Grandfather has bladder cancer...Again?

My Papa was diagnosed with bladder cancer around the age of forty in the 70's...He was treated and the cancer disappeared, or perhaps stayed stable. My family is very quiet about this, so I don't know a lot of this. But from what I know, I believe it came back in the early 00's, and then it was treated and disappeared. In 2006, my Papa also had a Quintuple (5) bypass artery operation...But he recovered really fast, the doctors were really surprised! However, I am really worried about him...He is just the same but I don't know how advanced or how bad the cancer is...He is a very strong man for his age, 71 years old and still does the garden work, mows, rototillers his 88 acre land, tinkers with his 1930 ford, and his mind is still very VERY sharp. He was a chemist and self entrepreneur, and helps figure out all his 5 children's taxes, (not with his money but by helping with the math portion.) I think he still has a lot of time left...But I don't know if I am just trying to make myself feel better by thinking that.. :(