Study suggests cancer is not 'just bad luck'

Cancer is overwhelmingly a result of environmental factors and not largely down to bad luck, a study suggests.

Earlier this year, researchers sparked a debate after suggesting two-thirds of cancer types were down to luck rather than factors such as smoking.

The new study, in the journal Nature, used four approaches to conclude only 10-30% of cancers were down to the way the body naturally functions or "luck".

Richard Lister reports.