Fig. 4

DVHs from the four planning approaches MFO_PTV, MFO_Rob, SFO_PTV and SFO_Rob (top to bottom) for the low- (blue) and high-risk CTV (red) of an example patient who received plan adaptation for 3 plans after the 5th and 23th fraction. The DVH from the nominal plan (solid line, shown in all plots for orientation) is complemented by the DVH bands from the 30 perturbed cumulative doses for robustness analysis considering the initial plan and (a) the nominal anatomy (\( {\overline{D}}_{pCT} \)), and (b) anatomy in the control CTs (\( {\overline{D}}_{cCT} \)). DVH from the unperturbed cumulative dose considering the anatomical changes and additional plan adaptation (c) are indicated by dashed and dotted lines. (*) indicates the fraction number of the control CT when the adaptation demand was found