Dose-Dependent CT Number Changes in Both Tumor and Normal Lung Observed During Radiation Therapy for Lung Cancer

Abstract

Radiation induced anatomic changes, such as tumor regression, are common during the delivery of radiation therapy (RT) for lung cancer. Being able to measure such changes in irradiated lung tissue and/or tumor during the treatment delivery would enable adaptive RT. Based on daily diagnostic-quality CT images, we investigate the change of CT number as a measure of radiation response.