THE family of a four-year-old girl with an extremely rare and aggressive childhood cancer face a race against time to raise £500,000 for life-saving treatment.

Experts say Fraja Simpson has a much higher chance of survival if she fly to the United States to undergo a range of pioneering drug treatments unavailable on the NHS.

Her parents have just five months to raise the money.

Fraja, of Leeming, North Yorkshire, was initially diagnosed four weeks ago with neuroblastoma - a nervous system tumour affecting fewer than 100 UK children a year.

But her consultants discovered the presence of an even rarer gene which makes the cancer more aggressive.

Fraja has already begun intensive treatment at one of the region's hospitals - which includes high-dose chemotherapy, radiotherapy and stem cell replacement.

She then faces a 50 per cent chance of relapse - which just one in 20 children survive.

However, her chance of recovery will dramatically improve if she benefits from the US treatment within 100 days of healthy stem cells being reintroduced into her bone marrow.

Fraja's father Garry, originally from Consett, County Durham, said: "We have gone through the tears, but we have got to stay strong for Fraja as we wouldn't be able to live thinking we had not done all we could."

When she returned home from hospital last week following a chemotherapy session her hair began to fall out in large clumps.

Parents, Michelle and Garry, then set about the heartbreaking task of shaving off her remaining golden curls to improve her self-confidence.

"Fraja stared into the mirror and, after hours of silence, said 'I don't look pretty any more and I look like a boy'," he added.

He said that watching his daughter's rapid journey from joyfully playing a sheep in the school nativity before Christmas to suffering the effects of neuroblastoma with MYCN amplification - the rare gene which exacerbates the cancer - has been devastating.

"One of the biggest shocks was seeing all the kids undergoing treatment at hospital and knowing that was the journey we would be going on."

Mr Simpson, a former pupil of St Bede's School, Lanchester, said the diagnosis came as his father, Terry, of Consett, County Durham, fights terminal cancer. His mother, Ann, underwent surgery for stomach cancer last year.

The flight sergeant with 90 Signals at RAF Leeming, North Yorkshire, and a veteran of Afghanistan and Libya tours, said: "When we were told the disease only affects a few children in Britain we thought why us?"

Fraja's mother, Michelle, a pharmacy technician at St James's Hospital, Leeds, said her little girl is already feeling the effects of her treatment, but remains upbeat.

"She calls her tumour Bob and asks people if they have a Bob in their tummy," she added.

The tough treatment involves chemotherapy over 70 days, stem cell harvesting and replacement, surgery to remove part of the tumour, high-dose chemotherapy, radiotherapy, differentiation therapy and immunotherapy.

Fraja's consultant Martin Elliott, of Leeds General Infirmary, said: "There is still a relatively high chance that her disease could relapse and relapsed neuroblastoma generally has a very poor long-term prognosis.

"We are trying to encourage her parents to be optimistic as Fraja does have a potentially curable condition."

If the first five stages of the treatment are successful, Fraja's parents can opt for treatment in the United States, which offers a greater range of therapies than the NHS and would cut the chance of relapse to 30 per cent.

Mr Simpson said he is "gobsmacked" by how friends, family and the RAF Leeming community are already throwing themselves into fundraising events for Fraja.

The couple's other children Howie, 14, and Erinn, 12, attend Durham School, from where two nurses are planning to walk to RAF Leeming to raise funds on Mother's Day.

For details about the campaign, visit facebook.com/FrajaEllieAppeal. Donations can be sent to the Fraja Elllie Appeal, Yorkshire Bank, sort code 050631, account number 35520051, or by Paypal on frajaellieappeal@yahoo.co.uk