Figure 1.

Demonstration of ART intents and relative dosimetric on OARs and tumor. This example shows the initial treatment plan on CT and simulated adapted plans on an MR-linac image for a patient with primary stage T3N2 human papilloma virus positive squamous cell carcinoma of the base of tongue prescribed 70 Gy in 33 fractions. In silico simulated adapted plans were generated with the various ART intents on the MR-linac image from fraction 22. Graphs show dose volume histograms for the gross target volume (GTV) (green), ipsilateral parotid gland (blue), and contralateral parotid gland (red) with solid lines for the adaptive plan and dotted lines for the reference plan. In the column showing the DVH parameters relative to the reference plan, mean dose was used for the parotid glands and D_95% for the PTV. For the ART_Reduco plan, reduced GTV and PTVs were artificially created by applying a uniform reduction of 1cm in all directions for each structure.