First PSA of 2018

Its 2 weeks shy of my 1st year RALP anniversary. I just got the results from a Abbott ARCHITECT assay and was relieved that it was < 0.008

Next month, I have a routine screen by my Endocrinologist who includes a PSA in my panel and I know it will be around 0.04 because he uses a Siemens assay. At least I know that Siemens is the only one out of five machines that gives me a detectable reading

Saipan,

Both my Urologist Surgeon and my Endocrinologist are in the same hospital. The hospital uses a Siemens immunoassay for all its tests. After my RALP, I had a detectable reading of 0.050. Because my pathology was good (no EPE or margins and G7), the Urologist was a bit puzzled that the reading was detectable. So, I went to an independent lab that used the Abbott ARCHITECT assay and it came back undetectable (<0.008). I then went on a spree of testing at other labs, which included Labcorp (Roche COBAS) and Quest (Beckman Coulter) and all came back undetectable. Meanwhile all my follow ups at the Urologist and even the screening by my Endocrinologist, both of whom use the Siemens assay, showed levels between 0.029 and 0.059. My Urologist told me to stop testing with the Siemens at his hospital, so I now go to an independent lab that uses the Abbott, because it is a 3rd gen machine that tests down to 0.008.

As to why I have detectable PSA on a Siemens assay, I've started a thread on it a few months ago if you search. Siemens uses goat and mouse monoclonal antibodies in its reagents and something in my blood (heterophilic antibodies possibly) appears to be binding to these reagents and interfering with the Siemens test, producing a false positive. The only way for sure is to do two tests on my blood, one normal one and another titrated with heterophilic antibody blocking agents. If there is interference, the sample with the blocking agents should be lower or undetectable. As of today, I am unable to find a lab in the US that has a Siemens assay and is willing to acquire the blocking agents so I'm stuck. My regular doctor has expressed some willingness to help, but there is some cost as well. The previous research which documented these issues were all done in a University research environment, which I don't have access to.

Thanks, WeightLoss. I think I'll go watch Netflix or something instead of obsessively researching while I hyperventilate waiting for the test result.