HDR brachytherapy appears to be an ideal technique for dose escalation in PET/MRI+ (positron emission tomography) , small, well-defined IPBR that can be accessed and visualized through the perineal route with transrectal ultrasound (TRUS) guidance. Additionally, HDR brachytherapy can spare from high dose irradiation most of the vesicourethral anastomosis, the external urinary sphincter (EUS) and the penile bulb. This may be crucial in circular structures such as EUS that are particularly sensitive to whole-volume irradiation but tolerate well high small-volume doses provided that the rest of the EUS is spared.
In this study, HDR brachytherapy will be combined with external beam radiation and 6 months of androgen deprivation therapy to decrease the prostate bed volume irradiated at high-doses while increasing the radiation dose in the PET/MRI+ areas.