Short-term results of computerized tomographic-based transperineal iodine-125 prostate implantation

There has recently been a resurgence of interest in iodine-125 (I-125) prostate implantation for early stage carcinoma due to the introduction of transrectal ultrasonography (TRUS) or computerized-tomographic (CT)-based transperineal techniques. The present study details initial tumor response and morbidity of CT-based transperineal prostate implantation. Forty-two patients with clinical stage T1 or T2 prostatic carcinoma had CT-planned transperineal I-125 implantation of the prostate and have been followed for 6–47 months (median: 19 months). Thirty-eight patients had an elevated PSA before implantation (>4.0 ng/ml). A total of 35–73 mCi I-125 was implanted (median: 48 mCi). At 1 year after implantation, 84% of 29 palpable tumors were no longer palpable. Of 38 patients with an elevated prostate specific antigen (PSA) prior to implantation, 98% returned to normal within 12 months of treatment. In 74% of patients, the PSA value fell to below 1.0 ng/ml within 12 months of implantation. Of 25 patients who were sexually potent prior to implantation, 80% remained potent at 3 years. Four patients developed radiation-induced rectal ulcerations 9–19 months following implantation. Of those four patients, one has healed spontaneously, two are improving, and one was diagnosed only 1 month prior to this report. Initial tumor response to I-125 implantation is comparable to that achieved with external beam irradiation, with acceptable morbidity and high preservation of sexual potency. With adjustments in technique, morbidity is expected to be lower in the future. © 1993 Wiley-Liss, Inc.