Salvage radiation decision: with or without hormone therapy?

My prostate cancer doesn't produce PSMA. Had the PSMA pet, nothing lite up. If i go with radiation to the prostate bed, how can i be assured there is not cancer elsewhere. What test is there for this situation?

For prostate cancers that don’t express PSMA, you go back to the older Axumin (F18-Fluciclovine) PET/CT scan or C11 Choline PET/CT scan (that Mayo Clinic uses). In the absence of PSMA, those are preferred.

Dr. Kwon (of Mayo Clinic) indicates that only 1/3 of men who have recurrence following prostatectomy have recurrence only in the prostate bed, and that they should not get salvage radiation there unless they’re absolutely certain of the location of recurrence. He says to first confirm where the recurrence is. (See Dr. Kwon’s presentation about recurrence: https://youtu.be/Q2joD360_pI)

One other scan that works well to see cancer that doesn’t produce PSMA Is the FDG scan. It uses Fluorodeoxyglucose and it can identify the presence of cancerous tumors, determine their spread (metastasis), and monitor the effectiveness of cancer treatment.

I am continually told that adding hormone therapy before and after radiation increases the effectiveness of the radiation. The differing opinions I receive are more around the duration of ADT and have ranged from 4 months to two years. I think two years may be outdated and 18 months is sufficient for those choosing to be safer on the longer end. Personally, I would get ADT if I was getting radiation again.

The duration of ADT depends on the aggressiveness of the disease and any other risk factors. NCCN Guidelines call for ADT duration of:
> Unfavorable intermediate: 4-6 months
> High or Very-High Risk: 12-36 months
Adding hormone therapy lowers testosterone, which removes the “food” prostate cancers need. This starves/weakens the prostate cancer cells, making them more susceptible to DNA damage from radiation (and also weakens their repair mechanisms),

The length that you take hormone Therapy is based on your Gleason score 1st and your case second.

If you have a Gleason 7 Six months of hormone therapy is recommended

If you have a Gleason 8 18 months of hormone therapy is recommended

If you have a Gleason 9 24 months of hormone therapy is recommended

These numbers can change based on your cancer. If you have Gleason 8, but a very mild case, they may not keep you on 18 months if your PSA stays undetectable. The same is true for the other groups, But it does make sense to Keep to the standards for most people because it allows them to have the best overall survival.

My prostate cancer was already in the bone when my PSA was 3.6 or so. As far as hormones, they don't seem to bother me too much. Minor hot flashes and a tendency to stop at all garage sales and more viewing of the Halmark channel. I've noticed that my muscle mass is going down, so I need to get more protein and workout more. My motivation has gone down some.
So, for me it's a no brainer to take the hormones as I deal with them relatively well and the outcome appears to be better. I'll do anything they tell me to have a better chance at life. I guess I'm kind of selfish.
BTW, I'm going to Sloan Kettering for my needs.
Good luck whatever you choose to do!!!!
Dave

Like your attitude!!

Thank you to everyone who responded to my initial question about SRT with/without ADT. I really appreciated all your input!

I did have an FDG-PET scan at Mayo in July which showed no activity. My Oncologist advised I wait 6 months and do another PSA test. In November my PSA was .3. I had another PSMA-PET which again showed no activity. After consulting with my Oncologist and Radiation Oncologist, I decided to do SRT without ADT. I’ve completed 4 of 38 fractions. I’m hopeful at the end of my treatment my PSA will be undetectable for several years. If it does rise again, I’m hopeful scanning and treatment options will have improved. It was frustrating that the scans showed no evidence of cancer, while my PSA continued to increase. But based on comments from this group, that scenario seems fairly common. My doctors all recommended SRT (prostate bed + lymph nodes) but they were split on ADT vs. no ADT. I’ll send another update with my PSA test results after treatment.
Wishing everyone a Merry Christmas and Happy New Year!

Chuck, I completed 38 fractions of salvage IMRT on November 18 (no ADT). Hit the prostate bed as well as the pelvic lymph nodes, prophylactically. First follow up PSA will be in mid February 2026.

I had a RARP in 2015. Gleason 3+4, one positive margin, Prolaris score 1.7 with a 53% chance on BCR at ten years.

I went ten years with undetectable (< 0.1) PSA. Then in June 2025 my PSA hit 0.11 (Quest). A repeat test a few days later yielded the same result, ruling out lab error. Then, a DRE detected a palpable nodule in the prostate bed. That precipitated a PSMA PET scan and MRI with contrast, both confirming that the nodule was cancerous. No scanning evidence for pelvic lymph node involvement, nor distant mets.

Two oncologists recommended short-term ADT with the IMRT, one did not. I weighed the pros and cons for my case. The barely detectable PSA and ten years to recurrence were strongly in my favor. Three months after my PSA hit 0.11, it remained unchanged, and actually an usPSA test from Labcorp yielded 0.094. Curious to think that if I had that test back in June, I likely would have been told to come back in a year, rather than getting scanned and diagnosed with recurrent PCa.

Anyway, I decided against the ADT, concluding that the benefits did not outweigh the risks for me. Gray area decision. Someone else with different concerns/priorities may taken a different path.

Another oddity of my case was that despite the low PSA, the nodule lit up on the PSMA PET scan with a max SUV of 13.3. Data don’t always align, and sometimes they defy conventional wisdom, but I think the important result was that the nodule lit up and nothing else did. My urologist concurred.

I posted a long summary of my IMRT experience if you haven’t seen it: https://connect.mayoclinic.org/interaction/discussion/68361/reactions/listview/

I will add that post-RT, I have had a bunch of rashes and skin irritations in different parts of my body. Bothersome and unsightly, but my dermatologist saw nothing serious. Probably opportunistic fungal or viral flare ups because my immune system was whacked out. They seem to be resolving now. I didn’t think that my RT fatigue was real bad, but now in late December, I am feeling pretty much back to normal energy levels (am 73 now). Looking back, I was more wiped out by the RT than I realized. Getting back to full energy capacity took more than a couple weeks. Feels good to just be living a normal life again, including not being on the “full bladder/empty rectum” diet.

Hope your RT goes well.

Here’s to a better 2026 with ultra low PSA! I’m sure we will be comparing and sharing PSA scores and progress in the new year.

Mel