摘要
目的 研究宫颈癌包含腹主动脉旁淋巴引流区的容积旋转调强(VMAT)计划设计中射野等中心位置对靶区和危及器官剂量分布的影响。方法 随机选择于2018年至2021年在天津市中心妇产科医院行放射治疗的宫颈癌根治17例和术后7例患者的CT图像进行研究。患者年龄34~71岁,平均年龄51.8岁;国际妇产科联盟(FIGO)分期为Ⅱb到Ⅲb期,病理诊断为中低分化鳞癌。所有患者均需进行腹主动脉旁延伸野照射。对每例患者,按头足方向位置分别选择射野等中心位置为近靶区头侧(Y1M)、近靶区中部(MID)、近靶区足侧(Y2M),进行分组计划设计,比较剂量学参数。结果 MID组和Y2M组在计划靶区(PTV)的95%剂量覆盖率D_(95%)上差异无统计学意义[MID:(46.69±1.83) Gy;Y2M:(46.74±1.81) Gy],两者均高于Y1M组[(46.52±1.80) Gy]且差异有统计学意义(P<0.05)。危及器官方面,Y2M组双侧肾脏、肝脏的平均剂量D_(mean)和剂量体积参数V_(6 Gy)、V_(15 Gy)等多项参数上显著高于其他两组;在小肠平均剂量显著低于其他两组[Y2M (25.33±5.94) Gy vs Y1M(25.52±5.99) Gy、MID(25.44±5.88) Gy]。MID组与Y1M组相比,后者右侧肾脏的V_(15 Gy)更高[MID (16.25±9.00) Gy vs Y1M(16.90±9.81) Gy],其他参数差异无统计学意义(P>0.05)。结论 将等中心选为靶区头足方向中间位置可较好兼顾靶区和危及器官的剂量分布。
Objective To study effects of isocenter location on target volume and organs at risk(OAR) dose distribution of cervical cancer with para-aortic lymphatic drainage in volumetric modulated arc therapy(VMAT).Method From 2018 to 2021,CTimages of 17 patients with radical cervical cancer performed radiotherapy and 7 patients after surgery were randomly enrolled,which aged 34-71 years old with mean age of 51.8 years old.The International Federation of Gynecology and Obstetrics(FIGO) stage wasⅡb toⅢb,and pathological diagnosis was moderately and poorly differentiated squamous cell carcinoma.All of them performed para-aortic extended field irradiation.According to isocenter position of the field in cephalic side near target area (Y1M),middle near target area (MID),and foot side near target area (Y2M),different groups were designed,and dosimetric parameters were compared in 3 groups.Results There was no significant difference between MID group and Y2M group in 95%dose coverage of planning target volume(PTV)(D_PTV)[MID:(46.69±1.83) Gy;Y2M:(46.74±1.81) Gy],both two groups were statistically significant higher than those of Y1M group[(46.52±1.80) Gy(P<0.05)].In OAR,group Y2M were significantly higher in parameters of bilateral kidneys and liver such as mean dose(D) and dose volume parameters Vand V,and significantly lower in Dof intestine than the other two groups[Y2M (25.33±5.94) Gy vs Y1M(25.52±5.99) Gy,MID(25.44±5.88) Gy].The Vof right kidney in Y1M group was higher than that in MIDgroup[MID(16.25±9.00) Gy vs Y1M(16.90±9.81) Gy],and there was no significant difference in other parameters(P>0.05).Conclusion It is demonstrated that isocenter as the middle position of target area in cephalo-foot direction could better balance target area and ORA dose distribution.
作者
郝金龙
曾静
曲芃芃
HAO Jin-long;ZENG Jing;QU Peng-peng(Department of Gynecology and Oncology,Tianjin Central Hospital of Gynecology Obsterics,Tianjin 300199,China)
出处
《生物医学工程与临床》
CAS
2022年第4期450-454,共5页
Biomedical Engineering and Clinical Medicine
基金
天津市卫生健康委员会科研基金资助项目(KJ20109)。
关键词
容积旋转调强放射治疗
宫颈癌
腹主动脉旁延伸野
等中心位置
剂量学参数
volumetric modulated arc therapy(VMAT)
cervical cancer
para-aortic extended-field
field isocenter location
dosimetric parameters