Using chemotherapy instead of radiotherapy in children with brain tumours reduces the risk of long-term brain damage, say UK researchers.
Radiotherapy can have dangerous side-effects in the brain
Radiotherapy was thought to offer the best chance of survival for such tumours, despite a likelihood of future learning difficulties.
But a decade-long Lancet Oncology study in young children found safer chemotherapy is as good a treatment.
Children under three are particularly vulnerable to radiation side-effects.
A total of 89 children aged under three years who had been diagnosed with a type of rare brain cancer called an ependymoma all underwent surgery to try and remove their tumours.
They were then given an intensive course of chemotherapy "the baby brain protocol" to kill off any remaining cancer cells.
Radiation treatment was reserved only for those children whose disease had spread or progressed.
But of these patients, the chemotherapy treatment managed to delay their need for radiotherapy by more than one and a half years, so the children were older and their brains were more developed.
Overall, 42% of the patients did not receive any radiation treatment for their cancer and almost two-thirds of the children - 64% - were still alive five years after diagnosis - similar if not better rate than with radiotherapy alone.
Around 350 children under the age of 15 are diagnosed with brain cancer each year in the UK, say Cancer Research UK who funded the research.
Around a tenth of these cases are ependymomas - equating to around 35 cases each year - half of which occur in children under the age of four.
Study leader Professor Richard Grundy, professor of paediatric neurooncology at the Children's Brain Tumour Research Centre, the University of Nottingham, explained that radiotherapy in young brains could cause short-term memory loss and reduced IQ.
"We know radiotherapy can be harmful to the developing brain, so avoiding it or using it at an older age if needed will hopefully reduce any learning difficulties these children may develop as a result of this treatment without compromising their chance of a cure."
Dr Judith Kingston, paediatric oncologist at Great Ormond Street Hospital said they were now trying the treatment in other brain tumours.
"It's becoming standard in the UK to treat young children in this way."
Amanda Froggatt, aged 16, was just two when she was diagnosed with a brain tumour.
Amanda was two when diagnosed and is now a healthy teenager
Her mum Diane is incredibly grateful that Amanda was able to take part in the trial.
"There was no need to have radiotherapy because there has been no change since the chemotherapy.
"She had mild learning difficulties but they're very mild and we don't know if it was because of any treatment or just one of those things.
"But with radiotherapy kids can have really bad problems."
Despite suffering a stroke due to the surgery she had to undergo, Amanda, who lives in Mansfield, is now a happy healthy teenager and about to start a foundation studies course at a local college.
"If she hadn't been able to have the chemotherapy she wouldn't be here now."