Astrocytoma

What are astrocytomas?

Astrocytomas develop from a type of glial cell called astrocytes. Astrocytes are star shaped cells. They support the nerve cells (neurones) in the brain.

Read about glial cells and the different parts of the brain

Doctors use a system to group (classify) brain tumours into different groups (categories) and types. The World Health Organisation (WHO) regularly update this system. The information in this page is based on the WHO classification of 2021.

Astrocytomas are a type of brain tumour that belongs to a group of brain tumours called gliomas.

Doctors have changed the way they group and describe astrocytomas. They are now called:

• astrocytoma, IDH mutant

What does IDH mutant mean?

Your doctor looks to see if there are certain gene changes in the brain tumour cells. These tests are also called biomarker or molecular studies. The results help your doctor find out what type of glioma you have.

IDH (isocitrate dehydrogenase) is a gene. Your doctor looks for changes (mutations) in the IDH gene.

Your doctor diagnoses:

• astrocytoma, IDH mutant - if you have changes (mutations) in the IDH gene

• glioblastoma, IDH wildtype - if you don’t have changes in the IDH gene. The term ‘wildtype’ describes an unchanged gene.

This page is about astrocytoma, IDH mutant.

Read about glioblastoma

Diffuse and circumscribed astrocytomas

Some astrocytomas are very localised (focal). This means it is easy to see the border between the tumour and the normal brain tissue on a scan or during surgery. Doctors call these circumscribed astrocytomas. These are more common in children.

Other astrocytomas are called diffuse astrocytomas. They don’t have a clear boundary between the tumour and the normal brain tissue.

Grades of astrocytomas

Astrocytomas are put into groups according to how quickly they are likely to grow. These are called grades. 

The grade depends on how the cells look. Generally, the more normal the cells look, the lower the grade. The more abnormal the cells look, the higher the grade. Grade also depends on genes and proteins in the tumour cells. 

There are 3 grades of IDH mutated astrocytomas:

• grade 2

• grade 3

• grade 4

Grade 1 astrocytoma

Some astrocytomas are grade 1 tumours. One example is a pilocytic astrocytoma. This is a slow growing tumour that is most often diagnosed in children and young adults. Rarely, it can also develop in older adults. Surgery is usually the main treatment.

Find out more about grades of brain tumours

Symptoms of astrocytoma

The symptoms depend on where the tumour is in the brain. They can include:

• headaches

• seizures (fits)

• weakness or numbness in your arms and legs

• problems with your eyesight such as blurred vision

• changes in your personality

• problems with balance and general movement

What tests will I have?

You have tests to diagnose an astrocytoma. Your doctor checks the size of the tumour and its location. This helps your doctor plan your treatment. The tests you might have include:

• MRI scan or CT scan

• a test of your neurological system (neurological examination)

• a biopsy

We have more information about the tests you might have to diagnose a brain tumour

Treatment

The main treatments for astrocytoma are:

• surgery

• radiotherapy, which uses high energy x-rays to destroy cancer cells

• chemotherapy, which uses cytotoxic drugs to destroy cancer cells

Your treatment depends on the grade of your astrocytoma. It also depends on whether you have changes (mutations) in certain genes.

Follow up

You have regular appointments with your doctor or nurse after treatment finishes. Your doctor examines you at each appointment. They ask how you are feeling, whether you have had any symptoms or side effects, and if you are worried about anything. You might also have MRI scans on some visits.

How often you have check ups depend on your individual situation.

You might have an MRI scan every 3 to 6 months, for two years. You then have an MRI scan every 6 months or every year.

Read more about follow up appointments after treatment for a brain tumour

Coping with astrocytoma

Coping with a diagnosis of a brain tumour can be difficult, both practically and emotionally. It can be especially difficult when you have a high grade tumour. Being well informed about the type of tumour you have, and its treatment can make it easier to cope.  

Find out what you can do, who can help and how to cope with a brain tumour