Study: Dogs Detect Lung Cancer In Blood With Stunning 97% Accuracy [studyfinds.org]
I don't doubt it. Wogs have amazing sniffters! Did you know Wogs can't go to the bathroom, without first aligning themselves, so that one end is pointed towards magnetic north, and the other end pointed to magnetic south. This is why you see them turning around in circles, before they go doo-doo! (70,000 Wogs were studied, to arrive at that conclusion!).
Yes, dog's noses are incredibly emsitive. My two chihuahua mutts have woken me several times when my blood sugar went too low, without my training them or anything. They could smell my breath annd recognized that it was not right.. Good dogs!