Apparently, despite his name Christopher, he may Halachically be Jewish!
As long as a man is still alive, he may yet repent.
If Hitchens used his talents to renounce his atheism, and became a theist, or even a partly observant Jew, he may yet redeem himself and get his Olam Haba.
As for him 'dying', with modern cancer therapies, cancers which until a few years a go would have killed a person within months, can now be endured for years, decades even.