Image copyright Philly Simpkin Image caption Ollie struggles to hear in big crowds and has to sit at the front of the class

Ollie, 12, wants to learn to play the drums but he can't after losing some of his hearing following cancer treatment when he was only a few months old.

Now scientists have discovered that a new drug given hours after chemotherapy can reduce the long-term side effects of cancer treatment.

Hearing damage in children reduced from 63% to 33%, trials by Great Ormond Street Hospital researchers found.

Cancer Research UK said no child should suffer a disability after treatment.

Ollie Simpkin, from London, was diagnosed with hepatoblastoma, a rare liver cancer, when he was five months old.

He had surgery and eight rounds of chemotherapy, but the drug which successfully shrank his tumour - cisplatin - also damaged his hearing, common in around two-thirds of children treated with the drug.

"He has lost the top end of his hearing which means if there's a lot of background noise he can't hear anything," his mum Philly explains.

This means he has to sit at the front of class in school, but his parents are thankful that he does not have to wear a hearing aid.

"He is fine conversationally - it's like having glue ear," she says.

Image copyright Philly Simpkin Image caption Ollie was diagnosed with a rare liver cancer at five months old

However, he has been advised not to take up the drums because of the risk of further damage to his ears.

Ollie was not given a drug called sodium thiosulphate (STS) after his cancer treatment, but a trial of 109 children with liver cancer suggests it could have saved his hearing.

STS was given to a group of children several hours after cisplatin and their risk of hearing loss was reduced by nearly 50% compared to another group of children treated only with chemotherapy.

There was no difference in overall survival between the groups or in the chances of the cancer returning, the researchers said.

'Utterly debilitating'

Dr Penelope Brock, trial lead and paediatric consultant at Great Ormond Street Hospital, said: "We're lucky to have such an effective treatment for this type of liver cancer. But like many cancer treatments, there can also be long-term side-effects.

"For children treated with cisplatin alone, a huge proportion are left with permanent hearing loss, which can be utterly debilitating."

This happens because although the cancer drug is rapidly removed from the body following treatment, it is retained in and damages the cochlea, the portion of the inner ear responsible for hearing.

Image copyright Philly Simpkin Image caption Ollie and his parents are delighted that he is now cancer-free

She said even mild hearing loss could severely impact a child's future development.

"This treatment combination could help ensure that parents aren't faced with an upsetting scenario where successful cancer treatment comes at the cost of their child's hearing," Dr Brock said.

Prof Pam Kearns, Cancer Research UK's expert on children's cancers at the University of Birmingham, said no child should have to suffer a disability as a result of their cancer treatment.

"Hearing is precious and we're delighted to see that we can safeguard the future development of more children, without compromising the chance of curing their cancer."