This is the short edition of Morales, first broadcast on the BBC World Service.

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Hello and welcome to Morales on the BBC World Service.

I'm Tim Harford.

Headlines and news bulletins around the world

just couldn't get enough of a new study of cancer published at the start of the year.

Here's the independent newspaper from the UK.

Most cases of cancer are the result of sheer bad luck.

But more or less listeners, Philip, Riann, Simon, Alex and David,

each raised a quizzical eyebrow spotting that there was some confusion in the reporting.

They asked us to investigate and we discovered that to understand this research

it helps to go back to basics. What is cancer?

We asked Peasy Myers, a biologist and associate professor at the University of Minnesota,

Morris in the United States.

Cancer is actually a pretty complicated disease.

I mean there's a lot of different kinds of cancer.

But basically what you've got is a set of cells that are undergoing uncontrolled replication

and are often doing things like being invasive and penetrating into other tissues they shouldn't.

So it's basically a small population of cells that have got nuts and have decided to take over.

Right, so what about this new research that says cancer is largely a matter of bad luck?

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