Figure 3.

Example dose-volume histogram (DVH) demonstrating the fraction-by-fraction delivered gross tumor volume (GTV) dose using online adaptation for a typical patient with an ultracentral right upper lobe lung metastasis. Proximity to the heart required plan adaptation for multiple fractions, with variable adaptive GTV dose escalation and de-escalation, but cumulative GTV dose remained at goal. Dose from adaptive fractions (red lines) and the projected dose from the original simulation plan that would have been delivered by nonadaptive fractions (blue dashed lines) are shown for comparison, as are the cumulative adaptive versus nonadaptive dose. The treatment fraction depicted here exemplifies the typical cumulative dose profile for all patients included in the study. (A color version of this figure is available at https://dx.doi.org/10.1016/j.adro.2018.10.003.)