Figure 1.

Mediastinal and abdominal patient examples showing in color wash the distribution of ≥95% of the prescribed dose in the reference situation (left), scheduled plan (middle), and adapted plan (right) under treatment. In the mediastinal example (panel A), reduced esophageal dilatation under treatment (session 13) results in smaller target volumes and therefore less dose to organs at risk in the adapted plan compared to the scheduled plan. Mean heart dose was 17.4, 20.2, and 17.4 Gy, and mean lung V_20Gy was 16.8%, 17.3%, and 12.6% for the reference, scheduled, and adapted plan, respectively. In the abdominal example (panel B, session 25), changes in stomach anatomy under treatment lead to suboptimal coverage of target volumes with the scheduled plan. D99%_PTV was 96.1%, 78.6%, and 95.5%, and D95%_PTV was 98.3%, 94.2%, and 98.1% for the reference, scheduled, and adapted plans, respectively. Note that, according to contouring guidelines, the clinical target volume (CTV) (orange outline) extends up to 1 cm into the lungs (blue), and 0.5 cm into the heart (white) and liver (brown) in both the reference and adapted situations.