Brain Tumour Information

• Brain tumours are defined as the collection or mass of abnormally growing cells inside the brain. 
• Your skull is very rigid to protect the brain. 
• The next layers within the skull are collectively known as the meninges. The first and toughest of these is called the dura mater – this is a thick layer of connective tissue that encases the brain, spinal cord and spinal nerves. 
• The next layer is known as the arachnoid, a much more delicate layer that follows the creases of the brain and spinal nervous tissues.
  - The cells of the brain are delicately encased in a blood brain barrier. This barrier is designed to keep things out such as microbes and toxins. The blood brain barrier is also very good at keeping out chemotherapies and other treatments.
• Any growth within a restricted place can cause issues.
• Brain tumours may be referred to as cancerous (malignant) or non-cancerous (benign). This “black and white” so called fact is an oversimplification of a complex scenario where there are “shades of grey” between malignant and benign labels that  are very important with respect to treatment and ultimately prognosis
• Both malignant and benign tumour growth can put pressure on the brain. This pressure can cause brain damage and be life threatening.
• The most common initial form of treatment for both malignant and benign tumours is surgery.
• The main aim of surgery is to biopsy the tumour, remove as much as possible without causing a permanent brain injury, then look at all options regarding all methods of controlling tumour growth such as radiotherapy/chemo/immune therapy.

Primary brain tumours originate in your brain. They can develop from your:

• brain cells
• the membranes that surround your brain, the meninges
• nerve cells and the cells that surround them (known as glial cells)
• Pituitary gland

In adults, the most common types of brain tumours are gliomas and meningiomas.

The symptoms of a Brain Tumour widely vary from being very subtle (such as forgetfulness, change in moods, migraines) to very drastic (such as seizures).

This is not an exhaustive list of symptoms, however they are the most common:

• nausea
• headache
• vomiting
• seizure
• dizziness
• weakness of the arm, leg or both
• double vision
• speech problems
• behavioural changes

These symptoms can vary from person to person depending upon:

• location in the brain
• size of the tumour
• rate of tumour growth

For the majority of brain tumours, the honest answer here is that we simply don’t know. There are numerous large population studies conducted world-wide (called epidemiology studies) to identify cause.

We do, however know that some brain tumours are caused by genetic and environmental reasons:

• Family History (although very rare in just 5-10% of cases)
• Age: Brain tumour incidence increases with older age
• Race: Brain tumours are more common in Caucasians
• Exposure to Radiation: People who have been exposed to ionizing radiation have an increased risk of brain tumours
• Exposure to Chemicals.

Depending on the symptoms, people most commonly present to their General Practitioner (GP) or the Emergency Department (ED). The treating doctor will perform a comprehensive examination to work out exactly what is going on. They may assess:

• Vision 
• Speech 
• Reflexes
• Muscle strength
• Sensation
• Co-ordination

But the definitive test is to try and visualise what is happening in the brain. 

• CT Scan
• MRI (higher resolution than CT)

A CT scan is often the first diagnostic test ordered if a brain problem is suspected as they are cheap and readily available. A dye (contrast) can be injected to better define what is happening in the brain (blood vessels). 

An MRI is typically performed if the CT shows an abnormality. MRI scans generally provide a more detailed picture of the brain and its structures. Again, contrast can be added to a MRI scan to increase clarity.

As mentioned, abnormal growth in the brain puts immense pressure on the rest of the healthy brain. So most patients first undergo safe, maximal surgery. This may be a biopsy or resection/removal of the tumour depending on the risk /reward of operating in the part of the brain affected by the tumour.

Some brain tumours are best treated by other methods rather than surgery eg lymphoma/germinoma/certain glioma subtypes so the neurosurgeon has to weigh up the risk of surgery in regards to other methods that might be more optimal in the treatment of that particular tumour type. 

There are several types of surgeries that will be recommended by your neurosurgeon based on the location of the tumour and the size of the tumour. Safety is paramount and the goal is to remove as much of the tumour as possible but to ensure the rest of the brain suffers no trauma.

