I was on AS for five years. Had a biopsy twice and annual scans. My urologist assured me that things were stable. Then they weren't.
Scans once a year are sometimes not enough. My cancer progressed from one year to the next to the point where a prostatectomy become somewhat of an emergency. Unfortunately that all happened when my doctor had a scheduled family vacation and an already backed up patient load, so a couple of months went by before surgery was scheduled. And then the customary three month time span after the procedure before checking my PSA allowed the cancer that had metastasized to get a foot hold.
After having completed chemo, ADT and radiation therapies over these past two years I'm stable at the moment but it's a waiting game now to see when it comes back.
My biggest mistake during the period I was under AS was that I was somewhat apathetic about the disease and treatment options. I let my doctor make all of the decisions. I trusted that everything would just be fine.
I should have started my research early on when the disease was first detected and I should have sought out second and third opinions.
Would things have been different had I done more research? It's hard to say but at least I would have been more in charge of the process and perhaps taken earlier steps toward treatment.