One year PO and now it seems I'm Stage 4 :-(

Hi, It's been a while since I posted on here so here goes a quick review of my past and my latest issue.
I had been under active surveillance for almost 4 years since 2021 with PSA peaking at 5.8 and then slowly decreasing PSA numbers and I had biopsy Gleason scores of 3+3=6 back in 2021. I was on Finestaride and Flowmax during the AS. Then in Oct. 2024 my PSA jumped 30% from 3.6 to 4.6 and they did another biopsy in Jan 2025 and I had Gleason scores of several cores at 4 + 3 = 7 (Grade group 3) and one at 4+4=8/10, (Grade group 4). My first PET scan in late February 2025 showed no spread. and genetic testing in 2021 said not likely to progress. I had what was supposed to be routine prostate removal via Da Vinci method last May. The surgeon said he had to get fairly aggressive with the right side whatever that meant and he spotted a cyst on my colon and made the decision to remove it. The cyst and lymph nodes were clear. My final prostate pathology after surgery was T3a. I had gotten two good PSA tests of < 0.1 in August and November. Come Feb. I was at 0.2 and 4 weeks later I was at 0.3. They ordered a PSMA PET-CT scan and found the it has metastasized into my right arm humerus bone, I had noticed some pain in that bone as far back as this past January but really didn't think anything about it.

The part of the PSMA-PET scan we are concerned with:
BONES & SOFT TISSUES: Sequelae of prior cervical spine ACDF and posterior instrument fixation with interbody disc spacer in the lower lumbar spine. Focal tracer uptake significantly above background associated with ill-defined sclerosis in the proximal right humeral diaphysis, compatible with metastasis (SUV max 28, image 82). Low level tracer uptake associated with the musculature of the right shoulder, favored reactive in etiology.

I don't personally know anyone that's had Prostate metastasis in the bone. I have my first visit with an oncologist next week with a Dr. Gregory Mitro and so far from asking around I've only heard good things about him. I have a short list of questions for him but I'm open to suggestions as to what to ask and what to expect. It's strange that it would travel all the way to an arm bone.

I really didn't expect to see myself in this position as I've always stayed on top of my health fairly well and have PSA tests going back over 10 years.