Error Analysis of Different Labeling Methods in Radiotherapy for Cervical Cancer
Objective:To analyze the difference of the positioning accuracy of intensity modulated radiotherapy(IMRT)for cervical cancer using line marking and tattoo marking,so as to provide reference for clinical decision-making.Methods:100 patients with cervical cancer who received accelerator treatment in the radiotherapy department of our hospital from October 2020 to February 2021 were selected as the study subjects.Among them,50 patients used body surface tattoo to mark the placement site(body surface tattoo group),and 50 patients used body surface line drawing to mark the placement site(body surface line drawing group).All patients took 0˚ and 90˚ field verification films before treatment and once a week after treatment,registered the obtained data with the planned CT images,and obtained the positioning errors of the patient's head foot direction(LNG),left and right direction(LAT)and ventral dorsal direction(VRT).The number of times the center point of the patient is offset by different marking methods.Results:The head and foot positioning error in the tattoo group was(1.300±0.870)mm,which was smaller than that in the line drawing group(2.77±1.362)mm(P<0.01);The positioning error in the left and right directions was(1.230±0.983)mm,which was smaller than that in the line drawing group(2.160±1.220)mm(P<0.05);The positioning error of the front and rear directions was(1.250±0.936)mm,which was smaller than that of the line drawing group(2.330±1.371)mm(P<0.01).The percentage of deviations from the center of the positioning distance exceeding 3mm in the body surface line group is 98%.The percentage of deviations from the center of the positioning distance exceeding 3mm in the body tattoo group is 31%,significantly lower than that of the body surface line group.The measurement data of the two groups were tested by rank sum test,and the difference between the two groups was statistically significant(P<0.05).Conclusion:In the body surface tattoo group,the setup errors in the head-foot direction,left-right direction,and front-to-back direction were significantly smaller than those in the body surface line drawing group.In addition,the percentage of the number of times that the distance from the center of the setup was more than 3mm in the body surface tattoo group was significantly smaller than that of the body surface line drawing group.Therefore,in clinical practice,tattoo marking can be considered as a priority for cervical cancer radiotherapy.
万方数据
维普
