Lin Hui, Lu Heming, Shu Liuyang, Huang Huixian, Chen Huasheng, Chen Jiaxin, Cheng Jinjian, Pang Qiang, Peng Luxing, Gu Junzhao, Lu Zhiping
Department of Thoracic Surgery, People's Hospital of Guangxi Zhuang Autonomous Region, 6 Taoyuan Road, Nanning City, 530021, Guangxi, China.
J Radiat Res. 2014 May;55(3):583-8. doi: 10.1093/jrr/rrt145. Epub 2014 Jan 21.
This study sought to compare the differences in target volumes and dose distributions to the targets and organs at risk (OARs) between a four-dimensional computed tomography (4DCT)-based respiratory-gated intensity-modulated radiation therapy (IMRT) plan (PlanEOE) and a three-dimensional CT (3DCT)-based IMRT plan (Plan3D) in patients with non-small-cell lung cancer (NSCLC). For 17 patients with Stages I-III NSCLC, both 4DCT data and conventional 3DCT data were obtained. The Plan3D and PlanEOE were designed based on 3DCT data and 4DCT data, respectively. The displacements of the gross tumor volume (GTV) centroid were 0.13 ± 0.09 cm, 0.15 ± 0.1 cm, and 0.27 ± 0.27 cm in the right-left, anterior-posterior, and superior-inferior directions, respectively. The volume of the GTVEOE was 3.05 ± 5.17 cm(3) larger than that of the GTV3D. The volume of the PTV3D was 72.82 ± 48.65 cm(3) larger than that of the PTVEOE. There was no significant difference between the PTV3D and PTVEOE for V55.8, V60, V66 and the homogeneity index. The PTV3D had a lower target conformity index than the PTVEOE (P = 0.036). PlanEOE had a significantly lower lung V10, V20, V30, V40 and mean lung dose (MLD) than Plan3D. For the heart, PlanEOE had a significantly lower V30 and mean dose. In conclusion, 4DCT is an appropriate method for assessing the displacement of the GTV centroid in three dimensions. PlanEOE has smaller PTVs and a decreased dose and volume for the normal lung and heart, as compared with Plan3D.
本研究旨在比较基于四维计算机断层扫描（4DCT）的呼吸门控调强放射治疗（IMRT）计划（PlanEOE）与基于三维CT（3DCT）的IMRT计划（Plan3D）在非小细胞肺癌（NSCLC）患者中靶区体积以及靶区和危及器官（OARs）剂量分布的差异。对于17例I-III期NSCLC患者，同时获取了4DCT数据和传统3DCT数据。Plan3D和PlanEOE分别基于3DCT数据和4DCT数据设计。大体肿瘤体积（GTV）质心在左右、前后和上下方向的位移分别为0.13±0.09 cm、0.15±0.1 cm和0.27±0.27 cm。GTVEOE的体积比GTV3D大3.05±5.17 cm³。PTV3D的体积比PTVEOE大72.82±48.65 cm³。PTV3D和PTVEOE在V55.8、V60、V66及均匀性指数方面无显著差异。PTV3D的靶区适形指数低于PTVEOE（P = 0.036）。PlanEOE的肺V10、V20、V30、V40及平均肺剂量（MLD）显著低于Plan3D。对于心脏，PlanEOE的V30和平均剂量显著更低。总之，4DCT是评估GTV质心三维位移的合适方法。与Plan3D相比，PlanEOE的计划靶体积更小，正常肺和心脏的剂量及体积降低。
