newtothegroup, you'll be quite valuable to any clinical trial for metastic prostate cancer. And that value will be passed on to others in time.
The doctor who treated you for the last year should have ordered an MRI a year ago. It would be good to find a new internal medicine physician. You may not want to change urologists, but I suggest you might be better served. Most important now is to research the clinicals. I'm hoping you will get your records and send them out for second opinions on the best trial for you. It may be easier to keep your present doctor. And sometimes that's all we can manage. Somatic testing of the tumor looks at the somatic mutations in the tumor itself. Knowing this can tell you the chemotherapeutic agent most likely to destroy your specific tumor. The testing is done on the biopsy samples already obtained. You only have to request the testing and then wait.
https://www.cancer.gov/research/participate/clinical-trials/disease/prostate-cancer/treatment
Bless your search.

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