Fig. 3

Variation of respiration-related 3D displacements relative to week 1 (planning scan). Black lines represent patients with either ≥6 mm primary tumor motion range in a or ≥8 mm lymph node motion range in b in week 1. Patients with larger motion range on the initial week1 scan were more likely to have a > 5 mm change in motion range. Changes in respiratory motion in weeks 2–5 are normalized to the week 1motion range