COMBINED TREATMENT WITH TEMPORARY SHORT-TERM HIGH-DOSE-RATE IR-192 BRACHYTHERAPY AND EXTERNAL-BEAM RADIOTHERAPY FOR IRRADIATION OF LOCALIZED PROSTATIC-CARCINOMA

Purpose: To evaluate the treatment outcome after radical radiotherapy of localized prostate cancer in 50 patients (38 patients with stage T1 -2 and 12 patients with stage T3) after a median follow-up time of 45 months (range 18-92 months). Methods: The treatment was given by combi nation of external beam radiotherapy (50 Gy) and brachytherapy (2 x 10 Gy). The brachytherapy was given using TRUS-guided percutaneously ins erted temporary needles with a high dose rate remote afterloading tech nique with Ir-192 as the radionuclide source. Three target definitions and dose levels inside the prostate gland were used. Local control wa s evaluated by digital octal examination, TRUS-guided biopsies and ser um PSA evaluations. Results: Clinical and biopsy verified local contro l was achieved in 48 of the 50 (96%) patients; for stage T1-2 in 37 of 38 (97%) patients and for stage T3 in 11 of 12 (92%) patients. A post treatment serum PSA level less than or equal to 1.0 ng/ml was seen in 42 (84%) patients, values from >1.0 to less than or equal to 2.0 ng/ml were seen in four (8%) patients and values exceeding 2.0 were seen in four (8%) patients. The late toxicity was minimal. Conclusion: The lo cal control results and the minimal toxicity after the combined radiot herapy treatment are promising. However, long term results are necessa ry before general use. (C) 1997 Elsevier Science Ireland Ltd.