Sir – Oh, the dark irony of sitting on my bike, stuck in a traffic jam of buses on St Aldates, reading the advert on the back of a Stagecoach bus telling me that lung cancer is no joke.

My husband, Mike Woodin, died of lung cancer aged 38. Never smoked, worked down a mine or was exposed to asbestos. Did cycle in Oxford city centre all his adult life.

Deborah Glass Woodin, Oxford