How long after radiation treatment did you repeat the PSMA/PET?

I am not a Doc, but had this scan done. Up to your doctor, mostly driven by PSA level and symptoms.

I'm getting off a 24 month treatment of ADT and doing PSA tests every three months there afterwards. If and when the PSA rises, getting PSMA PET imaging will be a likely next step. My agreement with my health team is that we have talked about this, and don't want to over think it, but will keep each other updated if new advances in the field or new concerns arise.

Congrats on getting off ADT!

Good luck on your journey!

Hey @gently
I'm with @edmond1971 here. It's not so much a time thing as an indicator. If the PSA starts to go up, I'd probably start doing research on where would the PSA level have to be to be likely to give me the most accurate results.

If the metastasis is at the micro level, the PSMA scan might miss it. (which may be what happened with my first scan given my history)

I had the scan after my PSA went from .039 to .091 in 3 months. It was negative although there was obviously something going on. The cancer was probably still too small to be seen. There has been some research on this topic and one of the other members here has shared some links and charts regarding this. @kujhawk1978 I think has done a lot of research on this topic.

I then had salvage radiation and ADT for two years. (just got off that in June "knocks wood")

My timeline/history during that time was:
09/02/21 Radical Prostatectomy -
10/22/21 PSA Result of < 0.1
01/26/22 PSA Result of 0.039
04/26/22 PSA Result of 0.091
05/20/22 PET CT PSMA for Prostate Negative results for metastasis

Best of luck to you!

Rule of thumb, PSA 0.2 to show on PSMA scan. However, the scan sometimes shows mets at lower levels

Hey @rfghmd

I'm guessing by your handle you're / were an MD? I've always been under the impression that that without a prostate, your PSA creeeping up, it's kind of a linear correlation, the higher you let the PSA go, the more likely you'll find where it is with the scan?

Obviously, that can be a little like Russian roulette, but, I've seen a study indicating that even at PSA < .5 ng/ml the detection rate is only 38%. Obviously I had mine way lower than PSA .2 and probably wasn't a good idea looking back, but, I'm trying to get a handle on it for the future. Hopefully I won't need it, however, if "you fail to plan, you plan to fail"

Yes, I'm a recently, because of my cancer, retired internist. My prostate cancer knowledge prior to becoming a patient myself, was extremely limited. I referred patients at risk. This cancer is so unpredictable. I want a yearly scan. MO wants to wait till PSA >0.2. The cancer mutating further can lead to NO PSA production.

rfghmd, thanks. I'd like to know more about the cancer mutating further ending PSA production. It makes sense that a bone or any metastasis would cease to produce PSA. Will you prevail and have the PMSA/PET ? Change MO?
Have you a handy link?

Healthunlocked.com is a good website where you can get a lot of info. Get questions answered. Try it. I learned a lot there.