My limited and non-professional understanding is that in a case of aggressive prostate cancer, Gleason Grade 9, which has metastasized to the bones as your father's evidently has, there is no invasive treatment to be performed. Treatments at this stage are largely "palliative" ,that is aimed at retarding the progress of the disease, i.e.lupron, until the cancer becomes "hormone refractory" and then controlling its affects and pain. Medication can be given to minimize bone destruction and avoid fractures ,the biphosphonates e.g. Aredia,,Bonefos, Zometa. Strontium 89, a radioisotope can be given to curtail and prevent bone metatstases. Pain medication can be given beginning with Nsaids and eventully morphine if the pain becomes severe. Your father's oncologist should be able to advise and prescribe these drugs and second opinions sought if you don't feel his primary oncologist is doing all that can or should be done to keep your father comfortable while at the same time retarding the progress of his cancer with the most advanced drugs and methods available.