Research on SBRT-VMAT plans for non-small cell lung cancer with unilateral ipsilateral double metastatic lesions
10.19745/j.1003-8868.2024193
- VernacularTitle:非小细胞肺癌同层双转移病灶SBRT-VMAT计划设计方式研究
- Author:
Si-Yao ZHONG
1
;
Cheng XU
;
Bin SUN
;
YU-Yan GAO
Author Information
1. 首都医科大学附属北京潞河医院放疗科,北京 101100
- Keywords:
non-small cell lung cancer;
stereotactic body radiation therapy;
volumetric modulated arc therapy;
radiotherapy plan design;
double metastatic lesions;
singlecenter plan;
multicenter plan
- From:
Chinese Medical Equipment Journal
2024;45(10):49-53
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study the effects of different SBRT-VMAT plans for non-small cell lung cancer(NSCLC)with unilateral ipsilateral double metastatic lesions on received dose,monitor unit(MU),conformity index(CI)and gradient index(GI)of the lung,so as to provide references for therapy planning of the patient above.Methods A total of 11 NSCLC patients with unilateral ipsilateral double metastatic lesions were selected,with three plans developed for each patient by the volumetric modulated arc therapy(VMAT).The inner target areas ITV1 and ITV2 were contoured based on the maximum projection image of the 4D-CT localization mode,which were uniformly expanded externally by 3 mm to obtain the plan target area PTV1 and PTV2,and then PTV1 was added with PTV2 to get PTV12.The first planning mode had the centers of PTV1 and PTV2 target areas as the treatment centers,and two separate plans of plan-1 and plan-2 were developed and then combined into a plan-sum plan for dose evaluation;the second planning mode had the centers of PTV1 and PTV2 target areas as the treatment center,resepctively,and a multicenter plan(plan-D)was formed.The third planning mode had the center of PTV12 target area as the treatment center,and a single-center plan(plan-S)was designed.To meet the requirements of prescribed dose,plan-1 and plan-2 of plan-sum were normalized to PTV1 and PTV2 95％volume and plan-S and plan-D were normalized to PTV 12 95％volume.The three planning modes were compared in terms of received dose,MU,CI and GI of the lung.SPSS 25.0 software was carried out for statistical analysis.Results Plan-S had no significant differences with Plan-sum except V5(P＞0.05),whose V10,V20,V30 and mean dose were significantly lower than those of plan-sum(P＜0.05);plan-D had its received dose and mean dose statistically lower than those of plan-sum(P＜0.05);plan-S and plan-D had no obvious differences in received dose of the lung(P＞0.05).Plan-sum had the CI significantly lower than those of plan-S and plan-D(P＜0.05);plan-S and plan-D had no statistically differences in CI(P＞0.05).Plan-D had the GI significantly lower than plan-S and plan-sum(P＜0.05).Plan-S and plan-sum had no significant differences in GI(P＞0.05).Plan-D and plan-sum had no statistical differences in MU(P＞0.05),which had the MUs significantly higher than that of plan-S(P＜0.05).Conclusion A multicenter planning mode may be used for optimizing dose distribution and enhancing conformity in case the patient can tolerate prolonged immobilization in a fixed position,and a singlecenter planning mode should be adopted to shorten treatment time when the patient is in poor physical conditions.[Chinese Medical Equipment Journal,2024,45(10):49-53]
