Fig. 3.

(a) The correlation between the biologically effective doses for the whole liver and the PTV. X and Y axes indicate the mean BED₂ for liver (Gy) and the proportion of PTV (circles; the solid line denotes the standard curve) and that of the overlap between the PTV and the liver (squares; the dashed line denotes the standard curve) in the whole liver, respectively. (b) The correlation between the potential liver dysfunctional volume (cm³) (Y axis) and the intersection volume between the PTV and the liver (cm³) (X axis). The circles (with the solid line denoting the standard curve) indicate the liver volumes that received a BED₂ of 50 Gy or greater. The squares (with the dashed line denoting the standard curve) indicate the liver volumes that received a BED₂ of 75 Gy or greater PTV = planning target volume, BED = biologically effective dose.