High-dose rate iridium-192 brachytherapy and external beam radiation therapy for prostate cancer with or without androgen ablation.

Aim: To report the results of our feasibility study incorporating iridium-192 high-dose-rate (HDR) afterloading brachytherapy and external beam radiation therapy (EBRT) for the treatment of prostate carcinoma and to assess the role of androgen ablation in conjunction with this treatment option.

Methods: From July 2000 to June 2002, 42 patients with clinically localized or locally extensive prostate carcinoma were treated with HDR iridium-192 brachytherapy and EBRT with or without androgen ablation. The median follow up was 16.5 months.

Results: The technique of HDR brachytherapy and EBRT proved to be feasible with acceptable morbidities. Continuous prostate-specific antigen (PSA) reduction was noted in all patients and no PSA failure was noted during follow up. Within 1 year, the decline of PSA nadir values less than 1 ng/mL was faster in patients with the addition of androgen blockade (P = 0.001). However, within 1 year, PSA nadir values less than 1.0 ng/mL can be achieved in all patients whose initial PSA is less than 20 ng/mL, with or without hormone blockade.

Conclusions: The need for hormonal therapy in favorable-risk brachytherapy patients (PSA < 20 ng/mL) might be less than the need for intermediate- or high-risk patients. The use of hormonal therapy in intermediate-risk patients (PSA >/= 20 ng/mL) treated with HDR brachytherapy and pelvic EBRT is appealing, considering the favorable results. High dose rate brachytherapy appears to be an effective treatment for clinically localized and locally extensive prostate cancer, with minimal morbidity.