Little Caesars

From EatBibek

Vegetarian Pizzas don't contain any animal derived products or byproducts. This includes the dough, sauce and cheese. Source

This was confirmed when speaking to a Little Caesars Rep on 9/3/2008... however she stated that since each store is independently run it would be best to ask the manager as they may in rare cases run out of ingredients and go to the store to buy more instead of using those sent by the company.