This national chain has recently added gluten-free pizza to their menu after learning about gluten-free procedures from the supplier of the gluten-free crust. Boston's has about thirteen different GF pizza combinations for you, and the owners tell me that they have trained their staff to avoid gluten contamination. The pizza crust is also casein free but does have egg whites and soy lecithin. They do not offer casein-free cheese but will make your pizza without cheese if you wish.
I talked to their national chef about other menu items; the rest of the menu has not yet been appropriately screened for hidden gluten in the ingredients. You should stick to the gluten-free pizza for now.
The above update was written by Anne Barfield in July, 2009.