Facebook followers, he wrote: 'As a proud patron of Velindre Cancer Centre, I've trekked the world, hosted chaotic quizzes and star-studded comedy nights.
I've met and made friends with so many inspirational staff, patients and their families. It has been a huge part of my life for the last ten years. 'So while I never imagined that I would be a patient here, I know better than anyone that I am in the best possible hands. 'The NHS care I'm receiving is incredible.
I wouldn't wish this on anyone. . . but who knows, maybe I'll come out the other end with a new stand-up show and a 40 minute rant about orange squash. 'Thank you everyone for your support over the last few weeks and months (and years).
I'll be disappearing for a while and won't be commenting further, at least not for now, whilst I focus on my recovery. ' After previously cancelling shows due to issues with his throat, he paused his Book of John book tour last week.
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