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Posted 9/8/2012 8:57 PM (GMT 0)
 

I think I am still in zero.  Received my two year PSA in the mail today.  The PSA is <.1 using the Beckman Coulter immunoassay method.

Last time it was <.03 using Bayer method.

This time they also did testosterone (407) and sent it off to a different lab (only because I have it done in Erie and results sent to Cleveland).

Question is - what is defference between Beckman Coulter (that may not read below .1) and the Bayer method?

Sorry my signature is not up to date. I have to start deleting something.

Posted 9/8/2012 11:58 PM (GMT 0)
Nothing is going to happen until and if your PSA reaches 0.2 or 0.3 Using the standard test. Worrying about the numbers and the details when you are below that threshold is not healthy, causes a lot of worry and anxiety and accomplishes nothing..JMHO.....
Posted 9/9/2012 12:23 AM (GMT 0)
Sounds like undetectable regardless...I'd go with that...

 

Posted 9/9/2012 5:50 AM (GMT 0)
Bayer is ultrasensitive, the other standard. Less than .1 is considered undetectable. any thing less is icing on the cake. Many use ultra sensitive so as to manage it closer. It is controversial and has been the subject of lively discussions. My opinion is that it, remember my opinion, over treatment, with side effects worse than the arguable "cure"
Posted 9/9/2012 11:39 AM (GMT 0)
Thanks for the enlightenment. It does create anxiety when one does not completely understand all that is entailed in the testing methods. Yes, I think I will take the undetectable and enjoy the day.
Posted 9/9/2012 12:41 PM (GMT 0)
Hope this is not hijacking this thread (I think it's on topic - we're taking about accuracy of PSA testing, correct?).

One of the reasons I canceled my Prostascint scan, other than the fact that its notoriously unreliable, is because of the following statement:

"The presence of HAMA [Human anti-mouse antibody] in serum as a result of ProstaScint® may interfere with some antibody-based immunoassays (such as PSA and digoxin). When present, this interference generally results in falsely high values. When following PSA levels, assay methods resistant to HAMA interference should be utilized. PSA assays which were found to be resistant to HAMA interference were Hybritech Tandem-R and Abbott IMX." ref: http://www.drugs.com/pro/prostascint.html

The way I read this is... because many PSA use murine (mouse) antibodies as the basis for testing, and for a Prostascint scan you are injected with Human anti-mouse antibody, there is a possiblity that the PCa patient may be limited to only certain PSA tests that don't use murine antibodies in order to get accurate results.

This is my interpretation only (and I'm not medically trained), but I'd like to hear others thoughts.

...Jerry
Posted 9/9/2012 2:00 PM (GMT 0)
That is very interesting. I too turned down a prostascint, only because I had heard it was unreliable.  I had other personal reasons, but that is another story.  I did not know about the PSA testing issue. Had I known I would have felt even more confident with my decision.
Posted 9/10/2012 5:44 PM (GMT 0)
If the reading starts with the "less than" sign "<" it means your reading was below the threshhold of detectability for the test used. So there is no significant difference between <.1 and <03. One machine is designed to be more sensitive than the other. The more sensitive one is newer and/or more expensive.

It can also be the case that the lab does not report out the full degree of sensitivity that the machine is capable of reporting. For example, some machines report out to 3 digits, e.g. .027 but the lab may simply round that tho <.03.
Posted 9/11/2012 11:19 AM (GMT 0)
One of the first things my medical oncologist discussed with me when I started my current treatment phase (see below) was the value and necessity of establishing a baseline psa track using the same testing protocol.

Apparently there are something like 6 different protocols for measuring psa. I guess some of that could make sense when dealing with specific needs, etc but that sure was an eye-opener to a layman like me...thought it was a bit crazy - told by someone else to think of it like vanilla ice cream, made by different dairies - all vanilla ice cream; all slightly different, but please...

So today I have a big pow-wow in Boston to review (both psa numbers and new ctscan), after 7 weeks on casodex now having had the psa tested and tracked 3X with the same protocol method since June...

_

Age 63, dx age 60, PSA 2.9 ; detected by dre
Stage t3b Gleason 7 (4 +3) tertiary pattern 5
11/10 Post-prostatectomy path: extensive extra-prostatic growth 60% tumor both lobes; perinural + l seminal vesicle and lympho-vascular tumor invasion; Lymph nodes:14 right obturator; 9 left pelvic (no regional lymph node metastasis)
10/11 adjuvant IGRT radiation 8 weeks
4/10/12 psa rise from 0.3;0.5;0.9 indicated ineffectiveness of SRT – on to medical oncology
5/30/12 negative bone scan; ct scan showing enlarged adrenal gland and 1 pelvic lymph node "involvement"...
6/5/12 initial meet with med oncologist began daily use of pomegranate extract; need baseline psa w/same protocols
6/5/12 psa 1.5…7/10/12 psa 2.0
7/17/12 doc confirmed diagnoses of “aggressive metastatic” pc;
Present: taking 50mg Casodex (Bicalutamide) for 6-7 weeks before new psa blood test + ctscan
9/4/12 ctscan and psa blood tests first since casodex treatment began
9/11/12 to meet with oncologist(s) to review results..
Posted 9/22/2012 8:21 PM (GMT 0)
Proscapt--thanks for letting me know that the weird sign means undetectable. I'm having tests done next week by 2 activities since i didn't know. T3anomo Gleason 8 in 5 cores & 4+3 in 4 cores out of 8--ece & 79 G's & 3 years of lupron-thanks!
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