Unfortunately there are a lot of grey areas with PC diagnosis, which includes the various imaging tests which do not always provide the black and white answers desired.
The tests are done to help determine whether the PC is still confined. No one knows how quickly it might spread, as it sometimes remains indolent for considerable time.
Full diagnosis, Gleason scores, % of cancer in biopsy cores, rate of PSA change is information which can provide a better insight.
Hormone treatment is believed to improve the effectiveness of radiation treatment. It is aimed at reducing testosterone levels and can shrink the prostate.
Hormone therapy can slow the advance of PC, sometimes for a prolonged time, which is why it is also used longer term in high risk situations.