@susanocl
I had salvage radiation 3 1/2 years after my prostatectomy when my PSA hit .2. I had no side effects from that radiation, Six years later, I did have incontinence problems, but that’s probably about surgery and radiation. I had 8+ weeks of radiation and the lower dose allows most to avoid the urinary issues.. if they do it in a shorter term and give more radiation that does cause some urinary irritation for many people, flowmax Usually resolve the problem.

After a prostatectomy, a PSA should become undetectable. The fact that your husband didn’t is a major issue. Something needs to be done soon.

After my surgery, I didn’t have any problems with incontinence, but getting an erection was impossible. That was 16 years ago so they didn’t spare the nerves back then.

I know dozens of people that had salvage radiation. I attend nine advanced prostate cancer meetings every month and hear from people that have had it done all the time.

Your husband really does need treatment and the salvage radiation will usually reduce the PSA to undetectable. It is not uncommon for the PSMA pet scan to find nothing, so they do the salvage radiation which treats the prostate bed and the lymph nodes in the area. That is the most likely place that there are mini metastasis that can’t be seen by scans. In my case, it gave me 2 1/2 years of undetectable PSA. That was 10 years ago. I’ve had three reoccurrences since but the drugs keep my PSA undetectable. My reoccurrences are due to a genetic problem I have BRCA2).

The American Society of clinical oncology (ASCO) sets standards for when salvage radiation should be done after surgery. Your husband is way beyond the maximum amount of time you should wait, That’s why your doctor feels it’s urgent. As high as your husband’s PSA is ADT is sort of essential to make sure that the radiation provides long-term results.

Here are the ASCO recommendations

From Ascopubs about what PSA to do salvage radiation.
≤0.2 ng/mL:
Starting at this level maximizes disease control and long-term survival. Patients treated at PSA < 0.2 ng/mL achieve higher rates of undetectable post-SRT PSA (56-70%) and improved 5-year progression-free survival (62.7-75%).
Delaying SRT beyond PSA ≥0.25 ng/mL increases mortality risk by ~50%.

0.2–0.5 ng/mL:
Still effective, particularly for patients with low-risk features (e.g., Gleason ≤7, slow PSA doubling time). The Journal of Clinical Oncology recommends SRT before PSA exceeds 0.25 ng/mL to preserve curative potential.

0.5–1.0 ng/mL:
Salvage radiation remains beneficial but may require combining with androgen deprivation therapy (ADT) for higher-risk cases.

This article discusses the above;
https://ascopost.com/news/march-2023/psa-level-at-time-of-salvage-radiation-therapy-after-radical-prostatectomy-and-risk-of-all-cause-mortality/

@susanocl Your original surgeon’s concern is telling; he would not be concerned if he knew that he had left some normal prostate tissue behind for nerve sparing purposes, which is commonly done.
And the PSA would not be as high as it is even if that were the case.
I had salvage radiation/ADT to the bed and nodes 5 yrs after surgery ((G4+3 unfavorable); your husband’s PCa is more aggressive so best to jump on it now before it has the chance to spread further. So far my SRT has been successful as measured by PSA. Will it stay that way - who knows?
But you can only take it one step at a time and hope for the best.
Phil

@susanocl Are you on any special diet? Are you still eating sugar? Are you doing any alternative treatment after surgery?