Welcome to the place.
The term you are looking for is "oligometastatic", there have been a couple of studies done, notably the Oriole study. If you have only a couple of mets and they can be irradiated, you have a shot at kicking the can down the road some more, perhaps even a cure.
Oriole study https://clinicaltrials.gov/ct2/show/nct02680587
Search for "oligometastatic prostate cancer treatments" will likely give you some more information. I am in the process of becoming the first such patient to be treated at my local hospitals radiation oncology dept. for 2 pelvic lymph node mets.