Counting pennies for PSA

I posted this in another thread, but got to thinking that this hasn't been posted in a while and that new folks might get some good info from it. This is a formula that was used here several years ago to offer a simple explanation of just what psa changes mean, in terms we could all understand. I don't remember who first used it, but it is still helpful, unless you live in a country where a penny is worth millions of whatever your currency is, but even then, you know what I mean when comparing psa to a US penny.


Here's a little tidbit, over simplified, to help one understand the PSA results after treatment (an oldie from days gone by here). Consider them in units of value of pennies.

1/10 of a penny is .001 psa
1/2 a penny is .005 psa
1 penny is .01 psa
2 pennies is .02 psa
10 pennies (or a dime) is .10 psa
20 pennies is .20 psa (The second rise above .20 is the start of what is considered a BCR or breakout of PCa by several National Cancer organizations)
100 pennies (or a dollar) is 1.0 psa

As you can see, a 'jump' from .01 to .02 seems like doubling, but is still miniscule in relative increases terms, since jumps really don't start to count or indicate anything until at least 5 pennies or .05 psa and even then, there's variation in machines and calibrations in labs. So a penny difference here and there doesn't mean much if you consider that .20 or even .10 is indication of breakout. So, like the saying goes, it really doesn't pay to sweat the small stuff...lol