The NHS can and does regularly fund children to receive proton beam therapy in the US (usually in Oklahoma and Florida) in cases where it is shown to be effective and/or the child is too young for radiotherapy (usually under age 4). We knew a couple of children who went. They hope to have a centre offering it to children set up by 2017 here in the UK.
It is not an effective therapy for that form of brain cancer even in the US.
I wanted to run away with my daughter after her 4th round of chemo. She was so, bar the Hickman line, NG tube and bald head, well.
But her form of leukaemia was not curable with chemo. This was well-known and established. The only way to try to save her life was to try the risky allogenic stem-cell transplant.
She died of secondary infection/pneumonia less than 2 months later.
BUT, had we not tried it, she would have had zero chance of long-term survival.
So I understand, what a horrible decision this is. DD1 had far, far less of a chance of long-term survival even with successful stem cell transplant than little Neon, so the urge to just run off was strong.
But you have have to try the best you can and put aside your fear and pain for that child. And be the bigger person.