The phenomenon could indicate that the immune system of devils is starting to fight back and slow the progression of the transmissible cancer - a sequence that is occurring in an exceptionally short timeframe.

The devils were found in populations in six different areas in the East and the North-West, however the growing resilience is likely to be in other areas as well, given researchers can only focus on certain areas at a time.

University of Tasmania devil facial tumour disease expert Rodrigo Hamede said this was the first step for resistance and the genomic bases would be investigated to gain more understanding of why this was occurring.

"The really important aspect is that if this adaptation to the disease is occurring by natural selection, it should be a heritable response, and hopefully that will build more resilient populations in the future," Dr Hamede said.

"The 50 have had different responses. A very small number have been able to fully recover, others have reduced the size of the tumour but haven't been able to fully recover, but have fought it to a point that they can survive another year and allow another breeding season.

"That is great news."

The first isolated case of a devil appearing to fight back against the facial tumour was found in the North-West in 2009, a further five were found in the next five years, and even more have been found in the last five years.

Dr Hamede said the study of these resilient devils could have wider benefits.

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"We have to put this in the context of the evolutionary process. These things normally occur at time scales much longer than just two, three, four generations - for humans, we learn to coexist with them through 100,000s of years," he said.

"It is adaption to diseases that is important to threatened life. If we find more genome involved in this adaption, it has implications for other species evolving and adaption to infectious diseases.

"The devils are a wonderful case study to come up with."

Some of the world's leading Tasmanian devil facial tumour experts will converge on Launceston this week for the Ecological Society of Australia Conference.

Other topics include contingency plans for devils suffering the second type of devil facial tumour disease, the efficacy of vaccines in bait, the importance of devils in the ecosystem for protecting threatened species and the role of male devils in spreading facial tumours during mating season.