A Pilot Study of Dose dE-eScalaTion IN prostATe radIOtherapy usiNg the MRL
This study is a single centre feasibility trial. The trial will recruit men with intermediate risk localised prostate cancer who will all receive targeted dose (escalated/de-escalated dose directed by MRI) 5 fraction SBRT to the prostate. Trial Objectives are: 1. Primary To develop a 5 fraction de-escalated dose SBRT protocol capable of reducing side effects 2. Secondary * To assess levels of acute GU and GI toxicity (CTCAE) * To assess levels of late GU and GI toxicity (CTCAE) * To assess late sexual quality of life (expanded EPIC, IIEF-5) * To assess biochemical relapse-free survival at 2
• Men aged ≥18 years
• Histological confirmation of prostate adenocarcinoma requiring radical radiotherapy
• Gleason score 3+3, 3+4 or 4+3 (Grade groups 1, 2 or 3)
• MRI stage T2 or less (as staged by AJCC TNM 2018)
• MRI-visible tumour(s) of PIRADS v2 grade 3 or higher on T2 and diffusion-weighted imaging and/or dynamic contrast-enhanced imaging (multiparametric MRI or mpMRI) with concordant pathology
• Tumour nodule visible on MRI occupying \<50% of prostate on any axial slice and \<50% prostate volume
• PSA \<20 ng/ml prior to starting ADT (if applicable)
• Short course (\< 6 months) concurrent androgen deprivation therapy (antiandrogens or LHRH analogues) allowed though not mandated as per the discretion of the treating physician.
• WHO Performance status 0-2
• Ability of the participant understand and the willingness to sign a written informed consent form.
• Ability/willingness to comply with the patient reported outcome questionnaires schedule throughout the study.