Metastatic disease to the bone is a bad prognostic event and implies advanced prostate cancer. Complete androgen blockade (an LHRH agent as well as an anti-androgen such as Casodex) is needed to best control the disease. Unfortunately, over time patients with advanced disease tend to stop responding to these therapies. At that time the PSA will start to rise and therapy will be changed. Due to your advanced disease and relatively young age, it my be a reasonable approach to look into clinical research trials that are ongoing which may offer other suitable alternatives.