Combined treatment with temporary short-term high dose rate Iridium-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 combination of external beam radiotherapy (50 Gy) and brachytherapy (2 x 10 Gy). The brachytherapy was given using TRUS-guided percutaneously inserted temporary needles with a high dose rate remote afterloading technique with Ir-192 as the radionuclide source. Three target definitions and dose levels inside the prostate gland were used. Local control was evaluated by digital octal examination, TRUS-guided biopsies and serum PSA evaluations. Results: Clinical and biopsy verified local control 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 posttreatment 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 local control results and the minimal toxicity after the combined radiotherapy treatment are promising. However, long term results are necessary before general use. (C) 1997 Elsevier Science Ireland Ltd.