Can Oligodendroglioma Be Tackled By Combined Treatments?

There are many different types of glioma, all of which are brain tumours that arise from the glial cells. However, an oligodendroglioma differs significantly in many of its characteristics from other tumours.

An oligodendroglioma takes its name from the specific cells, the oligodendrocytes, which are located in the brain and spinal cord. An oligodendroglioma normally forms in the brain.

What Is The Difference Between An Oligodendroglioma And Other Brain Tumours?

Although classed as malignant (cancerous), a particularly notable feature of them is that they are usually slow-growing grade 2 gliomas, in contrast with more aggressive forms of glioma such as astrocytomas and glioblastomas.

Some oligodendrogliomas can be grade 3, known as anaplastic oligodendroglioma, which means they are more aggressive, though still less so than glioblastomas, which are the most aggressive (grade 4) of all gliomas.

The slow-growing nature of most oligodendroglioma means the approaches to treatment will be different and the prognosis for patients is better.

However, if not treated, they will gradually have a serious effect on brain and spinal cord function as they grow and place pressure on surrounding nerves and brain tissue.

Among the symptoms that are associated with this are:

• Behavioural change
• Amnesia
• Headaches
• Loss of balance and coordination
• Speech problems
• Difficulty in thinking clearly

How Can An Oligodendroglioma Be Treated?

There are several different kinds of oligodendroglioma treatment:

• Surgery to remove as much of the tumour as possible
• Radiotherapy
• Chemotherapy
• The use of targeted therapy drugs like Vorasidenib, which works as a hormonal inhibitor designed to counteract the effects of IDH1 and IDH2 genetic mutations, which contribute to the growth of gliomas.

A key point for patients and their families to be aware of is that these treatments are not isolated alternatives, but can frequently be used in combination.

The primary means of treating an oligodendroglioma is surgery. This aims to remove (resect) all of the tumour, or as much as possible. The norm is for such surgery to be followed up by additional treatment using radiotherapy, chemotherapy or targeted therapy drugs.

In the case of radiotherapy, this is known as adjuvant radiotherapy and is designed to attack any remaining cells or tumour fragments remaining after surgery, the extent of which will usually depend on the location of the tumour and how much can safely be resected.

The effect of the radiation on any cancer is to disrupt its DNA, which can prevent cells from dividing and multiplying. This can be applied when radiotherapy is used against a whole tumour in situations when no surgery is possible, as well as post-resection.

Chemotherapy can also be used in this way and it is common for radiotherapy and chemotherapy to be combined, attacking the cancer from two different angles at the same time.

Why Might Your Oligodendroglioma Treatment Change?

However, while using a combination of different treatments can be effective in battling an oligodendroglioma, either in succession or concurrently, the multiple treatment options available also make it possible for treatments to be changed.

This may be done for two reasons:

• The treatment in use is not achieving the desired results and switching to a different method may have better results
• The side effects of some treatments may be sufficiently severe to warrant discontinuing the treatment and finding an alternative

The second instance may cover the use of experimental or therapy drugs. For example, Vorasidenib can cause liver problems, which may require a temporary or permanent cessation of its use.

What Form Of Radiotherapy Is Used To Treat An Oligodendroglioma?

When radiotherapy is used for any brain tumour, it is now the norm to utilise stereotactic radiosurgery, commonly deploying a Gamma Knife. This device, first devised in the 1960s by Swedish neuroscientist Lars Leksell, is the prime means of delivering such treatment.

It works using a very concentrated beam of gamma radiation that can target small areas with great precision. The use of increasingly advanced computer technology and 3D scanning has made this device even more precise.

As a result, the maximum dose of radiation can be delivered to the tumour, section of tumour or remaining cells following resection to produce the maximum effect in disrupting the DNA of the cancer, while minimising radiation exposure for surrounding healthy tissue.

The latter is a priority whenever radiotherapy is used, but more so when it is the brain or another sensitive organ that lies adjacent to the area where the radiation is being delivered.

Our approach to care is always that of treating each patient as an individual and that means there is never any one set approach to treating an oligodendroglioma.

In addition to the circumstances of each patient, there will be a focus on collaboration and consent, keeping every patient informed about what is being done and why, not least when changes are made to treatments to seek better outcomes.

Learn more about our advanced radiotherapy and neurosurgical treatments for oligodendroglioma on the Queen Square website.