Prostate cancer post-prostatectomy radiotherapy: CT vs MRI for vesico-urethral anastomosis target delineation

Abstract

Background Vesico-urethral anastomosis (VUA) is critical to the clinical target volume (CTV) in post-prostatectomy radiotherapy (PPRT), as it is the commonest site of recurrence. Typically, this is performed on a CT alone but guidelines recommend MRI. Objective To evaluate the VUA spatial differences between CT (ctVUA) and MRI (mrVUA) and analyse its impact on the CT defined CTV (ctCTV) as recommended by published guidelines. Materials and methods We identified 34 patients with a co-registered simulation CT and T2 weighted MRI. The VUA was located on CT and MRI whilst blinded to the opposing scan. The differences were analysed using Wilcoxon's Signed Rank Test. The mrVUA coverage was investi..