The Effect of a Contrast Agent on Proton Beam Range in Radiotherapy Planning Using Computed Tomography for Patients With Locoregionally Advanced Lung Cancer

If CA-enhanced CT images are used for radiotherapy planning using a proton beam for the treatment of lung cancer, our results suggest that the HU values of the heart and great vessels should be replaced by the average HU values of soft tissue to avoid discrepancies between planned and delivered doses.