External beam radiotherapy combined with androgen deprivation therapy is a standard treatment
option for localized prostate cancer. The current standard involves delivering radiotherapy
uniformly throughout the prostate gland in daily fractions, five days per week, for
approximately four weeks. In this study, radiotherapy will be delivered using an
ultra-hypofractionated approach in three larger fractions on alternating days over one week
Multiparametric magnetic resonance imaging will be used to guide focal dose escalation to
parts of the gland harboring tumor, which could potentially reduce the risk of cancer
recurrence compared to standard dose of radiotherapy. The aim of this study is to confirm
that this approach can be delivered safely, that is, with rates of urinary and bowel side
effects at 1 year of follow-up that are not significantly greater than the current standard.