摘要
目的: 分析早期原发胃淋巴瘤不同三维适形放疗技术(3DCRT)的剂量分布特征,为临床优化应用提供参考。方法:选取9例早期原发胃淋巴瘤患者,在空腹状态下做模拟定位CT,并在CT图像上勾画出胃肿瘤和受累淋巴结、临床靶区(CTV)、计划靶区(PTV),以及邻近危及器官(OARs)。每例设计2种放疗计划:四野3DCRT及上下半束六野的优化3DCRT,用剂量体积关系图分析剂量学结果。结果:四野及优化3DCRT的适形指数分别为0.67±0.06及0.64±0.05;剂量不均匀性指数分别为1.10±0.02及1.11±0.03。左、右肾V15在四野3DCRT及优化3DCRT中分别为(47±30)%、(33±18)%和(24±18)%、(12±12)%。优化3DCRT的肝脏V_(20)较四野3DCRT减少24%。结论:3DCRT能够给予肿瘤靶区均匀的剂量分布,而采用优化六野3DCRT可以更好的保护肾脏、肝脏等危及器官。
Objective： To evaluate the dosimetric characters of different three-dimensional conformal radiation therapy （ 3DCRT ） techniques for early stage primary gastric lymphoma treatment and provide a reference for its optimized clinical application. Methods： Nine patients with early stage primary gastric lymphoma were enrolled for the current research. A simulated CT position was made in the fasting state. Gastric tumors with invaded lymph nodes, clinical target volume, and planning target volume （ PTV ） were contoured on each computed tomography scan. Organs at risk （ OARs ）, such as each kidney, the liver, and the spinal cord were also contoured. Treatment planning for the ordinary four-field 3DCRT and optimized six-field 3DCRT was conducted for each patient. The prescribed PTV dose was 36 Gy. The dose distribution of PTVs and OARs were compared using the dose-volume relationship line graph. Results： The conformal indices for the ordinary four-field 3DCRT and optimized six-field 3DCRT were 0.67 ±0.06 and 0.64 ± 0.05, respectively, whereas the inhomogeneity indices were 1.10 ±0.02 and 1.11 ±0.03, respectively. The V15 （ ratio of the kidney volume accepted higher than 15 Gy irradiation ） values for the left and right kidneys in the ordinary four-field 3DCRT and optimized six-field 3DCRT were 47% ±30%, 33%± 18%, and 24% ±18%, and 12% ±12%, respectively. The V20 （ ratio of the liver volume accepted higher than 20 Gy irradiation ） values for the liver in the optimized six-field 3DCRT decreased by 24% compared with those of the ordinary four-field 3DCRT. Conclusion： 3DCRT can successfully achieve the ideal dose distribution and coverage over the target volume, and the optimized six-field 3DCRT can better protect the kidneys, liver, and other OARs.
出处
《中国肿瘤临床》
CAS
CSCD
北大核心
2011年第14期855-858,共4页
Chinese Journal of Clinical Oncology
关键词
胃原发淋巴瘤
放射疗法
三维适形放疗
剂量体积关系图
Primary gastric lymphoma
Radiotherapy
Three-dimensional conformal radiation therapy
Dose-volume relationship line graph
