Variance in PSA results

PSA anxiety can be a terrible thing ! Forget about it ! Save your money ! Get on with your life ! It is what it is, Worry about something else. Why go looking for trouble every month ? If there IS trouble, it will find you soon enough...Worry about it then..

pasayten: Since you have a scientific interest, you can calculate the average and the Standard Deviation. This will allow you to decide on a statistical basis when a value is of concern.

What does your doctor say?

If you’re still with Dr Higano, just do whatever she says. Her reputation as a PCa MO is tops.

You could also just be seeing some of testing error in the test method. Chemistry at these micro levels is tricky and easy to get wrong. There could be variability in the test kit, a margin of error in the measuring machine(s), and our bodies don't behave as consistent as we'd like to think - PSA production can vary due to a number of factors, many benign.

I wish they'd also publish the margin of error for each test. I wouldn't be surprised to find that the lab can only produce results within .1% of the actual value which with your numbers means that each of the values you report could be wrong by +/- .02 ng/ml . Add to that the normal fluctuations in your body and effectively, all your numbers are the same within the known variability of the test method and the biology of the human body.

All too often we get obsessed with test precision and forget why we're doing the test. The point of the game is to decide 1) did treatment work? and 2) is more treatment needed? Post SRT (surgery + radiation) the next treatment mode is ADT which likely wouldn't be started until PSA climbs above 2, 4 or even higher. In this case, testing to .01 or worse, .001, while possibly interesting, doesn't help me decide if I need ADT or not.

Think of it this way - if you were planning to build a road between two cities, knowing how many inches apart they are isn't helpful.

pasayten,

Thanks for posting, that is very interesting. Kaiser only covers the less sensitive test, so I wonder if it has a similar standard deviation, or more? So maybe when I went from 0.2 to 0.3, and then back to 0.2, maybe it was really something like 0.24 to 0.28 to 0.24.

To all... No anxiety or worry here... My intention of the post was that I have a somewhat unique situation of monthly results of ultra sensitive values to show how the numbers can bounce around what seems to be a stable PSA value... Maybe help to take the worry out of other's situations...

Cheers,
pasayten