PSA when is it classed as undetectable

Hi Brizzy1 again a warm welcome to the community. I don't know enough to answer your question with any detail but I'm sure one of the lovely folks in the prostrate thread will be along soon to help with your query. 

Hello Brizzy1 

That's a very good question and I can't give you an answer as all hospitals and indeed G P's tend to have different opinions.

I go by the basic rule of thumb they all use:-

* Your nadir or lowest PSA reading is usually the one 18 months after the completion of Radiotherapy.

* No action will be required unless you have 3 consecutive PSA rises or your PSA jumps up a whole 2 points above your nadir.

I hope this helps and sets your mind at rest.

Best wishes - Brian.

Hi Brizzy1 . Yes it does indicate that it is undetectable at the moment after radiotherapy. There are different definitions of less than 0.2 or 0.5. Another definition on prognosis is the level of less than 0.1 within 6 months post radiotherapy.

https://dailynews.ascopubs.org/do/psa-nadir-6-months-after-radiotherapy-strongly-prognostic-long-term-survival-patients

The combination of RT and HT reduces the PSA a lot faster than just RT. Once you come off the HT the PSA can increase to a new baseline. Brian is correct with his figures but added in to this is the rate of any increase (doubling time) with 6 months being indicative of a worse outcome compared to a long doubling time.

You are doing very well.

Hi Brizzy 

I think the most important thing here is that PSA doesn't start moving upwards or very little and then when U come off the HT hopefully PSA still stable although could move a little bit.

It's the problem we all face when treatment over, is the PSA going to start rising again, I still worry about it 7 years after treatment finished, obviously not all the time but when PSA test due.

Good luck

Steve 

Hi Dizzy

In Poole < 0.03 was deemed undetectable. 

Regards

Stuart

Hi !

It may go lower. When you don’t do ultrasensitive PSA then ’undetectable’ is < 0.1. We use that in Sweden and Finland. Then you have ultrasensitive PSA measurement and ’undetectable’ is < 0.01. You probably can go lower but you start realize that measuring doesn’t give you any meaning at all, especially if you still have your prostate left. Even under 0.1 you are talking extremely low amount of ’particles’ in your blood and there are actually some ordinary activities like exercise, sex and etc. that can affect PSA. So under 0.1 you’re often in a good place after radiation and ADT

Even a < 0.01 doesn’t really define any scientific markers when it comes interpreting the status of any prostate cancer. With that said, it’s a very good respons to have 0.03 in PSA after radiation and ADT and I think you can relax and enjoy that your treatment has worked fantastic and the future will tell when you start to come of ADT. But, like i Said, the prognosis looks really good 

Best wishes - Ulf