Jesse Tristram, 26, from Leyton, east London, learned he had a brain tumor when an automated message exposed the game.

“Within two to three weeks, I went from waking up completely fit and healthy to feeling a little weird and fighting an often-deadly cancer.”

He says his symptoms were unclear at first, with one of the first symptoms being “an intense deja vu” and he attributes it to stress or lack of sleep.

But after cycling to the local swimming hole, he felt a hallucinatory flash, a “terrible, disgusting” taste in his mouth and an overwhelming sense of dread.

“I felt like whatever this was was the worst thing that had ever happened to me in my entire life.”

He knew it “wasn’t real” because his hallucination featured a celebrity he had never met, so he continued swimming.

However, Jesse experienced further events on his way home and later that day into the night.

He rang the out-of-hours GP and was told he was having some sort of seizure. In the following days, he was referred to have a magnetic resonance imaging (MRI) scan.

After two scans he was told to go to A&E. A lesion was detected in his brain.

He said he was reassured there was nothing to worry about and that “people his age don’t get this type of cancer.”

He was given a phone number to call and the answering machine gave him that information.

“It said, ‘Welcome to the Brain Tumor Unit,’ so that’s how I found out.”

He says he and his partner “started laughing” when they realized this, probably out of shock.

Although it was initially thought to be “low grade,” Jesse says within five weeks of being diagnosed it was discovered that his tumor had doubled in size.

The NHS, the diagnosis and treatment guide, describes the cancer pathway as a “cancer maze”, with some of her symptoms being ignored and her having to fend for herself to get the necessary treatments.

“They finally did nine hours of brain surgery on me on Memorial Day on my short-term memory function.”

After surgery and further testing, Jesse’s diagnosis was confirmed as grade four glioblastoma.

“I was told I had one of the deadliest cancers for people under 40,” he says.

A leading researcher in this field at University College London, Dr. Jamie Dean explains that glioblastoma is extremely aggressive, there has been limited progress in treatment over the past 20 years, and the average survival time is only 15 months.

Treatment included six weeks of radiotherapy along with chemotherapy, followed by a further six cycles of maintenance chemotherapy.

Despite the odds, Jesse says post-treatment scans showed no signs of disease, an “almost unheard of” result for glioblastoma.

He has since married his partner Faith, bought a flat and continued his career.

“Given that I’m terminally ill, it’s just all sorts of very normal things that are kind of abnormal and motivating,” he says.

“But I lived a normal life.”

Dr Dean’s work, supported by World Cancer Research, is investigating tailoring radiotherapy intervals to tumor response to improve the effectiveness of glioblastoma treatment.

“We really need to increase the amount of funding going into researching the disease,” he says, noting that despite its poor prognosis, glioblastoma research receives relatively little funding compared to other cancers.

Dr Lynn Turner, research director at Worldwide Cancer Research, describes Dr Dean as a “pioneer of glioblastoma research”.

“Hearing stories like Jesse’s reminds us all of the importance of this work and the hope it gives to those battling cancer and their loved ones,” she adds.