And by that time you will be 79 -- anyone that age would be delighted to have a PSA of only 1.61.
I think you are reading way too much into your rise from 0.99 to 1.01 in a year. PSA can fluctuate much more than 2% from day-to-day, and of course there are lab fluctuations too. You could retest today and easily have a value somewhere in the range 0.90 to 1.10. If you happened on the 0.90 figure, you would be delighted. But if you had the 1.10 value, you could rework your doubling time, and then you'd really have something to worry about
Your uro says your change is insignificant -- believe him.
As I think Selmer said elsewhere, get plenty of exercise and eat healthily -- those precautions will help stave off lots of other diseases as well as prostate cancer. And in the meantime, enjoy your prostate -- while you still have it