【作者】 李斌；

【导师】 刘林林；

【作者基本信息】 吉林大学 ， 临床医学硕士（肿瘤学）（专业学位）， 2021， 硕士

【摘要】 目的:分析局部晚期宫颈癌调强放疗治疗过程中,膀胱体积的变化对于正常组织受照射剂量的影响,为本研究单位在宫颈癌外照射治疗提供参考和帮助。材料与方法:选取2018年12月至2020年12月于吉林大学第二医院放疗科行宫颈癌根治术后预防性外照射调强放疗的局部晚期宫颈癌患者,共计54例,FIGO分期为ⅠB2、ⅠB3和ⅡA2期。行CT模拟定位,定位前嘱患者憋尿至舒适状态并已做好肠道准备。放疗科医师先勾画危及器官,然后在此基础上勾画靶区,由一名物理师在Varian Eclipse13.5治疗计划系统上进行放射治疗计划设计,处方剂量PTV均为DT 50Gy,2.0Gy/次,5次/周。计划完成后根据等剂量曲线评估靶区,根据剂量体积直方图(DVH)评价危及器官限值。在定位CT模拟图像上测量膀胱体积,根据膀胱体积将54例患者分为3组:A组,膀胱体积V≤200ml;B组,200ml<膀胱体积V≤400ml;C组,膀胱体积V>400ml。并在治疗计划系统计算每一位患者膀胱、直肠的D2cc、D1cc和D0.1cc,以及双侧股骨头的D1%。使用SPSS 22.0进行统计学分析,分析不同膀胱体积的剂量学数据。结果:膀胱受照剂量:不同膀胱体积分组下的膀胱D0.1cc、D1cc和D2cc组测得受照剂量值不同,差异存在统计学意义(P<0.05)。两两比较发现,D0.1cc组中,膀胱体积200～400ml的受照剂量小于膀胱体积0～200ml的受照剂量(P=0.014),也小于膀胱体积400ml以上的受照剂量(P=0.027),差异存在统计学意义;D1cc组中,膀胱体积200～400ml的受照剂量小于膀胱体积0～200ml的受照剂量(P=0.04),也小于膀胱体积400ml以上的受照剂量(P=0.02),差异存在着统计学意义;D2cc组中,膀胱体积200～400ml的受照剂量小于膀胱体积0～200ml的受照剂量(P=0.037),也小于膀胱体积400ml以上的受照剂量(P=0.026),差异存在着统计学意义。综上,膀胱体积在200～400ml之间膀胱的D0.1cc、D1cc和D2cc剂量最小,分别为(50.86±2.75)Gy、(50.37±2.77)Gy和(50.20±2.72)Gy。直肠受照剂量:不同膀胱体积分组测得受照剂量值差异没有统计学意义(P>0.05),尚不能认为膀胱体积在0～200ml、200～400ml与400ml以上时直肠受照剂量结果有差异。双侧股骨头受照剂量:不同膀胱体积分组测得受照剂量值差异没有统计学意义(P>0.05),尚不能认为膀胱体积在0～200ml、200～400ml与400ml以上时双侧股骨头的平均受照剂量结果有差异。结论:1.在局部晚期宫颈癌调强放疗中,膀胱充盈状态改变了膀胱的受照剂量。2.膀胱充盈状态对直肠、双侧股骨头受照剂量无明显影响。3.最佳的膀胱憋尿体积在200～400ml之间,可以使膀胱受照剂量达到最小,可能使放疗所致的放射性膀胱炎发生概率降低。更多还原

【Abstract】 Objective:To analyze the influence of the change of bladder volume on the radiation dose to normal tissues during the treatment of local advanced cervical cancer with intensity-modulated radiotherapy,and provide reference and help for the research unit in the treatment of cervical cancer with external radiation.Materials and methods:A total of 54 patients with locally advanced cervical cancer who underwent prevention of external beam intensity-modulated radiotherapy after radical resection of cervical cancer in our department from December 2018 to December 2020 were selected.The FIGO staging is IB2,IB3 and IIA2.Perform CT simulation positioning,and instruct the patient to hold back the urine to a comfortable state and prepare the bowel before positioning.The target area and organs at risk were delineated,and a physicist carried out a plan design on the Varian Eclipse13.5 treatment planning system.The prescribed dose PTV was DT 50 Gy,2.0Gy/time,5 times/week.After the plan is completed,the target area and organ-at-risk limits will be evaluated according to the DVH chart and isodose curve.The bladder volume was measured on the location CT simulation image.According to the bladder volume,54 patients were divided into 3 groups,group A: bladder volume V≤200ml;group B: 200 ml < bladder volume V ≤ 400ml;group C:bladder volume V>400ml.And calculate the D2 cc,D1cc and D0.1cc of each patient’s bladder and rectum,and D1% of bilateral femoral heads in the treatment planning system.Use SPSS 22.0software to analyze the dosimetry data among the three groups.Result:Bladder exposure dose: There were significant differences in the dose values of bladder in different bladder volume groups(P<0.05).The results showed that the dose of 200～400ml bladder volume was less than that of 0～200ml bladder volume(P=0.014)and more than 400 ml bladder volume(P=0.027)in D0.1cc group;In D1 cc group,the dose of 200～400ml bladder volume was less than that of 0～200ml bladder volume(P = 0.04),and it was also less than that of 400 ml bladder volume(P = 0.02);In D2 cc group,the dose of200～400ml bladder volume was less than that of 0～200ml bladder volume(P = 0.037),and it was also less than that of more than400 ml bladder volume(P = 0.026).In conclusion,the dose of D0.1cc,D 1cc and D 2cc was the lowest in the bladder volume between 200 ml and 400 ml,which were(50.86±2.75)Gy、(50.37±77)Gy and(50.20±2.72)Gy。Rectal exposure dose: The rank sum test was performed on each group.There was no statistically significant difference in exposure dose values measured by different bladder volume groups(P>0.05).It is not yet believed that the results of rectal exposure doses are different when the bladder volume is 0～200ml,200～400ml and 400 ml or more.Exposure dose of bilateral femoral heads: analysis of variance was performed for each group;there was no statistically significant difference in exposure dose values measured by different bladder volume groups(P>0.05),It is not yet believed that the average exposure dose of bilateral femoral heads is different when the bladder volume is 0～200ml,200～400ml and 400 ml or more.Conclusions:1.In intensity-modulated radiotherapy for locally advanced cervical cancer,the filling state of the bladder changes the radiation dose of the bladder.2.The filling state of the bladder has no significant effect on the radiation dose of the rectum and bilateral femoral heads.3.The best bladder holding urine volume is between 200～400ml,which can minimize the radiation dose of the bladder,which may reduce the probability of radiation cystitis caused by radiotherapy.更多还原