But last month he confirmed he'd been cured after undergoing an experimental form of treatment in May, which resulted in the complete removal of a 3kg pancreatic tumour.

Now Johnson tells the BBC: "Steadily my health is recovering - I'm getting my strength and my weight back. The difficult thing is adjusting mentally. I'd dealt with this last year by absolutely accepting, never entertaining false hope, never pursuing any cures or anything. I thought, 'I'm going to go and I'm going to make the most of what I've got left.'