Ivan is a technology journalist at the BBC. He was diagnosed with a malignant brain tumour in 2002 and has kept an online diary of his life since. He has become too ill to write.
His final plea:
I will end with a plea. I still have no idea why I ended up with a cancer, but plenty of other cancer patients know what made them ill.
If two or three people stop smoking as a result of anything I have ever written then the one of them who would have got cancer will live and all my scribblings will have been worthwhile.
I wish peace to Ivan, his family and friends.