Yes, the plastic face mask, or immobilisation mask, is designed to keep your head still and to make certain that the radiation is directed to the same area during each session. Its made especially for you and fixed to the table.

The mask is made of a tight-fitting mesh, but you will wear it for only about 10 minutes at a time. You can see and breathe through the mask, but it may feel strange at first. Let the radiation therapist know if wearing the mask makes you feel anxious, as this can be managed with medicines.

Unfortunately there are side effects that generally occur in the treatment area. These side effects can be temporary, but some may last for a few months or years, or be permanent.

The main side effects experienced by patients include: 

• nausea – often occurs several hours after treatment
• headaches – often occur during the course of treatment
• tiredness or fatigue – worse at the end of treatment; can continue to build after treatment, but usually improves over a month or so
• dry, itchy, red, sore or flaky skin – may occur in the treatment area, usually happens at the end of treatment and lasts one to two weeks before going away
• hair loss – may occur in the brain tumour treatment area and may be permanent
• dulled hearing – may occur if fluid builds up in the middle ear and may be permanent.

If you experience any of these side effects, talk to your radiation oncology team.

A small number of adults who have had radiation therapy to the brain have side effects that appear months or years after treatment. These are called late effects and can include symptoms such as poor memory, confusion and headaches. The problems that might develop depend on the part of the brain that was treated.

High-dose radiation to the pituitary gland can cause it to produce too much or too little of particular hormones. This can affect body temperature, growth, sleep, weight and appetite. The hormone levels in your pituitary gland will be monitored during treatment.

Unfortunately, brain tumours as well as their treatments can cause swelling in the brain and leads to complications. Steroids, typically dexamethasone, is given to relieve and reduce this swelling, and can be given before, during and after surgery, radiation therapy and chemotherapy.  There are a number of side effects of steroids so your doctors will try and minimise the dose and time on these medications.

There is no clinical evidence to support extreme diets and reducing brain tumour growth. A ketogenic diet is often mentioned in the press. Ketogenic diets are very low carbohydrate diets, usually with restricted protein, but with very high levels of fat. It‘s a very complicated diet to follow and can cause unpleasant side-effects, such as sickness, tiredness and constipation. 

We suggest involving a dietician in your treatment team as a balanced diet and healthy eating is important. Some treatments may also turn you off certain food groups so its good to identify this.

There is no evidence that exercise can prolong survival, however mental wellbeing is critically important after the diagnosis of a brain tumour. 

Exercise gets the endorphins in your body flowing and is well regarded by many clinicians. Endorphins are the “happy” hormones that can definitely help with mental illness and depression which are common in brain tumour patients. Make exercise fun!

Keeping generally fit and healthy will help your body in a number of ways not directly related to your brain tumour, so as always you should exercise as much as you can.

Biomarkers are particular tests performed on tumours that help characterise them further. This will help your doctors guide their treatment, and to manage your expectations of what the tumour may mean for you.

IDH is a common gene involved in general respiration of your cells. The mutation results in a loss of normal enzymatic function and the abnormal production of 2-hydroxyglutarate (2-HG). Prognostically, IDH mutations are one of the strongest prognostic markers in low-grade gliomas, but also high-grade gliomas. The majority of low-grade diffuse gliomas (astrocytomas and oligodendrogliomas) are IDH-mutant. To test for IDH1 mutations, DNA from some of your tumour (stored in pathology at the time of your surgery) is extracted and sequenced. There is also a very simple immunohistochemistry (IHC) test that can detect IDH1 mutations in your tumour. The presence of an IDH1 mutation is a favourable prognostic marker, that is it means growth of the tumour is less aggressive. Importantly, treatments to directly target this molecular aberration are being developed and tested. IDH 2 mutations(another favourable marker) require DNA sequencing as there is no simple IHC test

Alterations in chromosomes within tumours are common. In particular, complete deletion of both the short arm of chromosome 1 (1p) and the long arm of chromosome 19 (19q) (1p/19q co-deletion) is the molecular genetic signature of oligodendrogliomas. This molecular event is thought to confer better response to chemotherapy.

