RESUMO
AIM: The present retrospective study was to compare toxicity and survival outcomes in a group of low-risk PCa patients treated with either the preoperative planning technique (145â¯Gy) or the real-time IoP technique (160â¯Gy). BACKGROUND: The two most common permanent seed implantation techniques are preoperative planning (PP) with 145â¯Gy and real-time intraoperative planning (IoP) with 160â¯Gy. Although IoP has largely replaced PP at many centres in recent years, few studies have directly compared these two techniques. MATERIALS AND METHODS: Retrospective study of 408 patients with low-risk PCa treated with permanent seed implant brachytherapy at our institution between October 2003 and December 2014. Of these, 187 patients were treated with PP at a dose of 145â¯Gy while 221 received real-time IoP with 160â¯Gy. RESULTS: At a median follow up of 90 months, 5- and 8-year rates of biochemical relapse-free survival (BRFS) were 94.8% and 86% with the IoP technique versus 90.8% and 83.9%, respectively, with PP. The maximum dose to the urethra was <217â¯Gy with both techniques. Despite the higher dose, IoP did not cause any significant increase in toxicity (pâ¯=â¯0.11). CONCLUSIONS: The present study shows that real-time intraoperative brachytherapy at a dose of 160â¯Gy yield better biochemical control than preoperative planning at 145â¯Gy. In addition, urinary toxicity did not increase, despite the dose escalation, probably because the dose constraints to the urethra were met despite the increased dose escalation. These findings support the use of real-time IoP.