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

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.

Inclusion criteria

• Histologic diagnosis of prostate cancer
• Favorable risk disease (cT1 or T2a, Gleason score (GS) 6, and Prostate Specific Antigen (PSA) < 10 ng/mL)
• Low-tier intermediate risk disease (cT2c,GS=6,and PSA 10-15 ng/mL, OR GS=7 and PSA < 10 ng/mL)
• Intermediate risk disease AND androgen deprivation therapy recommended by the treating physician for oncologic reasons such as (≥ 50% positive biopsy cores,cT2c,PSA 15-20 ng/mL,GS=7)
• Patient requires baseline planning trans-rectal ultrasound for the purposes of prostate brachytherapy, showing prostate volume > 40 mL and pubic arch interference (not required for those requiring androgen ablation for oncologic reasons)

Exclusion criteria

• castrate serum testosterone level
• previous or concurrent pelvic radiotherapy
• unable to give written informed consent
• contraindications to permanent seed prostate brachytherapy or to androgen deprivation therapy
• prior treatment for prostate cancer
• prior trans-urethral resection of the prostate
• previous therapy with a 5-α reductase inhibitor, anti-androgen agent, or LHRH agonist
• previous therapy with degarelix