I'm sorry to hear your news, and wish you the best in your treatment

For my own oligometastatic prostate cancer, I received external radiation to treat the metastasis (on my spine) as well as radiation to the prostate itself.

I don't know if external-beam radiation will be practical for your 5 metastases — that's on the borderline between what they consider "oligometastatic" (low volume) and polymetastatic (high volume) — so it's possible your medical team will offer you a different alternative for treating the metastases directly, such as chemotherapy (Doxecetol) or radioligand therapy (Pluvicto).

Both of those can target cancer inside your body, even if there are additional spots that haven't been detected yet.

I hope your next conversations with your medical team go well.