A prospective trial of volumetric intensity-modulated arc therapy vs conventional intensity modulated radiation therapy in advanced head and neck cancer

Figure 1 PTV_HD dose volume histogram for all volumetric intensity-modulated arc therapy plans (blue), all intensity modulated radiation therapy plans (red). The mean intensity modulated radiation therapy dose volume histogram (DVH) (blue dashed line) is plotted on the same axis as the mean volumetric intensity-modulated arc therapy DVH (red solid line). PTV: Planning target volume; VMAT: Volumetric modulated arc therapy; IMRT: Intensity-modulated radiation therapy.

Figure 2 Example plan evaluation of intensity modulated radiation therapy vs volumetric intensity-modulated arc therapy for patient No. 18. The volumetric intensity-modulated arc therapy plan (right) had dose that wrapped around the spinal cord despite an avoidance structure. The corresponding intensity modulated radiation therapy plan (left) did not.