Hi, Mugaboo. I logged onto the forum this morning to report almost the exact same experience and to ask the very same question you have. I had DaVinci surgery in June 07. In Sept 07, my PSA was undetectable at <.01. In March 08, it was .02, and dr said nothing to worry about. Last Friday, the latest report came in at .07. Dr again says he is not overly concerned and that people with my profile have only a 6-8% chance of recurrence. My post-surgery path was clear margins and Gleason was 3+3=6, a non-aggressive form of cancer confined to the prostate, and final stage of T1c. He told me that other tissue can create PSA -- including the pelvic bed where prostate was, the penis itself, even the pancreas, and that any inflammatory process involving those sites can result in a minimal spike. He told me to wait another 6 months to check again. I requested three months, so I will try again in mid-December. I'm trying to remain "unconcerned" and positive, but it is a bit difficult to put this out of my mind completely.
I appreciate the information you all have provided. My dr didn't say anything about .4 being a threshhold, but did say that unless and until the level rises to .1, he will remain unconcerned. ('Course that's not too far from .07!) At that point, he will consider radiation. I guess we're on a similar journey, Mug! Let's keep each other positive.
I'm off on a two-2week vacation out of the country. I'm going to take the dr's advice and put this out of my head -- at least for that long!