宫颈癌放射治疗中膀胱充盈差异对剂量的影响研究  

Effect of different bladder filling on dose in cervical cancer radiotherapy

作　　者：葛彬彬[1] 王君辉 吴建亭[1] 刘海涛[1] 翟小刚[1] 储开岳[1] GE Bin-bin;WANG Jun-hui;WU Jian-ting;LIU Hai-tao;ZHAI Xiao-gang;CHU Kai-yue(Department of Radiotherapyf Nantong Tumor Hospital'Tumor Hospital Affiliated to Nantong University,Nantong 226361,Jiangsu,China)

机构地区：[1]南通市肿瘤医院·南通大学附属肿瘤医院,江苏南通226361

出　　处：《生物医学工程与临床》2021年第5期569-574,共6页Biomedical Engineering and Clinical Medicine

基　　金：江苏省重点研发计划项目(BE2017679);南通市指导性计划项目(GJZ17043)。

摘　　要：目的研究膀胱充盈差异对宫颈癌放射治疗中计划靶区(PTV)、危及器官的剂量学影响,并定量分析给出适宜的膀胱充盈容量。方法选择术后接受放射治疗的宫颈癌患者50例,年龄34~69岁,中位年龄56岁。分别获取膀胱充盈与空虚状态下的CT图像,并勾画靶区、危及器官,相同优化参数设计计划,分别记录靶区、危及器官的相关剂量学参数。根据膀胱充盈程度的不同,分为A组(尿急尿量<250 mL或空虚尿量大于尿急尿量1/3)和B组(膀胱尿量> 250 mL或空虚尿量小于尿急尿量1/3),并进行分析,得出最优的临床膀胱充盈量。结果 A组患者膀胱充盈与空虚状态下,靶区和危及器官变化差异无统计学意义(P> 0.05);B组患者在膀胱排空状态下较充盈状态,膀胱体积减小、PTV体积增大,差异具有显著统计学意义[(80.0±29.1) cm^(3)vs (486.3±149.6) cm^(3)、(1 564.0±281.0) cm^(3)vs (1 490.7±269.5) cm^(3);P=0.000、0.000]。B组膀胱充盈较空虚状态膀胱及小肠的V_(30)、V_(35)、V_(40)都有减小,差异均有显著统计学意义(P=0.000);直肠、乙状结肠、股骨头、盆骨等其他危及器官受照剂量变化比较,两组差异均无统计学意义(P> 0.05)。两组计划适形指数、均匀性指数差异无统计学意义(P> 0.05),而膀胱及小肠的V_(30)、V_(35)、V_(40)在膀胱排空状态下增加有显著统计学意义(P=0.000)。B组患者膀胱体积与靶区体积及膀胱、小肠受量之间的相关性分析显示,小肠受量V_(30)、V_(35)、V_(40)与膀胱体积的相关系数绝对值均大于0.7(r=-0.802、-0.791、-0.761,P=0.000)。膀胱体积与膀胱受量之间的相关性,除了V_(40)有低度负相关外(r=-0.406,P <0.05),其他无相关性。结论充盈的膀胱容量建议至少为250 m L,在此范围内较多的尿量能够改变靶区、危及器官的形状、位置,缩小靶区体积,降低膀胱、小肠受量,在危及器官保护上更具优势。Objective To analyze the dosimetry effects of bladder filling on planned target volume(PTV) and organ at risk(OAR)in cervical cancer radiotherapy, and quantitatively analyze appropriate bladder filling. Methods Fifty patients with cervical cancer performed postoperative radiotherapy were enrolled, which aged 34-69 years old with mean age of 56 years old. The CT images of bladder filling and emptiness were obtained. The target area, OAR, and the same optimization parameter design plan were outlined, and relevant dosimetry parameters of PTA and OAR were recorded, respectively. According to bladder filling, all of them were divided into group A(urinary urgency < 250 mL or emptiness urine greater than 1/3 of urine urgency) and group B(urinary bladder > 250 mL or emptiness urine less than 1/3 of urinary urgency), the data was analyzed to obtain appropriate bladder filling. Results There was no significant difference of PTA and OAR between bladder filling and bladder emptiness in group A(P > 0.05). However, in group B, compared with bladder filling, volume of bladder emptiness was reduced and PTV was increased, and difference was statistically significant[(80.0 ± 29.1) cm^(3) vs(486.3 ± 149.6) cm^(3),(1 564.0 ± 281.0) cm^(3) vs(1 490.7 ± 269.5) cm^(3);P = 0.000, 0.000];bladder and small intestine V_(30), V_(35), and V_(40) of bladder filling were all statistically significantly reduced than bladder emptiness(P = 0.000). There was no significant difference in exposure dose of OAR at rectum, sigmoid colon, femoral head and pelvis between 2 groups(P > 0.05). There were no statistically significant differences in planned conformity index and uniformity index(P > 0.05), while the V_(30), V_(35), and V_(40) at bladder and small intestine of bladder emptiness was statistically significantly increased than bladder filling(P = 0.000). The correlation analysis in bladder volume and target volume, bladder and small intestine volume showed that the absolute value of correlation coefficient between small intestine volume V_(30)

关 键 词：宫颈癌 放射治疗 膀胱容量 充盈程度 剂量学 危及器官 器官保护 

分 类 号：R730.55[医药卫生—肿瘤] R737.33[医药卫生—临床医学]