RecruitingDrug trialHSV-tk + Valacyclovir Therapy in Combination With Brachytherapy for Recurrent Prostate CancerThe purpose of this study is to conduct a Phase I - II clinical trial to extend preclinical studies involving in situ HSV-tk + Valacyclovir gene therapy in combination with brachytherapy for recurrent prostate cancer. This will provide a novel therapeutic approach to prostate cancer and hopefully impact on the development of metastatic disease and the control of preexisting metastasis.