MILLIONS of people may be “cancer-resistant”, according to experts.

Scientists are being offering up to £20million to work out why some are tumour-proof.

About one in two Brits get cancer but tumours do not develop in everyone who would be expected to get one, such as heavy smokers.

Prof Karen Vousden, of Cancer Research UK, said: “We spend an awful lot of time thinking about why people do get cancer but we haven’t really thought about why some people don’t.

“I’d be hopeful we’d see this in a large proportion of the population.”

If even just two per cent of people show natural resistance that would be more than a million Brits.

Prof Vousden said it was a complicated issue but some may be protected by genetics, their environment or lifestyle.

“Cancer avoidance” is one of seven topics open to pitches for grants from CRUK’s Cancer Grand Challenges pot, with winners decided next year.

Last year it funded research into a rise in young-onset bowel cancer, supported by £5million from Sun columnist Dame Deborah James’ Bowelbabe fund.   

In February, boffins discovered a “switch” that they say reverses cancer cells in another major development for finding a cure to the disease.

Researchers in South Korea said they were able to revert cancerous cells back to a healthier stage.

The team believe they can prevent the progression by exploiting the moment before normal cells irreversibly transform into diseased cells.

Current cancer treatments focus on removing or destroying cancer cells through surgery, radiation or chemotherapy.

But the groundbreaking discovery could let cancer patients regain their healthy cells, it is hoped.