Usefulness assessment of Stereotactic Body Radiation Therapy with Breathing Observation (RPM system) in Lung Cancer Patients Back Geum-Mun1, Na Soo-Kyung2,* 1Ph. D, Dept. of Radiation Oncology, Asan Medical Center, South Korea 2Professor, Dept. of Radiological Science, Gimcheon University *Corresponding Author: Soo-Kyung Na, Professor, Dept. of Radiological Science, Gimcheon University, Korea, Email: skna@gimcheon.ac.kr
Online published on 2 February, 2019. Abstract Background/Objectives The aim of this study is to evaluate the usefulness of the RPM system by comparative analysis in the reproducibility of tumor motion with respiration changes in patients undergoing SBRT. Method/Statistical analysis Twenty patients with respiratory gated radiation therapy and 20 patients without RGRT were divided into groups 1 and 2, and shoot 4-Dimensional Computed Tomography, Cone-Beam CTand Fluoroscopy In order to verify the stability of respiration during treatment. We set the reference interval of the respiration signal using Real-time Position Management(RPM) System(version 1.7.5, Varian, USA) for Group 2, and then, we counted the number of off-center values. Findings The differences between the average motions are measured by 4-D CT and CBCT the results are 1.0 mm, 1.1 mm, and 1.9 mm in the anteroposterior direction, the axial direction, and the lateral direction in Group 1. The mean axial difference between the 4-D CT and Fluoroscopy in the axial direction's result is 0.6 mm in group 1 and 2.3 mm in group 2. The difference in axial direction between CBCT and Fluoroscopy's result is 1.7 mm in group 1 and 1.4mm in group 2. In group 2, the number of treatments (20patients, single treatment, 15Gy) without not match with reference respiratory interval is 32 out of 80 times. The mean tumor movement value in all patients is less than 5 mm on average. In this study, the accuracy of the planned dose delivery during treatment can be improved by confirming the movement of the tumor with RPM system even in patients without RGRT. Improvements/Applications For improvement of this research we should consider another method for the patient who has very erratic breath. Top Keywords SBRT, RGRT, RPM system, Respiratory interval, 4-Dimensional Computed Tomography. Top |