Feasibility and Toxicity of Degarelix for Prostate Downsizing Prior to Permanent Seed Prostate Brachytherapy

This study will investigate the efficacy of Degarelix, a Luteinizing Hormone Releasing Hormone (LHRH) antagonist, to reduce prostate volume prior to permanent seed prostate brachytherapy. There are 2 eligible populations of men, all of whom will have selected brachytherapy as their treatment of choice for their prostate cancer. Either they have an enlarged prostate that requires size reduction to render brachytherapy technically feasible, or they require androgen ablation in conjunction with brachytherapy for optimal tumor control. The hypothesis is that Degarelix will provide \> 30% volume reduction by 3 months in \> 30% of men.

All men will have a baseline transrectal ultrasound for brachytherapy planning that has demonstrated an enlarged prostate with or without pubic arch obstruction. After signing the informed consent document they will have a loading dose of 240 mg Degarelix and then monthly maintenance dose injections of 80 mg until such time as sufficient prostate reduction has occured (2-3 months) or they complete the 6 months of required androgen ablation for their disease status.