Abstract
Objective:To compare the effects of different automatic normal tissue objective(NTO)weights(WNTO)of Eclipse planning system on intensity modulated radiation therapy(IMRT)of fixed field for abdominal tumor.Methods:Twenty patients with rectal cancer and twenty patients with cervical cancer who received radiotherapy in The Second People's Hospital of Huludao from September 2022 to January 2024 were selected.5 groups of different plans[WNTO20,40,60,80 and 100]were respectively formulated for each patient.Among of them,the WNTO20 plan was control group,and other 4 groups were respectively WNTO40 group,WNTO60 group,WNTO80 group and WNTO100 group.Then,the differences in dosimetry and monitor units(MU)among 5 groups of plans were compared.Results:In the WNTO 80 and 100 groups of patients with rectal cancer,the conformation index(CI)values of target regions of them were respectively 1.02±0.04 and 1.00±0.03,all of which approached to 1,and the CI values of two groups were lower than that of control group,and the differences were statistically significant(t=15.986,18.422,P<0.05).The homogeneity index(HI)of WNTO 80 and 100 groups were respectively 0.09±0.12 and 0.10±0.14,which were higher than that of control group,and the differences were statistically significant(t=-1.371,-1.463,P<0.05).The 52Gy dose volume(Vmax52)of small intestine of the two groups were respectively(4.48±14.49)and(4.77±10.47)cm3,which were higher than that of control group,and the differences were statistically significant(t=-1.360,-2.005,P<0.05).The 30 Gy dose volume percentage(V30 Gy)values of the right femoral heads of the two groups were respectively(12.28±4.57)%and(10.96±4.17)%,which were lower than that of control group,and the differences were statistically significant(t=6.893,6.75,P<0.05).The 30 Gy dose volume percentage(V30 Gy)values of the left femoral head of the two groups were respectively(11.57±4.41)%and(10.17±3.78)%,which were lower than that of control group,and the differences were statistically significant(t=6.782,5.963,P<0.05).The MU value of WNTO100 group was(1254±93)MU,which was higher than that of control group,and the difference was statistically significant(t=-3.741,P<0.05).In the WNTO 80 and 100 groups of patients with cervical cancer,the CI values of target regions of them were respectively 1.03±0.32 and 1.02±0.03,all of which approached to 1,and the CI values of the two groups were lower than those of control group,and the differences were statistically significant(t=20.069,19.475,P<0.05).The HI values of them were respectively 0.07±0.05 and 0.08±0.01,which were higher than that of control group,and the differences were statistically significant(t=-12.445,-19.478,P<0.05).The V30 Gy values of the right femoral heads of the two groups were respectively(16.11±4.71)%and(14.90±4.56)%,which were lower than that of control group,and the differences were statistically significant(t=7.875,8.020,P<0.05).The V30 Gy values of the left femoral head of the two groups were respectively(15.21±3.71)%and(13.93±3.77)%,which were lower than that of control group,and the differences were statistical significance(t=7.617,7.436,P<0.05).The Vmax52 of small intestine of the two groups were respectively(0.82±1.10)and(4.47±8.81)cm3,which were higher than that of control group,and the difference was statistically significant(t=-2.985,-2.388,P<0.05).Conclusion:The WNTO80 is recommended for IMRT plan of radiotherapy on abdominal tumor,which can more quickly and better meet the assessment conditions of IMRT plan.关键词
直肠癌/宫颈癌/固定野调强/Eclipse计划系统/自动正常组织优化结构(NTO)Key words
Rectal cancer/Cervical cancer/Fix-field intensity/Eclipse planning system/Automatic normal tissue objective(NTO)分类
医药卫生
