Strange PSA readings -- help me make sense of it

I was dx. in 2009. Failed surgery and SRT. Started getting very fast-rising PSA values (2-month PSADT). Went on HT and responded VERY well to where I would do HT for 9-15 months and be able to take an HT vacation for a year. PSA would eventually start rising fast, so back on HT. Eventually I started doing the better scans (C-11 Choline but then Ga68-PSMA). They would find 1 or 2 iliac nodes and SBRT them. Now to my question. Note PSA values:

10/29/2018 7.8
10/17/2018 6.9
9/13/2018 2.3

This again signalled a new scan, then 3-month HT along with SBRT. The SBRT finished 2/14/19. THEN subsequent PSA values:

4/27/2021 0.37
11/27/2020 0.4
6/23/2020 0.38
1/27/2020 0.47
11/15/2019 0.75
8/14/2019 0.59
5/14/2019 0.21

This looks like the SBRT knocked the crap out of my PC as the doubling time is non-existent.
But I thought one gets a PSA bounce with radiation, but isn't that only with primary tx (RE: move from .21 up to .75)? Anyway, what do I make of these readings? Far from undetectable, but nicely...steady. Comments?

Mel

So during the flat 16 months of PSA, have you been on HT or is this an HT vacation? Or some of each? I couldn't tell the timing from your post. Regardless, this all seems quite nice--congrats!

BTW, re bounces, I never had one with my primary radiation.

I find the way the psa is listed odd and confusing I will assume I am missing some thing...and have another cup of coffee...and then do my workout regimen...

you're cured mel

No, you are not cured. Perhaps you are in remission.
Keep watching your PSA and hopefully it will stay around that level for a long time.
But if your PSA rises significantly at some point, further scans may be necessary in an effort to localize the culprit(s).

Looks like you a little bounce in late 2019, and a steady drop since. That's all good.

compiler said...
F8-- Yeah--it's a miracle--clearly, it's the vit D.

Actually, I do take Vit. D3 (2000 IU) daily, along with Avodart and Metformin as per Dr. Lam. Not sure if any of it helps as I was taking it when PSA was rising. I have to credit the SBRT (U of Mich)

Mel

haha! you have great doctors! i take D (2k iu) and turmeric (500mg) and 900mg of saw palmetto daily

Stephen:

Last SBRT was completed 2/19/19, so last scans maybe a month before that. They zapped the 2 hot nodes and some nearby ones. It was 10 days of SBRT.

Dallas : They were all done in my local lab except the last one in April (sent to Mayo). I think different day times.