By Clark Collis
Updated July 01, 2010 at 05:26 AM EDT

British writer Christopher Hitchens has revealed he is to undergo a course of chemotherapy. In an “Update” published on his publisher’s website, Hitchens announced, “I have been advised by my physician that I must undergo a course of chemotherapy on my esophagus. This advice seems persuasive to me. I regret having had to cancel so many engagements at such short notice.”

The prolific and provocative Hitchens is the author of a number of books including the 2007 bestseller God Is Not Great: How Religion Poisons Everything. Earlier this month, he published a memoir, Hitch-22.