By Phil Mercer
BBC News, Sydney
The disease has left Tasmanian Devils at risk of extinction
Australia experts say a Tasmanian Devil called Cedric could hold the key to the survival of the embattled species.
The world's largest marsupial carnivore is facing extinction from a mystery facial cancer.
But scientists say Cedric appears to be naturally resistant to the contagious tumours which have killed half the devil population in Tasmania.
Cedric is the first Tasmanian Devil to have shown any immunity from the disfiguring disease.
Infected animals become so consumed by the cancer they can no longer eat or see and eventually die of starvation.
Cedric was captured in western Tasmania last year, along with his half-brother, Clinky.
Both were injected with dead tumours by scientists. Clinky produced no antibodies, but Cedric did and appears to have built-in defences against the mystery illness.
The experiments have now moved up a gear.
Researcher Alex Kriess says the pair have had live cancer cells inserted into their faces.
"They haven't developed a tumour so far," he said. "We injected very few cells so it might take a while until they develop anything that we can see."
Cedric's apparent resistance to the disease has been seen as a significant breakthrough.
The facial tumours are decimating devil numbers on Tasmania's east coast. Cedric is from a genetically different population on the other side of the island.
Scientists hope marsupials that share his genetic pattern could also be immune to the cancer or capable of responding to a vaccine.
If real progress is not made soon, experts worry that the Tasmanian Devil could be extinct within 20 years.