My two cents, fellow member of this darn club, layman, 10 years...

The question to consider asking is:

Would waiting to image change the treatment plan?
Would waiting to image change my risk, spread of my PCa.

Generally, SRT earlier is better...here's my question:

When you say SRT, do you mean to the prostate bed only or are you including whole PLN and perhaps short term ADT, say six-twelve months. I ask, because SRT to the prostate bed only is generally not the standard of care for BCR today. I would read through the NCCN guidelines...

You indicate your pathology report said GS 3+4 which puts you in Grade Group 2..

In recent years, healthcare providers have realized that the Gleason score might not always be the best way to grade PCa. For instance, not all cancers with a GS of 7 are the same. Cancers with more grade 3 areas (3 + 4 = 7 GS) are less likely to grow and spread than cancers with more grade 4 areas (4 + 3 = 7 GS). Likewise, Gleason score 8 cancers are less likely to grow and spread than cancers with a GS of 9 or 10.
Based on these differences, healthcare providers have started to use a newer system that breaks up PCas into 5 grade groups:
• Grade group 1 = Gleason 6 (or less)
• Grade group 2 = Gleason 3 + 4 = 7
• Grade group 3 = Gleason 4 + 3 = 7
• Grade group 4 = Gleason 8
• Grade group 5 = Gleason 9 or 10

As to your urologist statement that you are young and may experience radiation toxicity, he is not wrong, but...I'm going to throw the BS penalty flag here. Attached is my clinical history. I've had radiation treatment three different times over my 10 years, 69 total treatments, nada...why, advances in imagery, treatment planning software and delivery. I've said this before I've sat down with my radiologist, the same one during my journey, she's shown me the software, the hardware, it's pretty impressive.

ADT is not "putting a bandaid on things," do a literature search on micro-metastatic PCa, just because imaging doesn't see it, doesn't mean it's not there!

There are divergent views on curing PCa once it's spread, some say it's possible, others say no, you manage it as a chronic disease. In my case, definitely the latter. When I had my BCR in December 2015, my urologist and radiologist wanted to do SRT to the prostate bed, the SOC. I asked about data emerging from CTs and from Mayo that more often than not, the PCa had spread beyond the prostate bed after surgery and was in the PLNs, therefore SRT should include the PLNs and shorty term ADT. I said given my GS and short time to BCR, should we do that, their answer, no, there wasn't long term data to support that. Well, 90 days after competing my SRT, my radiologist turnd from her screen after seeing my PSA results and said "that didn't work, what do you want to do next! As you can see from my chart, it was in the PLNs, we just didn't have the imaging at that time to see it, today we do! I assure you, that was the last time I let my medical team talk me out of a treatment decision!

So, yes, your PSA does seem to indicate BCR, a treatment decision may be needed, question is, when to pull the trigger and with what. The good news, you have choices, many, the "not so good news, you have choices, many...!

Here's a interesting and possibly relevant study - https://www.urotoday.com/conference-highlights/asco-gu-2023/asco-gu-2023-prostate-cancer/142438-asco-gu-2023-tps402-phase-iii-study-of-local-or-systemic-therapy-intensification-directed-by-pet-in-prostate-cancer-patients-with-post-prostatectomy-biochemical-recurrence-indicate-ec?utm_source=newsletter_12613&utm_medium=email&utm_campaign=design-access-and-consensus-criteria-in-gu-clinical-trials

Kevin