@misc{oai:repo.qst.go.jp:00067987, author = {Koyama-Ito, Hiroko and et.al and 伊藤 浩子}, month = {Dec}, note = { This study reports and evaluates treatment planning including organ motion uncertainties for three-dimensional conformal therapy of lung cancer with respiration gated carbon ion broad beams. The distal margins were added by radiological path length. During treatment a patient is irradiated while the respiration signal from monitor placed on patient skin is close to end expiration phase of free breathing. Planning CT scans are taken gated with the same signal. To the CTV delineated on planning CT slices, margins for uncertainties in tumor movements are added based on fluoroscopy examinations typically 10 mm in cranial and 5 mm in caudal direction. The range compensator (RC) is designed for PTV that includes these margins under the assumption that the lung including tumor moves in cranial-caudal (CC) direction sliding along the chest wall. Dose distributions are calculated for different tumor locations. Within the model of lung motion, CTV dose coverage is observed although the irradiated lung volume increases in enhanced degree due to the low electron density of lung. The uncertainties in tumor motion are determined from clinical experience in fluoroscopy observations prior to irradiations. In order to reduce motion margins further, more accurate tumor position monitor is required. The effect of chest wall movement remains for future study with 4-D CT., 4th Shinji Takahashi Memorial International Workshop on 3D-CRT}, title = {INCORPORATING ORGAN MOTION UNCERTAINTIES INTO CARBON ION TREATMENT PLANNING}, year = {2004} }