Yeah, but it's hardly something that many people want/need to learn about. It was sold to the masses as entertainment (the mad looking doctor fitted that bill perfectly), i dont think there's any benefits from having it screened on national television. Those that genuinely want to learn about pathology can study it for themselves or go to these lectures privately.
Just another money-maker for channel 4; if it wasn't they certainly wouldnt be bringing it back for a second 'show'.