From a Guardian interview with Umberto Eco:

It is claimed that he called the film of The Name of the Rose a travesty, but that seems unlikely. He says only that a film cannot do everything a book can. “A book like this is a club sandwich, with turkey, salami, tomato, cheese, lettuce. And the movie is obliged to choose only the lettuce or the cheese, eliminating everything else – the theological side, the political side. It’s a nice movie. I was told that a girl entered a bookstore and seeing the books said: ‘Oh, they have already made a book out of it.'” More laughter.