Focal Brachytherapy (Interventional Radiotherapy) and IMRT

Focal radiotherapy, either external beam radiotherapy (ERT) or brachytherapy (BT, interventional radiotherapy—IRT), is one of the possible therapeutic strategies for partial organ treatment in prostate cancer. Because of the existence of multiple focal therapy technologies, an adequate and personalized treatment decision needs the interdisciplinary team discussion with inclusion of an adequate IRT expert. In particular, the argument raised in favour of focal therapy was that the proportion of unifocal tumours was found to be in patients undergoing radical prostatectomy between 13% and 38%; more specifically when considering low risk patients most of them had higher primary Gleason grades contained within the DIL. Regarding radiotherapy methods, the importance to accurately identify the DIL, with special focus on the three dimensional location and its proximity to the critical anatomical structures, relies on the clinical evidence that usually the site of recurrence, after radiotherapy, occurs within the DIL. This point is of paramount relevance in fact there is a clinical relationship between the dose delivered to the DIL and the actual risk of relapse with patients receiving higher doses having a lower risk of recurrence. In addition, it has been demonstrated that most satellite lesions do not negatively affect the overall survival.