Feasibility of permanent implants for prostate cancer after previous radiotherapy in the true pelvis.

Abstract

Permanent seed implantation was used in the management of primary and recurrent prostate cancer in patients who had been treated previously by radiotherapy of the true pelvis. Between 1993 and 1998 a total of 21 patients received an I-125 implant after radiotherapy for bladder cancer (two patients), anal cancer (one patient), seminoma (two patients) and prostate cancer (16 patients). Two seminoma and 10 prostate cancer patients were treated after earlier definitive external beam radiation therapy (EBRT), while the bladder and anal cancer were initially treated with EBRT plus iridium implantation. Six prostate cancer patients were initially treated by brachytherapy alone. The interval between the two treatments was longer in patients with radiotherapy for other malignancies than prostate cancer. After EBRT no serious late toxicity was observed. However, 1/6 patients who had two seed implants experienced serious complications, resulting in a vesico-rectal fistula. The permanent seed implantation with I-125 is feasible after previous radiotherapy in the prostate area. Also a second implant is possible, but may result in severe complications, depending on the initial dose and interval between the two treatments.