Conventional margins not sufficient for post-prostatectomy prostate bed coverage: An analysis of 477 cone-beam computed tomography scans

Evaluating the accuracy of the XVI dual registration tool compared with manual soft tissue matching to localise tumour volumes for post‐prostatectomy patients receiving radiotherapy

“…Where clinically indicated, superior portions of the CTV could be omitted from the mask so their position does not overly influence the ‘best fit’ approach when variations in bladder and rectal filling exist. In addition, differential PTV margins are required to take into account the increased variability seen in the superior volumes as discovered by the Gill et al . study.…”

Ultrasound versus Cone-beam CT image-guided radiotherapy for prostate and post-prostatectomy pretreatment localization

“…However, whereas the systematic shifts were more pronounced in the posterior direction for prostate patients, for post-prostatectomy patients, there was a trend to have larger differences in the SI direction, with more pronounced shifts in the inferior direction. Two assumptions can explain this observation: first, the difficulty to accurately localize the vesico-ureteric anastomosis on CBCT images [24]; second, the RPV is only defined in the inferior direction on US images, and arbitrarily truncated in the superior direction. Thus, US images registration only relies on one boundary instead of 2 for the other directions (Fig.…”

Superior target volume and organ stability with the use of endorectal balloons in post‐prostatectomy radiotherapy

“…This highlights an issue with current contouring guidelines in general, that a uniform posterior PTV margin is not sufficient in the post‐prostatectomy setting regardless of treatment with or without an ERB. The concept of differential superior and inferior CTV expansion margins has been proposed in the studies of Gill et al . and Bell et al .…”