Use of percutaneous transperineal 198Au seeds to treat recurrent prostate adenocarcinoma after failure of definitive radiotherapy.

Patients who fail external radiation therapy for prostatic cancer pose a therapeutic challenge. No further external radiation treatment can be delivered safely to the local lesion, although some patients are candidates for salvage surgery. In this study, 31 patients who failed prior external beam radiotherapy received percutaneous transperineal placement of gold seeds (198Au). Initial prostate volume was 17.7 cc and decreased to 10 cc 24 months after 198Au implantation. Of 15 patients biopsied at 12 months after treatment, 4 (27%) were positive, 6 (40%) were negative, and 5 (33%) showed prostate cancer with radiation changes. Two of three patients have died of prostate cancer, with an overall 5-year estimated survival of 67%. Interstitial brachytherapy was found to be an additional well-tolerated treatment modality in this group of 31 patients.