My profile shows more details but in summary I have Gleason 4+4 prostate cancer, diagnosed 7/15 and treated with radical prostatectomy followed by pelvic radiation and 18 months of Lupron. After about 18 months off treatment new spread to sacral bone was found on choline 11 PET scan. This was radiated and I received about 22 months of Lupron, with Xtandi added for about 14 months. This ended about 3/21. PSA every 3 months remained undetectable until 6/22 when it began to rise, finally to 1.44 in 10/22 at which time a new, different spot was found on choline scan in the sacral bone. Beginning about 3 weeks after that PSA I received more radiation to that site. A few days ago my PSA was 1.33; this is about 4 weeks after the radiation ended. I remain off Lupron or other ADT.
My hope is that this is the last spot of cancer. I know that's not the most likely situation but a guy can hope! The plan at this time is repeat PSA and scan in mid January.
Here's my question: I understand that most cancer cells don't immediately die from radiation. but only when they try to divide. Does anyone have any ideas about how fast the PSA should decline after RT if the sacral spot is the last cancer? I had hoped that it would at least be significantly lower by now.
Help with managing side effects from radiation therapy.
Post-Salvage Radiation GI side effects?
Radiation side effects
Cancer Recurrence After Radiation/Chemo
Radiation after effects 
