TBF they did make similar clams about expert systems (older readers may remember this form of AI) in limited diagnostic fields back in the 80's. Modern AI that can has the storage and processing power to chomp through a huge pile of imaging data and has adaptive abilities should be really rather good at this sort of thing. There must be a huge volume of training data (potentially) available given the national screening programs that take place in various parts of the world. These claims seem quite reasonable to me.