We have had a scare this year - last three PSA tests have increased slightly, but still under the .02 that Mayo clinic views as 'undetectable'.  Had another bone scan, all clean.  Latest PSA went down below the previous three, so hopefully just variations with something as simple as calibrating the equipment at the lab.  Mayo clinic no longer mails us annual tests since our doctor has retired.  We would have to go and have an office visit just to get a blood test.  Having tests every 6 months at our local labs now.