Another common change in tumours is called methylation. This is wear modification of part of the genetic material in the tumour cells results in the protein that gene codes for not being produced. This can be either good or bad depending on the exact gene involved.

Methylation of the methylguanine methyltransferase (MGMT) gene is suggested to confer better response for people diagnosed with GBM when treated with alkylating chemotherapies such as Temozolomide (TMZ). MGMT methylation is a specialised test that is often requested by your treating oncologist to guide their therapy decisions at the time of tumour recurrence.

Diffuse intrinsic pontine gliomas (DIPG) or Diffuse Midline Gliomas are highly aggressive and difficult to treat brain tumours found at the base of the brain. They are glial tumours, meaning they arise from the brain's glial tissue — tissue made up of cells that help support and protect the brain's neurons. These tumours are found in an area of the brainstem (the lowest, stem-like part of the brain) called the pons, which controls many of the body’s most vital functions such as breathing, blood pressure, and heart rate.

Diffuse intrinsic pontine gliomas account for 10 percent of all childhood central nervous system tumours. DIPGs are usually diagnosed when children are between the ages of 5 and 9, they can occur at any age in childhood. These tumours occur in boys and girls equally and do not generally appear in adults.

Choroid plexus tumours arise from a structure in the brain called the choroid plexus. It lines the ventricles (fluid-filled cavities) of the brain and its primary function is to produce cerebrospinal fluid (CSF). Choroid plexus tumours almost always form within the ventricles. They can also form in other regions of the CNS. There are three Grades of Choroid Plexus tumours (Grade I-III). Grade I Choroid Plexus Papilloma are low grade and grow very slowly. Grade II atypical Choroid Plexus Papilloma tumours are of mid-grade and have a higher chance of growing back after being surgically removed. Grade III Choroid Plexus tumours are aggressive and invasive and are defined as malignant.

Surgery is the first line of treatment to safely remove as much tumour as possible. Depending on the Grade, Radiation Therapy and Chemotherapy may be given.

A meningioma is a tumour that arises from the meninges — the membranes that surround your brain and spinal cord. Although not technically a brain tumour, it is included in this category because it may compress or squeeze the adjacent brain, nerves and vessels. Meningioma is the most common type of tumour that forms in the head. Most meningiomas grow very slowly, often over many years without causing symptoms. But sometimes, their effects on nearby brain tissue, nerves or vessels may cause serious disability. Meningiomas occur more commonly in women and are often discovered at older ages, but may occur at any age. Because most meningiomas grow slowly, often without any significant signs and symptoms, they do not always require immediate treatment and may be monitored over time.

There are three grades of Meningioma (I-III):

1. WHO Grade I meningiomas are low grade tumours and are the most common. This means the tumour cells grow slowly.
2. WHO Grade II atypical meningiomas are mid-grade tumours. This means the tumours have a higher chance of coming back after being removed. The subtypes include choroid and clear cell meningioma.

WHO Grade III anaplastic meningiomas are malignant (cancerous). This means they are fast-growing tumours. The subtypes include papillary and rhabdoid meningioma.

Treatment of meningiomas depends predominantly on their location, size  and their rate of growth.

Surgery is the commonest treatment for meningioma, as completely removing the tumour is often curative.  Meningiomas range from being very safe to remove to very risky. Some meningiomas that are in risky locations may be treated initially with radiation therapy.

Radiation may be used in addition to surgery, particularly in many Grade II meningiomas and almost all Grade III meningiomas.

Craniopharyngioma is a rare type of noncancerous (benign) brain tumour. Craniopharyngioma begins near the brain's pituitary gland, which secretes hormones that control many body functions. As a craniopharyngioma slowly grows, it can affect the function of the pituitary gland and other nearby structures in the brain. Craniopharyngioma can occur at any age, but it occurs most often in children and older adults. Symptoms include gradual changes in vision, fatigue, excessive urination and headaches. Children with craniopharyngioma may grow slowly and may be smaller than expected.