胸中段食管癌根治性放疗三维适形放疗与调强放疗剂量学比较

目的：比较食管癌根治性放疗三维适形放射治疗（3D-CRT）与调强放射治疗（IMRT）的剂量分布，探讨IMRT在胸中段食管癌放疗的价值。方法：对10例胸中段食管癌病例分别行3D-CRT和IMRT计划设计，应用剂量体积直方图（DVH）比较两种计划靶区剂量、适形度指数（CI）、不均匀度指数（HI）及正常器官受量。结果：在食管癌根治放疗中，IMRT在靶区剂量分布上与3D-CRT各有优劣；IMRT在正常器官的保护上优势明显；肺V5、V10、V20以及全肺平均剂量IMRT均明显优于3D-CRT；心脏V30IMRT低于3D-CRT；脊髓剂量没差别。结论：食管癌根治放疗中IMRT计划在靶区剂量分布上没有明显优势。但可更好保护正常组织。

Dosimetric Analysis of Preoperative Three Dimensional Conformal and Preoperative Intensity Modulated Radiotherapy for Middle Esophageal Cancer

Objective:To compare the dose distributions of three-dimensional conformal radiotherapy planning(3D-CRT) and intensity modulated radiotherapy(IMRT) and explore the value of IMRT in the middle of esophageal cancer.Methods:The 3D-CRT and IMRT plans were designed in 10 cases of middle esophageal cancer patients,respectively.The application of dose-volume histogram(DVH) to compare the target volume dose,conformal index(CI),homogeneity index(HI) and the dose of normal structures.Results:With radical radiotherapy in esophageal cancer,the target dose distribution in IMRT and 3DCRT plans had advantages and disadvantages.IMRT had obvious advantages in reducing the normal structures dose.IMRT had better V5,V10,V20 and mean dose of lung compare to 3D-CRT.IMRT plans exposed lower heart to V30 compare to 3D-CRT.The dose of spinal cord did not significant differences in two plans.Conclusions:IMRT plans have no obvious advantage in the target dose distribution of radical radiotherapy in esophageal cancer,but the normal structures will be better protected.