Endorectal Balloons in Postprostatectomy Radiation Therapy — Improved Stability of Clinical Target Volumes and Reduction of Geographical Miss

Abstract

The clinical target volume (CTV) in post-prostatectomy radiation therapy is bounded in part by the anterior rectal wall and posterior bladder wall. Therefore, deformation of these organs and hence the target volume can result in potential geographical miss. We report on the impact of endorectal balloons (ERB) on post-prostatectomy CTV stability, and quantify the minimum margin expansions required to avoid geographical miss.