Parents of a schoolboy who died from a brain tumour said their son could have still been alive if millions of pounds promised for research by the government had materialised.
Thirteen-year-old George Fox spent 11-and-a-half months battling glioblastoma, an aggressive and fast-growing cancer.
He died last April after an attempt to get private treatment in the United States - paid for through fundraising - failed when he became too ill to take part in a trial.
Louise Fox said she "got to keep George for just 11-and-a-half months" after his diagnosis and was shocked to find just how little research was done into brain tumours in the UK.
"It's a sad fact when you find out you're actually worse off living in England," she said. "For me, that's totally unacceptable."
George's family are backing a new campaign calling on the government to take urgent action and treat brain tumour research as a priority.
A report by the All-Party Parliamentary Group on Brain Tumours (APPGBT) found despite a promise of £40m in investment in the wake of Dame Tessa Jowell's death in 2018, just £15m had made it into the hands of researchers.
Mrs Fox said the government was letting families, like hers, down.
"If that money had been put forward for research when it was meant to have been, George might still be here today," she said.
"We should have the research and we should have the ability to support people with clinical trials in this country.
"It's not good enough for other families to go through what we're going through now. To face our lives without our son is just devastating for all of us. We are heartbroken every single day. It just doesn't go away."
When George, from Bedfordshire, was first diagnosed with the same type of tumour that killed Dame Tessa, the family was told he had 12 to 15 months to live and were urged "not to Google" the condition.
According to the charity Brain Tumour Research, brain tumours kill more children and adults under 40 than any other cancer.
Yet the condition receives just a fraction of the national spent on research and survival rates have remained unchanged for decades.
MP Derek Thomas, who leads the APPGBT, said: "A total of £40m in investment has been promised since 2018.
"This gave cause for optimism and heralded a very welcome shift in focus especially considering the historic underfunding of research into brain tumours which has received just 1% of the national spend on cancer research since records began.
"However, our investigations have revealed a concerning lack of deployment of these funds with just £15m reaching the hands of researchers in the five years since it was promised.
"The sad fact is that brain tumour patients do not have the luxury of time. The government must act now in order to recognise brain tumour research as a critical priority, appoint a champion, and ring-fence sufficient funds to make a difference."
George's father Matthew Fox said the family had been forced to raise hundreds of thousands of pounds to get their son on to clinical trials abroad abroad because options were so limited in the UK.
But the family said parents should not have to look overseas and are determined to keep fighting on behalf of others.
"We could do nothing for George but hopefully we can do something for other kids in the future," Mr Fox said.
"Where is this missing money that was promised? Are they going to give it? We are hoping they do."
Mrs Fox added: "Brain tumours are indiscriminate. It can happen to anybody and we need to ask what will be happening.
"What will be happening to change this? Where will the money be coming from? Where will the research be coming from?"
A government spokesman told The Guardian newspaper: "We know brain cancer can be a devastating disease and we want to work with researchers, clinicians and others to redouble our efforts to find therapies and new treatments.
"The £40m we have allocated has so far supported 12 research programmes, including analysing of the effectiveness of different radiotherapies and a treatment for epilepsy in patients with brain tumours.
"We have also invested in infrastructure support and we’re taking action to grow the research community, such as workshops for researchers and training for clinicians, to encourage further studies."
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