Dr. Leon Yoder: Endoscopic ultrasound is a technology that we use here almost every day. This is a technology where we're using sound waves. And the sound waves are then transmitted by what's called a transducer, and that sound wave then is picked up by a monitor. On that monitor, we can read the contents of a bowel wall. We know the bowel wall is thickened. It has five layers. And because of these sound waves, we can see actually every one of these layers. And we use that through a scope. We put a scope down into the stomach, or we put the scope into the colon. And then with these sound waves, we're able to see and stage a tumor. So, for instance, if you have an esophageal cancer, we were able to see now the depth of that cancer as it goes through the walls of the structures. Does that make a difference? It does make a big difference because it involves how best we can treat this type of cancer. It may be surgical treatment. It may be chemotherapy. It may be radiation. Or it may be a combination of any of those. But it certainly has given us a better opportunity now to stage a cancer where we get the most specific type of treatment for it.