Oligodendroglioma

Symptoms can depend on the size and position of the tumour. They also depend on how slowly or quickly it grows. Symptoms may develop suddenly, or slowly over months or even years.

Symptoms may happen if a tumour presses on or grows into nearby areas of the brain. This can stop that part of the brain from working normally. Symptoms can also happen because the tumour causes a build-up of pressure inside the skull. This is called raised intracranial pressure.

Possible symptoms include:

• seizures (fits)
• headaches
• feeling or being sick
• difficulty speaking or understanding words
• weakness in an arm or a leg
• problems with movement and balance
• problems with sight.

Seizures are often the first symptom. People with a slow-growing oligodendroglioma may have mild symptoms for several years before the tumour is found.

We have more information about possible symptoms of a brain tumour.

Your doctors need to find out as much as possible about the type, position and size of the tumour so they can plan your treatment.

You will usually have brain scans to find out the exact position and size of the tumour.

You may first have a brain CT scan first. You also usually have an MRI brain scan.

Having an MRI scan is important as it can give more detailed information. If you are not able to have an MRI scan, your doctor will discuss this with you.

There are different types of MRI scans. You may need to have more than 1 to ensure that your doctors have all of the information they need to make a diagnosis and guide any treatment.

We have more information on the different types of MRI scans used to diagnose brain tumours.

You may also have a biopsy, which involves an operation to take a sample of the tumour to test. Brain tumour biopsies are usually done at the same time as surgery to remove the tumour.

Your doctor may also:

• do a physical examination of parts of your nervous system, such as checking your reflexes and the power and feeling in your arms and legs
• shine a light at the back of your eye to check if there is swelling
• ask you questions to check your reasoning and memory
• arrange for you to have blood tests to check your general health and to see how well your kidneys and liver are working.

A neuro-pathologist (doctor who specialises in examining brain tissue samples) looks at the tumour sample under a microscope. This is to find out how fast the tumour is likely to grow. Tests called molecular marker tests are also done on the sample to look for genetic changes (mutations) in the tumour cells. Molecular markers may also be called biomarkers.

Your doctor will use information to understand how quickly a tumour might grow and to help them decide on treatment.

The main treatments for oligodendrogliomas are surgery, radiotherapy and chemotherapy. You may have a combination of treatments.

Treatment depends on:

• the size and position of the tumour
• its grade
• the molecular marker results
• your symptoms.

A team of specialists will plan your treatment. Your specialist doctor and specialist nurse will explain the aims of your treatment and what it involves. They will talk to you about the benefits and risks of different treatment types. They will also explain the side effects.

You may be given a choice of treatment options. You will have time to talk about this with your family, friends and your hospital team before you make any treatment decisions.

You will need to give permission (consent) for the hospital staff to give you the treatment. Ask any questions about anything you do not understand or feel worried about. Tell your specialist if you need more information or more time to decide on a treatment.

If you need treatment, you usually have surgery to remove the tumour. The surgeon will remove as much of the tumour as safely as possible.

Depending on the size and position of the tumour, sometimes it may not be possible to remove all the tumour. Your surgeon will discuss this with you and whether you might need further treatment after surgery.

If surgery is not possible, your doctor will talk to you about other treatments. 

After surgery, the MDT (multidisciplinary team) will discuss whether further treatment might be recommended. This may be radiotherapy or chemotherapy, or both. You may be referred to a doctor who specialises in cancer treatment called an oncologist. They will talk to you about the benefits and possible side effects of the treatment.

Further treatment will depend on:

• how much of the tumour it was possible to remove
• the grade of the tumour
• the molecular markers
• your symptoms
• your general health.

The aim of further treatment is to delay or reduce the risk of the oligodendroglioma coming back after surgery. It also aims to delay or reduce the risk of low-grade tumour developing into a higher-grade tumour (malignant or cancerous transformation).

