Oh yes! I've come across this book several times in my Google searches and it's got a LOT of good points, like pancreas exhaustion and the need to eat sweetbreads. :)
I think it's a little narrow tho to say that cancers are only caused by lack of enzymes, as there are many factors that can cause impaired digestion, undigested foods, toxic overload, etc. But enzymes play a HUGE part of the scenario!