For the parents of Joel Danziger, a 19-year-old diagnosed last year with an aggressive form of brain cancer, the constant worrying is like living under the threat of a nuclear blast.

“My husband describes it as living with a nuclear bomb and that’s exactly what it’s like. It’s like we know it will go off at some point,” said his mother, Stephanie, who is appealing for donations to pay for a pioneering treatment to extend her son’s life.

A crowdfunding campaign on the website Go Fund Me has already raised more than £47,400 of the £400,000 target from more than 1.3k donors.

Their son, Joel, who was set to take up his place at King’s College London in 2019, began to experience frequent headaches last summer. An eye check-up just before the start of term revealed unusual pressure behind his eyes and retinal haemorrhaging.

A brain scan later showed a golf ball sized brain tumour resting on his optic nerve. The tumour was removed successfully during emergency brain surgery but a biopsy delivered a devastating diagnosis: a lethal form of brain cancer called glioblastoma.

It carries a survival rate time of 12 to 18 months, according to the Brain Tumour Charity.

Mr Danziger, who is also a lover of theatre and culture, has appeared in several plays at Manchester’s Royal Exchange Theatre, including a production of Henrik Ibsen’s A Doll’s House.

In 2013, he was cast as an extra in an episode of Coronation Street where he played the part of a paperboy.

Since last September, he has undergone radiotherapy, chemotherapy and a clinical trial of immunotherapy through the NHS.

“With all the oncologists that we’ve met, we’ve been told that the chemotherapy and the radiotherapy hold it at bay for a while but it will come back,” Ms Danziger said.

“So you can imagine as parents, it’s the most devastating thing you ever ever ever will hear. But Joel has been incredible throughout.”

He was forced to defer university until this year but continued to visit friends and work in Boots until the pandemic meant he had to be shielded.

Earlier this year, the family was forced to cancel a trip to Berlin, where Ms Danziger’s father was born before he fled on the Kindertransport.

“And so he’s been incredibly committed, and then in March with lockdown and that’s been doubly cruel because, as the oncologists said, you need to make the most of the time whilst you’re well,” Ms Danziger said.

She and her husband, who have been forced to “become quasi researchers” in the past year, hope to raise funds for an alternative treatment: dendritic cell vaccination therapy. “We know it’s not a cure but it does prolong life significantly and so that’s what we are trying to pursue,” she said.

They have received “overwhelming” outpourings of support and contributions from friends and family as well as complete strangers. “I think it’s touched a chord. It’s every parent’s nightmare and Joel is such a huge force,” she added.

Within weeks of his diagnosis, he raised close to £20,000 for the Teenage Cancer Trust, which supports cancer patients aged between 13 and 24

To donate to the crowdfunding campaign, visit: www.gofundme.com/f/helpjoellivelonger