Posted 12/8/2016 6:34 AM (GMT -7)
I can explain the different readings. I also had a 0.006 reading in September and questioned the result by emailing and then speaking to a director of Labcorp in NJ. I understood that the low limit of detection is less than 0.014 ng/ml and asked then how I could get a reading of 0.006. I was told that the reading represented a computer glitch and the test result was canceled and reissued as 'less than 0.014'. I was also told that other people's results with this same glitch would be reissued. Interestingly my result this week is now 0.012 which is below the limit of detection. My take on this after discussing with the lab director, in Sept, is that the 0.006 is the number that the test determines but has a high degree of error in it since it is very low and the technique is not so sensitive to produce a reliable and consistent number. So Labcorp cannot really stand behind this number with any degree of certainty, which is why they should usually report as less than 0.014.
So remember that the test uncertainty is very high at these levels, and that there can be traces of psa produced by other organs in the body, so just consider that we are in good shape with numbers as low as this, and as long as we are less than 0.1, we do not really care what the numbers are. You cannot establish any data trend with these low numbers. Hope this helps
psa 4.5, 4 cores by MRI guided biopsy 2/13 after 2 neg biopsies a year apart at psa 2 &3, in 2011-12. gl 4+3, 8% cancer neg margins, neg nodes
RP 3/13, gl 4+3, PSA < 0.008 from 5/13 - 7/14,
PSA 0.01 10/14, 0.03 2/15, 0.04 5/15 0.046 6 /15 (different lab), 0.79 9/15, 0.087 10/15, 0.108 12/15 , 1/16 firmagon & lupron - psa 0.015, 4-5/16 IGRT, 37 sessions,
9/16 psa <0.014, 12/16 0.012