ESTRO 2020 Abstract book

S860 ESTRO 2020

Quantitative improvements were observed between the KB models and the reference plans, particularly for heart and spinal canal doses. As shown in Tab. 1, the models reduce the heart mean dose of about 0.5 Gy and the V20 of 1.2 Gy on average. Moreover, the maximum dose for the spinal canal is about 1.5 Gy less on average. The 3% of 270 analyzed dose-volume objectives in the clinical plans failed to reach the optimal constraints, while the respective KB plans succeeded. In 3 cases out of 18 evaluation data set plans, the KB plan failed at least one of the dose-volume constraint compared to the delivered plan, but with a mean difference less than 5%. The DVH comparisons between clinical plans and the two models for the best and the worst cases are plotted in Fig. 1. Model B results in a better OAR sparing in the 52% of the values compared to model A.