中间剂量计算模式对食管癌容积旋转调强放射治疗计划的影响

Effect of Intermediate Dose Calculation Module on Volumetric Modulated Arc Therapy Planning for Esophageal Cancer

目的探讨中间剂量计算(IDC)模式对食管癌容积旋转调强放射治疗(VMAT)计划的影响。方法选取2021年12月至2022年8月医院收治的18例食管癌患者,在Eclipse15.6治疗计划系统上重新设计VMAT计划,分为未应用IDC模式计划和应用IDC模式计划,比较两种计划的靶区和危及器官(OARs)的剂量学差异。结果两种计划靶区的D_(98)、D_(2)、D_(mean)、适形度指数(CI)和均匀性指数(HI)等参数比较,差异有统计学意义(P<0.05)。两种计划双肺的V_(5)、V_(10)、V_(20)、V_(30)和D_(mean)及脊髓D_(max)比较,差异无统计学意义(P>0.05),但应用IDC模式计划的心脏V_(30)、V_(40)、D_(mean)均低于未应用IDC模式计划,差异有统计学意义(P<0.05)。结论应用IDC模式计划较未应用IDC模式计划具有更好的靶区适形度和均匀性,同时降低了OARs剂量,因此,应用IDC模式计划可以提高食管癌VMAT计划的质量。

Objective To investigate the effect of the use of intermediate dose calculation(IDC)module on volumetric modulated arc therapy(VMAT)planning for esophageal cancer.Methods Eighteen patients with esophageal cancer who received radiotherapy in hospital from December 2021 to August 2022 were selected retrospectively,and two group plans were designed for each patient in the Eclipse 15.6 treatment planning system:without and with IDC module,respectively.The dosimetric difference in planning target volume(PTV)and organs at risk(OARs)between two groups were compared.Results There were significant differences in D_(98),D_(2),D_(mean),CI and GI of targets among plans optimized with without IDC module and with IDC module(P<0.05).Compared with without IDC module,there were no significant differences in V_(5)、V_(10)、V_(20)、V_(30) and D_(mean) of lung,and Dmax of spinal cord(P>0.05).Plans with IDC module achieved less V_(30),V_(40) and D_(mean) of heart,the difference was statistically significant(P<0.05).Conclusions Compared with the plans without IDC module,the plans with IDC module demonstrates superior target conformity and homogeneity,and reduces the dose of OARs.Therefore,the use of IDC module in VMAT plans of esophagus cancer patients improves the plans quality.