I am confused. Was my doctor correct?

So, I got Dx in 2018. No signs or symptoms felt great, did my annual physical exam. I was told my PSA was 81. They did a biopsy and had a Gleason of 10. BAD, yes, and the original oncologist said I had 1 to 3 years left and there was a metz on my lower backbone, as well as spots on lungs and lymph nodes were inflamed. This was in a small city, but luckily I came from Chicago, so I went there. The new Onc, looked at my chart and films and said the lungs were fine as well as L.N's. And the Metz on my backbone was extremely small, also I am riddled with arthritis from playing hockey for 35 years. So they decided it has metastasized. Went on Lupon and Zytiga. Still no signs or symptoms. Had a bone scan a year later and CT, the Metz was gone, no issues with the CT scan. Continued on. Just had new CT scan and Bone Scan, 3 and a half years later, and shows nothing. still the original Metz, nowhere to be seen, everything a-ok. STILL no signs or symptoms. SO my question, I continue on Lupon and Zytiga, did it ever metastasize? Or, as I suspected arthritis? Can I get my prostate ripped out for a cure? My Onc, is out for two weeks. My mind is wondering.