锥形束CT在宫颈癌放疗中的应用研究  

Application of cone-beam computed tomography for evaluating setup errors in imaging-guided radiation therapy of cervix cancer

作　　者：王多明[1] 秦永辉[1] 古丽娜.库尔班 王若峥[1] 

机构地区：[1]新疆医科大学附属肿瘤医院放疗科,乌鲁木齐830011

出　　处：《新疆医科大学学报》2013年第1期11-15,20,共6页Journal of Xinjiang Medical University

基　　金：新疆维吾尔自治区科技支疆项目(200991137);科技部国际合作项目(2012DFA31560)

摘　　要：目的探讨锥形束CT(cone beam computerized tomography,CBCT)在宫颈癌放疗中的摆位误差及摆位误差对近期疗效、急性放射反应的影响。方法选取初诊宫颈癌患者86例,随机分为图像引导调强放疗组(image guided radiation therapy,IGRT)和调强放疗组(intensity modulated radiotherapy,IMRT),分别为44例和42例。IGRT组应用瓦里安IGRT系统调强放射治疗,分别对每位患者每周1次采集首次摆位后、摆位误差纠正后CBCT图像,获得X(左右方向)、Y(腹背方向)、Z(头脚方向)轴三维方向的移床数值,用于分析其摆位误差;治疗期间观察IGRT组和IMRT组患者的急性放疗毒性反应,治疗结束后评价2组近期疗效。结果 (1)宫颈癌患者共扫描了440次锥形束CT,系统+随机误差在X、Y、Z轴方向分别为(2.68±1.724)、(2.98±1.568)、(2.32±1.702)mm,对这些摆位误差均进行实时纠正,应用CBCT校正后X、Y、Z轴3个方向摆位误差的系统误差和随机误差均低于校正前水平。(2)IGRT与IMRT组比较,0级+Ⅰ级的急性皮肤黏膜反应、肠道反应和泌尿系反应率分别为88.64%与83.33%,90.90%与78.57%,90.90%与83.33%。其中0级+Ⅰ级肠道反应率2组之间差异有统计学意义(P<0.05);2组患者的近期疗效总有效率分别为100%、97.62%,其差异无统计学意义(P>0.05)。结论采用CBCT技术对宫颈癌调强放疗前进行校正,可以缩小放疗过程中的摆位误差,提高放疗过程的精度;有利于降低急性放射反应,进而可能改善宫颈癌放疗的近期疗效。Objective To discuss the setup errors with cone-beam computed tomography （CBCT） in ima ging-guided radiation therapy （IGRT） and the influence of the setup errors on the efficacy and s,de effects of cervix cancer （CC） patients. Methods Eighty six primary CC patients were randomly divided into IG RT group （44 cases） and IMRT group （42 cases）. IGRT group were performed by CBCT once a week to record precorrection and pretreatment positions. We recorded the setup errors at X （left-right）, Y （yen tral-dorsal） and Z （cranial-caudal） directions for Statistical analysis, the acute radiation toxicity reaction during treatment and the recent efficiency were evaluated and compared between two groups. Results （1） A total of 440 CBCT scans were obtained in IGRT group, the systematic errors and random errors in X, Y and Z directions were （2.68±1. 724）, （2.98±1. 568）, （2.32±1. 702） mm, respectively. After correction of the treatment position employing CBCT, the system error and random error were lower than those of former level. （2） The incidence of acute radiation toxicity reaction of skin, digestive and urinary system symptoms （0＋I level） in IGRT group and IMRT group were 88. 64% vs83.33%, 90.90% vs78.57%, 90.90%/ vs 83.33%, respectively, there was statistically significant difference in digestive symptoms （0＋level） between the two groups （P 〈0.05）. The total recent efficiency rate of CC patients were 100% vs 97.62% and no obvious differences were observed between the two groups （P）0.05）. Conclusion Using CBCT technology for correction of the treatment position before IMRT can reduce the setup error and improve the precision of radiation and maybe favorable to reduce the acute radiation reaction and improve recent efficiency in CC patients.

关 键 词：宫颈癌 图像引导放射治疗 摆位误差 近期疗效 急性毒性反应 

分 类 号：R730.5[医药卫生—肿瘤] R737.33[医药卫生—临床医学]