An analysis of knowledge-based planning for stereotactic body radiation therapy of the spine

Publication date: Available online 2 March 2017
Source:Practical Radiation Oncology
Author(s): Joseph J. Foy, Robin Marsh, Randall K. Ten Haken, Kelly C. Younge, Matthew Schipper, Yilun Sun, Dawn Owen, Martha M. Matuszak
PurposePlanning for spine stereotactic body radiation therapy (SBRT) is time consuming and differences in planner experience and technique result in discrepancies in plan quality between facilities. Here, knowledge-based planning (KBP) is analyzed in order to determine if it may be effective in improving the quality and efficiency of spine SBRT planning.MethodsThirty-eight spine SBRT cases were collected from the XXX database and inverse planned to deliver three 10-Gy fractions to the PTV. These plans were used to train a knowledge-based model (Model A) using RapidPlan (Varian Medical Systems). The model was evaluated for outliers and validated in ten independent cases. Each of these cases was manually planned in order to compare the quality of the model-generated plans with the manual plans. In order to further test the robustness of the software, two additional models (Models B and C) were created with intentional outliers due to inconsistent contouring.ResultsUsing Models A, B, and C, all 10 generated plans met all dose objectives for modeled organs-at-risk (OARs) (spinal cord, cord PRV, and esophagus) without user intervention. The target coverage and OAR dose sparing was improved or equivalent to manual planning by an expert dosimetrist. However, manually created plans typically required 1–1.5hours to produce and model-generated plans required only 10–15minutes with minimal human intervention in order to meet all dose objectives.ConclusionThe plans produced by RapidPlan were found to be of improved or similar clinical quality as the manually created plans in terms of normal tissue objectives and PTV dose coverage and could be produced in a fraction of the time. RapidPlan is a robust technique that can improve planning efficiency in spine SBRT while maintaining or potentially improving plan quality and standardization across planners and centers.



http://ift.tt/2lWC56Z