A brave Irish girl, who was at one stage given just a five percent chance of survival, has taken a huge step on her road to recovery after she was declared cancer-free by doctors in the U.S. for the first time in three years.

Robyn Smyth, 11, who suffers from neuroblastoma and who has battled childhood cancer since the age of three, was declared disease-free for the first time in 2009.

But the youngster relapsed three years ago when a tumor broke through her jawbone and the cancer spread rapidly to her spine, legs and pelvis.

Her mother Bernadette Dornan, from Whitehall in north Dublin, had feared the worst after doctors gave her daughter just a five percent chance of survival.

But determined Dornan refused to give up hope, and after identifying a groundbreaking medical trial at Helen de Vos Hospital in Grand Rapids, Michigan, she launched a successful fundraising campaign to cover the colossal medical bills.

And now Dornan, who also has a four-year-old daughter called Millie, said she finally has reason to celebrate after her daughter's latest scan results were clear for the first time in three years.

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"It's wonderful news and something I couldn't have dreamed of a few years ago. I thought the treatment in the U.S. was the best option for Robyn and the scan results show that it's worked,” Dornan said.

"Of course this doesn't mean she's out of the woods yet, because there's always a big chance of the cancer returning. But this is a huge step for us and it's taken three hard years to get to this point. It's a great day."

The youngster is due to have further tests in Michigan, which will enable doctors to assess whether she's eligible for a further pioneering trial.

However, the costs of the two-year trial for children whose cancer is in remission will be in the region of $250,000, meaning the youngster is facing another desperate race against time to raise funds.

"It's vital I get Robyn on to this trial as soon as possible, because as great as the news we've just had is, her cancer could still return at any time,” Dornan said.

"So this is the best option we have to make sure she stays healthy. I've $120,000 left to cover her fees, but need to raise at least $130,000 more to cover the rest of the costs.

"The people of Ireland have been great and I can never thank them enough for getting us this far. But we've still got a long road ahead."

For more information and to donate visit www.robynslife.com.

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11-year-old Robyn Smith is battling cancer: Two-year trial for children whose cancer is in remission will be in the region of $250,000.Twitter / @RobynslifeSmyth