How Are The Different Grades Of Oligodendroglioma Treated?

A complex aspect of treating brain tumours through neurosurgery or radiotherapy is that treatments need to be adaptable to the varying stages and locations of tumours within the brain. An illustration of the variability of treatment can be seen in oligodendroglioma, a rare type of brain tumour that affects cells in the brain that produce nerve-protecting myelin sheaths. Because of this, there are various locations where the glioma can develop and various grades of aggressiveness that they are categorised under. All of these different factors can have a significant effect on which treatments are available from specialist neurosurgeons. To understand why, it is important to understand the grading system for brain tumours, how oligodendrogliomas can vary, and what treatments and support are available.

Why Are Brain Tumours Graded?

Similar to how other cancers are defined in terms of stages, brain tumours are graded based on the nature of the tumour’s cells and how likely they are to grow and for the condition to progress. Following a biopsy and other tests you may have on the tumour itself, a pathologist will assign a grade based on the behaviour of the cells. There are four main grades, themselves divided into low-grade and high-grade tumours. Low-grade tumours are generally categorised as being benign, whilst high-grade tumours are usually described as being malignant. The first two grades are typically non-cancerous whilst the latter two are cancerous. The four grades are as follows:

• Grade 1 - At this grade, the tumour cells mostly resemble normal brain cells, and the tumour itself will grow very slowly and be unlikely to spread.
• Grade 2 - Whilst still slow growing, they can spread to nearby tissue, and are starting to look more abnormal under a microscope.
• Grade 3 - The cells are cancerous and there is a greater risk of them spreading beyond the brain to the spinal cord.
• Grade 4 - These tumours are fast-moving, are more likely to spread and typically require more intensive treatment to stop them growing back.

Most brain tumours can be graded using this scale, but there are some cases where it can be somewhat more complex. Some benign tumours, for example, can put pressure on a part of the brain that can have more serious complications, whilst others can progress from one grade to another. Oligodendroglioma tumours are either grade 2 (or diffuse) or grade 3 (anaplastic), and each will be treated differently based on this, as well as their size and location.

What Are The Treatment Options For Diffuse Oligodendroglioma?

Irrespective of the grade of tumour, oligodendroglioma responds well to treatment, and there will typically be a range of options available when it comes to the right treatment for you. Diffuse oligodendroglioma, as a low-grade glioma, tends to grow slowly, and both the symptoms and the treatment plan can vary depending on its location. The most common symptom is seizures, particularly if you have no previous history of them, but balance issues, persistent or recurring headaches with no other cause, changes in behaviour or cognition, and a loss of feeling in your arms and legs can all be signs of an oligodendroglioma. These symptoms will depend on the tumour’s location, with frontal lobe cases typically causing muscle weakness and personality changes, whilst temporal lobe ones can affect memory, speech and general coordination. This, alongside any tests, will shape the treatment of a grade 2 oligodendroglioma. There may be a period of active monitoring if immediate treatment is not required, to ensure that it is not having any effects on your quality of life. If it is, or it is large enough that it could start causing issues, then the primary treatment path is neurosurgery to excise the tumour, followed by a course of targeted radiotherapy or chemotherapy to ensure that any remaining tumour cells are destroyed before they can grow back.

What Are The Treatment Options For Anaplastic Oligodendroglioma?

The primary difference between the treatment of grade 2 and grade 3 oligodendroglioma cases is that treatment will begin immediately and will tend to be more immediate and aggressive in order to remove any trace of the tumour before it can grow and spread further. This typically involves surgery to remove the tumour, followed by a combination chemoradiotherapy course to ensure that the cancerous cells are destroyed completely and remove the risk of it coming back. If it does come back, a further course of chemotherapy, radiotherapy or additional surgery is possible as a follow up treatment. Visit the Queen Square website to discover how our advanced neurosurgical treatments can help treat oligodendroglioma and other conditions.