When's the "best" time to do the scan?

[Cackalacky_cyclist]

Well, it appears the salvage radiation done in January '23 (RP in 2019) may have been unsuccessful, as my latest PSA came back at 0.06, 3 months prior was 0.02. Obviously not yet actionable and not yet definitive for failure, but the indication that the barbarian hordes might be regrouping is apparent. My MO is on top of it, scheduling my next PSA 6 weeks out to develop the first PSADT trend. Right now, he's indicated that he'll do a Pylarify PSMA PET scan near a PSA of 0.5. Unlike some, I have time to plan the scan and my possible next treatment.

And that's where I'd like some opinions from this group - What PSA / PSADT should determine when to pull the trigger and get a scan, and is Pylarify the "right or best" scan in this case? Did you have a similar decision to make, and would you have approached it differently based on what you've gone through?

I feel like I'm playing "The Price is Right" at this point; get as close to the magic PSA number without going over (to metastasis).

I understand there is documentation describing successful results of PSMA scans with PSA < 0.5, and even PSA < 0.2 (Thank you to Tall Allen's blog) though the lower the PSA the lower the probability. However, I haven't found such specifically for Pylarify.

[Cackalacky_cyclist]

Found the study I was looking for: pubmed.ncbi.nlm.nih.gov/336...

[j-o-h-n]

When's the "best" time to do the scan? Definitely not while riding your bike.....

BTW Cackalacky, that's a great spicy UserID..................I'm torn between calling my wife or my girlfriend by that name (maybe both, this way keeps me from getting them mixed up)...

Good Luck, Good Health and Good Humor.

j-o-h-n Tuesday 10/17/2023 7:07 PM DST

[Tall_Allen]

There is no such thing as a PSADT for PSAs below 0.1. But PSMA PET scans are likely to be useless when PSA<0.5. The data are in my blog.

[RMontana]

I am in the same boat…looking at my uPSA (ultra low) values rise after radiation n HT. Don’t think there is much we can do till the PSA rises. You max want to not let it rise. I plan on doing intermittent HT… ride the rise out as long as possible See here

healthunlocked.com/active-s...

This article does speaks to your values of PSA at which u want to get a PSMA PET. I sm sorry that our system had deleted my publication Links… not sure why. But here is a summary.

healthunlocked.com/active-s...

[Justfor_]

If you look at my profile I have 1428 responses to others' posts. Give or take, 10% of them, read: "Blind sRT is a big NO-NO. PSMA pet scan first". I also have started 2-3 threads on the subject as I got tired of repeating myself.

healthunlocked.com/prostate...

I am stating the above info to make it absolutely clear that I have my own personal opinions that don't align with silly docs' parroting like: "There is no such thing as a PSADT for PSAs below 0.1").

Back to your question now, what I would have done in your (current) state? (our cases are very similar, check my bio). Take the PSMA pet scan when PSA gets above 0.1, but definitely bellow 0.2. This is what I will do when my Bicalutamide maneuvers start failing.

healthunlocked.com/prostate...

[Hawk56]

So, here's my clinical history. In conjunction with my medical team based on data such as TA and others describe, our shared decision criteria about when to image was three or more consecutive increases spaced 2-4 months apart, PSA between .5 to 1.0.

The data showed that waiting for PSA to be .5 or greater significantly increased the odds of the PLarify scan showing where my PCa was. Wwe felt it did not entail any risk to the outcome of a treatment decision - i.e. letting it get out of control.

The scan did show a single PLN in the right hip area, we did SBRT and currently on Orgovyx. Medical team and I have been happy with the response and have labs and consults every three months to decide on continuing treatment, modifying, or stopping.

Could we have imaged below .5...yes,would it have found the PN, we'll never know. What I can say is had we done that, had it found the PLN, it would not have altered our treatment plan.. That's a question you and your medical team may want to discuss, the cost-benefit of waiting for your PSA to rise and thus increasing the possibility of the scan showing where the PCA is versus scanning earlier and showing nothing. I tink the critical question is, does it change the treatment decision and plan...!?

Radiologist and oncologist are leaning towards 12 months, if PSA stays undetectable, stop and actively monitor. Oncologist has not thrown an ARI into the treatment plan yet based on my response to SBRT and Orgovyx. He has also discussed 24 months...We'll see.

Kevin

Clinical History

[Jmr11820]

What were your PSA numbers in the 2 years post surgery? Was it actually 0.00?

[Cackalacky_cyclist in reply to Jmr11820]

Duke reports undetectable as "<0.01".

[Horse12888]

FWIW, my PSA is 0.40, and the doubling time is 11 months. With my MO, I've decided to wait till it hits at least 0.5.

[ron_bucher]

"...Obviously not yet actionable and not yet definitive for failure..." was not the way I looked at my somewhat similar situation. Aggressive proactive treatments gave me 5 more years of undetectable PSA plus freedom from ADT. Details in my profile.

[Cackalacky_cyclist in reply to ron_bucher]

I assume you're alluding to your 2016-17 treatments, and that you did not wait for a PSA "high enough" for the scans available at the time, and hence didn't do any scans prior to your trimodal therapy.

I'm of the same mind - hit it early and hit it hard, but I'm also trying to base my next treatment decision on "am I metastatic" or not. I can either assume one way or the other and tailor the treatment towards "curative intent" (pelvic radiation +/- ADT +/- ARSI) or go systemic treatments (ADT +/- ARSI +/-chemo +/- ...). Your story does offer another option I hadn't contemplated which I would consider the schrodinger treatment - I am both non-metastatic and metastatic until I get a scan, so don't get the scan and treat both conditions. I thank you for that insight and possibility. Of course the side effects are a concern, but I have to deal with my own risk/reward calculations

[ron_bucher in reply to Cackalacky_cyclist]

Since you had RP and local area radiation, the cancer can be anywhere outside of that area. My radiation oncologist said he has never seen cancer return to any area he has radiated in any of his patients. So unless your radiation oncologist missed something in the local area, I think your case is "metastatic".

My side effects from radiation of abdominal lymph nodes were less than what I remember from my radiation of the local area. My side effects from Taxotere were very manageable and well worth the years of freedom from ADT.

Dr. Scholz's theory in prescribing my triplet therapy before scans reveal tumors was 1) Taxotere will kill the tiniest tumors regardless of location and 2) the most likely location for tumors too large for Taxotere to kill would be in those abdominal lymph nodes, and 3) virtually every treatment works better the earlier you get it.

I'm trying to avoid ADT as much as possible. I found it to have the worst side effects of any treatments I've ever had.

[Cackalacky_cyclist in reply to ron_bucher]

Interesting thought process; well worth discussing with my MO. Thanks much!

[SCreader]

My Pylarify scan between RP and Salvage RT found a suspicious node at a PSA of .17 and helped to tweak the salvage RT treatment plan.