How long can you have glioblastoma before experiencing symptoms?

A GLIOBLASTOMA is the most common high grade primary brain tumour in adults.

It's a devastating diagnosis, with more than 2,000 people being diagnosed with the aggressive tumour each year in the UK, according to University College London.

It is an aggressive form of cancer, and it's rare for someone diagnosed to survive beyond five years.

Knowing the symptoms of the disease may help get an earlier diagnosis.

What is glioblastoma?

Glioblastomas are grade 4 brain tumours and are sometimes called glioblastoma multiforme, the NHS states.

It is a type of glioma, one of the most common types of primary brain tumours -  making up around a third.

The cancer begins in the brain and almost never spreads to other parts of the body. However, it's complexity makes it difficult to treat.

It is also resistant to treatment, as the cells within the tumour are not all of the same type.

There are no known causes of glioblastoma, as is the case with most brain tumours, therefore, there is no clear way to prevent the disease.

The first line of treatment is surgery to try and cut the tumour out. However, because glioblastomas "diffuse", meaning they invade healthy cells around them, it's very difficult to remove the tumour without harming healthy parts of the brain.

Chemotherapy and radiation therapy can be helpful to stop the tumour cells growing and spreading. But despite the high intensity of the treatment, the cancer usually recurs.

How long can you have glioblastoma before experiencing symptoms

Glioblastomas are very fast growing. Once found, experts can see them double within seven weeks.

But, according to Dr Stephen Bagley, assistant professor of medicine at , the first spark of glioblastoma in the brain remains something of a mystery to medical experts.

One concluded that a glioblastoma starts growing 330 days on average - almost a year - before a diagnosis.