There are two schools of thought in the Oncology world developing for beginning treatment on BCR. One is PSA driven by reaching the established 2.0 PSA considered BCR threshold. The other emerging is the image driven treatment determined by it being seen on the PSMA-PET. This would typically exceed the PSA 2.0 level before being seen. The arguments include better focusing of radiation and results showing no detrimental effects on outcome. Similar to the studies that show awaiting initial treatment beginning up to six months post cancer diagnosis to determine what you are going to do has shown no overall change in outcomes. I think though that you might set your own upper PSA number if something is not showing on the PET that you pull the trigger. Clearly that number is what everyone wants to figure out. Definitely consult and you are in 2nd opinion territory again before deciding your course.