摘要
目的探讨摆位误差对宫颈癌放疗靶区和危及器官剂量分布的影响。方法选择2018年8月到2020年6月在该院诊治的宫颈癌患者84例作为研究对象,所有患者都给予调强适形放射治疗(IMRT),在放疗期间记录摆位误差,并采用锥形束CT(CBCT)进行误差校正,记录放疗靶区和危及器官剂量的分布情况。结果摆位误差纠正后在X、Y、Z轴方向的摆位误差分别为(0.21±0.02)mm、(0.77±0.03)mm、(0.35±0.03)mm,与摆位误差纠正前[(2.27±0.21)mm、(4.18±0.28)mm、(2.59±0.11)mm]比较,差异均有统计学意义(P<0.05)。摆位误差纠正后V100、直肠V40、膀胱V40均低于摆位误差纠正前(P<0.05),小肠V40、结肠V40纠正前后比较差异无统计学意义(P>0.05)。摆位误差纠正后PTV1、PTV2、PTV3照射剂量均低于摆位误差纠正前(P<0.05)。结论宫颈癌患者放疗时在X、Y、Z轴方向均存在一定的摆位误差,纠正摆位误差有助于降低危及器官剂量分布与减少PTV照射剂量。
Objective To investigate the influence of set-up errors on the dose distribution of target areas and organs at risk in cervical cancer radiotherapy.Methods From August 2018 to June 2020,84 patients with cervical cancer diagnosed and treated in the hospital were enrolled in the study.All patients were treated with intensity-modulated radiotherapy(IMRT),and the set-up errors were recorded in radiotherapy.Cone-beam CT(CBCT)were used to perform error correction and the dose distribution of radiotherapy target areas and organs at risk were recorded.Results After the setting error were corrected,the setting errors on the X,Y,and Z axes were(0.21±0.02)mm,(0.77±0.03)mm,(0.35±0.03)mm,respectively,which compared with those before the setting error correction[(2.27±0.21)mm,(4.18±0.28)mm,(2.59±0.11)mm],the differences were statistically significant(P<0.05).The V100,rectal V40,and bladder V40 values after the correction of the set-up error were lower than those before the correction of the setting error(P<0.05).There were no significant difference between the V40 of the small intestine and the colon before and after the correction(P>0.05).The radiation doses of PTV1,PTV2 and PTV3 after the correction of the set-up error were all lower than before the correction of the setting error(P<0.05).Conclusion There are certain set-up errors in the X,Y,and Z-axis directions for patients with cervical cancer in radiotherapy.Correcting the set-up errors can reduce the dose distribution of organs at risk and reduce the PTV radiation dose.
作者
牛利君
NIU Lijun(Department of Oncology Radiotherapy,Ankang People′s Hospital,Ankang,Shaanxi 725000,China)
出处
《检验医学与临床》
CAS
2021年第11期1571-1573,1578,共4页
Laboratory Medicine and Clinic
关键词
摆位误差
宫颈癌
锥形束CT
放疗靶区
危及器官
调强放射治疗
set-up error
cervical cancer
cone-beam CT
radiotherapy target area
organ at risk
intensity-modulated radiotherapy
