High dose-rate brachytherapy of prostate cancer utilising Iridium-192 after-loading technique: technical and methodological aspects.

The aim of this study was to focus on certain characteristic problems associated with Iridium-192 high dose-rate brachytherapy (Ir-192 HDR-BT) in combination with external beam radiation therapy (EBRT) in the treatment of patients with localised prostate cancer. Over a period of 16 years, >2,000 patients with prostate cancer have been treated in Sweden with a combination of two fractions of 10 Gy Ir-192 HDR-BT and 50 Gy of fractionated EBRT. Although this treatment is usually well tolerated, there are biological and technical factors to be considered before and during the treatment of the patient to avoid side effects or under-treatment of the target volume. Some of the problems facing the doctors are transducer stability, needle deviation, target definition, target motion, pubic arch interference, concomitant diseases and tolerance doses for different organs at risk. These problems are discussed and possible solutions are presented in this study.