The drug has been shown to shrink tumours

RAF Cpl Nick Lock, 30, from Newton Abbot, said the drug Cetuximab was his last chance as he was immune from previous drugs he had been given.

The drug costs around �700 per week and only works in 25% of patients.

Devon Primary Care Trust said it could not fund it because its effectiveness had not been proven.

'Medical miracle'

Mr Lock, an aviation engineer, beat colon cancer four-years-ago, only for it to re-emerge in his lymph nodes last year. He has had two sets of chemotherapy.

"I had cancer once and beat it, and got told it would be a medical miracle if I made it through the night and that my father and brother should fly over from Cyprus to say goodbye," he said.

"I proved the doctors wrong before and now they're not going to give me the chance to fight this."

His father Roger Lock said: "It's Nick's life - he's my son, I love him to bits and we're going to give him every possible fighting chance and if this drug will give him a 25% fighting chance - which is his last chance - then those odds seem pretty good to me and I'm going to go for it."

The drug has been shown to shrink tumours allowing the possibility of surgery, but is not a cure.

I proved the doctors wrong before and now they're not going to give me the chance to fight this. Nick Lock

It was initially given the go-ahead to patients in Wales however that decision was overturned.

In the statement, the trust said: "The National Institute of Health and Clinical Excellence (NICE) has published guidance on the use of the drug, Cetuximab.

"NICE has not recommended Cetuximab for use by the NHS, as its effectiveness has not been proven for this use.

"We are required to follow guidance set out by NICE, which means we are unable to offer funding to patients requesting this drug."

Mr Lock's squadron have been trying to raise money to help him, however he will have to have the drug administered privately.