-up consultation to discuss the pathology results.
Your Brain & Spine Clinic neurosurgeon will discuss this with you in detail.
Do I need radiotherapy and chemotherapy?
Gliomas can require multi-modal treatment and it is likely that you will be reviewed by one of our Neuro-oncologists.
Oncology treatments after surgery include radiotherapy, chemotherapy tablets or a combination of both.
Throughout your treatment you will have a named specialist nurse, be given written information and have plenty of opportunity to discuss your treatment in detail with your surgeon and oncologist.