Volumetric image-guidance: does routine usage prompt adaptive re-planning? An institutional review.

Purpose: To investigate how the use of volumetric image-guidance using an on-board cone-beam computed tomography (CBCT) system impacts on the frequency of adaptive re-planning.

Material And Methods: Treatment courses of 146 patients who have undergone a course of external beam radiation therapy (EBRT) using volumetric CBCT image-guidance were analyzed. Target locations included the brain, head and neck, chest, abdomen, as well as prostate and non-prostate pelvis.