It’s a hard concept to imagine, but not all of the things we call ‘cancer’ need to be treated. Some ‘cancers’ are temporary changes to cells that will reverse or disappear with time, and others are so slow-growing they’ll never cause any problems.

For some cancers, over-diagnosis leads to unnecessary treatment and avoidable side effects. In others, we desperately need to be able to detect the disease earlier – but do so in a more accurate way.

In lung cancer, for example, X-ray scans can’t distinguish between spots where there is nothing to worry about, or the early stages of an aggressive cancer that needs prompt treatment.

This is a Grand Challenge that would both save lives and improve quality of life – for millions of people worldwide.