It isn't only pain that warns us that something is going wrong/going on. Some are obvious, some are subtle.
Ever "happen on" finding out you had a condition you were unaware of simply by having an annual physical?
Some diseases are very sneaky stealthy deadly. I think pancreatic cancer is one of them. By the time it is discovered it's too late to do anything.
So maybe we should celebrate? Symptoms are our friends, right?