Inclusion Criteria:  Histology confirmed prostate cancer Disease confined to the pelvis by imaging CT (CT scan of chest, abdomen and pelvis and bone scan or prostate specific membrane antigen positron emission tomography (PET-PSMA) if required according to local guidelines) Eastern Cooperative Oncology Group (ECOG) performance 0-1 Eligible for curative radiotherapy  Exclusion Criteria:  Metastasis beyond the pelvis Poor performance ECOG 2-4 Cannot follow directions to prepare for simulation (bladder filling and rectal emptying)