PSA testing is done with a number of different methods and products. They range in accuracy from "Ultra-sensitive" to "good enough for routine testing". Also, at the very low level you indicate, there can be a lot of variation either + or - when the same blood sample is subjected to three of four tests instead of just once. Most of the PSA testing is done using the "good enough for routine testing" products. If your father's PSA was determined using one of these tests, then anything below the test's proven accuracy range, typically .1 sometimes .2, then .05 would indeed be considered undetectable as the test can't really distinguish between 0 an .1 level. The time to get concerned about
your father's PSA is if it show a rising trend over several tests.
Prostate cancer diagnosed 08/2006
Robotic Prostatectomy 11/22/2006
Post op Pathology:
Gleason 6 (3+3)
Tumor comprises 48% of Prostate
No extracapsular penetration
Catheter out 11/29/2006, Continent immediately
Used pads as safety measure one week
First Post-op PSA: undetectable (04/2007)
Post Surgery; Vacuum and Viagra starting 03/2007, Injection therapy begun on 4/27/2007.