If diagnostic brain scans suggest the tumour is low-grade and not causing you problems, your doctor may suggest active monitoring. This is also called active surveillance or watch and wait. Active monitoring means regularly checking the tumour with follow-up MRI brain scans to find out if it is growing or changing. Your doctor will also monitor your symptoms carefully.

Some people may have active monitoring before they have any treatment. This means you have active monitoring instead of having treatment straight away.

They may also suggest having a biopsy to confirm the diagnosis, if you have not had one already. A biopsy is an operation to remove a small piece of the tumour.

If you have surgery, active monitoring may also be suggested after surgery instead of having immediate further treatment. This means delaying treatment until it is needed.

Delaying treatment might be beneficial in some situations, because treatment can cause side effects. Some of these may be permanent. Instead of starting treatment straight away, you may meet your specialist doctor regularly to discuss the results of your scans. The scan results help your doctor know if and when to recommend treatment.

High-grade tumours grow more quickly, so will usually need to be treated straight away.

You may be offered  active monitoring after surgery. This will depend on:

• the grade of the tumour
• molecular markers
• how much was removed with surgery
• your age.

You have regular scans to check if the tumour is growing again and delay having further treatment until it is needed.

You may find it difficult to cope with the uncertainty of active monitoring and not having treatment. Your specialist nurse can give you support and advice on coping. You might find it helpful to talk about how you feel with family and friends. Or you may want to talk to people who are in a similar situation. You could try joining a support group or you could visit our brain cancer forum to talk with people who have been affected by brain tumours, share your experience, and ask an expert your questions.

After surgery, the MDT will discuss whether further immediate treatment might be recommended. This may be radiotherapy, chemotherapy, or both. You may also have radiotherapy and chemotherapy if surgery is not possible, or if the tumour cannot be completely removed.

You may be referred to a doctor who specialises in cancer treatment called an oncologist. They will talk to you about the benefits and possible side effects of the treatment.

Radiotherapy uses high-energy x-rays to control or destroy the tumour cells.

Chemotherapy uses anti-cancer drugs to destroy the tumour cells. If you have chemotherapy, a combination of drugs may be used. The chemotherapy drugs most commonly used are:

• procarbazine
• lomustine (CCNU)
• vincristine.

This combination is called PCV.

Your doctor will talk to you about your treatment options.

Your cancer doctor or specialist nurse will explain your treatment and possible side effects. Most side effects are short term and will improve gradually when the treatment is over. Some treatments can cause side effects that can continue and may not get better. These are called long-term effects. You may also get side effects that start months or years later. These are called late effects.

We have more information about coping:

• before and after surgery
• with side effects of radiotherapy
• with side effects of chemotherapy

You may need treatment for the symptoms of an oligodendroglioma before you have any treatment for the tumour. You may also need your symptoms managed during your main treatment after it has finished.

You may have the following treatments:

• Drugs to reduce the risk of having seizures called anti-convulsants or anti-epileptic drugs (AEDs).
• Steroids to reduce swelling around the tumour.
• Surgery to drain off excess fluid, to reduce pressure inside the skull.

Sometimes a brain tumour cannot be removed or may stop responding to treatment. If this happens, you can still have treatment for any symptoms. You will have supportive care (sometimes called palliative care) from a specialist doctor or nurse who is an expert at managing symptoms and providing emotional support.

We have more information about coping with advanced cancer.

Clinical trials are a type of medical research involving people. They are important because they show which treatments are most effective and safe. This helps healthcare teams plan the best treatment for the people they care for.

Trials may test how effective a new treatment is compared to the current treatment used. Or they may get information about the safety and side effects of treatments.

They will give you information about the clinical trial so that you understand what it means to take part. If you decide not to take part in a trial, your specialist doctor and nurse will respect your decision. You do not have to give a reason for not taking part. Your decision will not change your care. Your doctor will give you the standard treatment for the type of tumour you have.

Clinical trials also research other areas. These include diagnosis and managing side effects or symptoms. As these tumours are rare, there may not always be a relevant clinical trial happening. If there is, your doctor or nurse may ask you to think about taking part.

We have more information about clinical trials.