CAJ | 학술논문

目的用兆伏(MV)X线平片测定乳腺托架固定下全乳放疗摆位误差,探讨自由呼吸状态下临床靶体积(CTV)外扩至计划靶体积(PTV)的边界.方法选取2010-2012年本科行保乳术后调强放疗的29例乳腺癌患者,其中17例行全乳照射,12例行全乳和锁骨上淋巴引流区照射.均采用乳腺托架体位固定,利用放疗计划系统数字重建图像与治疗期间拍摄正交MV验证平片比较,确定摆位误差.对接受锁骨上淋巴引流区照射与未照射的误差比较行成组t检验.结果全体患者共获得正交MV验证平片图像127套,平均每人(4.4±1.2)套.全组患者左右、上下、前后方向摆位误差分别为(0.9±3.1)、(0.7±3.0)、(1.2±2.1)mm,摆位误差的系统误差分别为3.1、3.0、2.1 mm,随机误差分别为2.7、3.3、3.5 mm；做与未做锁骨上淋巴引流区照射者的摆位误差无差异(t=0.02、0.20、0.20,P=0.98、0.85、0.85).CTV至PTV边界左右、上下、前后方向分别为9.6、9.8、7.7 mm.结论用乳腺托架固定全乳调强放疗的CTV外放PTV在左右、上下、前后方向上应至少分别为9.6、9.8、7.7 mm.
목적 용조복(MV)X선평편측정유선탁가고정하전유방료파위오차,탐토자유호흡상태하림상파체적(CTV)외확지계화파체적(PTV)적변계.방법 선취2010-2012년본과행보유술후조강방료적29례유선암환자,기중17례행전유조사,12례행전유화쇄골상림파인류구조사.균채용유선탁가체위고정,이용방료계화계통수자중건도상여치료기간박섭정교MV험증평편비교,학정파위오차.대접수쇄골상림파인류구조사여미조사적오차비교행성조t검험.결과 전체환자공획득정교MV험증평편도상127투,평균매인(4.4±1.2)투.전조환자좌우、상하、전후방향파위오차분별위(0.9±3.1)、(0.7±3.0)、(1.2±2.1)mm,파위오차적계통오차분별위3.1、3.0、2.1 mm,수궤오차분별위2.7、3.3、3.5 mm；주여미주쇄골상림파인류구조사자적파위오차무차이(t=0.02、0.20、0.20,P=0.98、0.85、0.85).CTV지PTV변계좌우、상하、전후방향분별위9.6、9.8、7.7 mm.결론 용유선탁가고정전유조강방료적CTV외방PTV재좌우、상하、전후방향상응지소분별위9.6、9.8、7.7 mm.
Objective To quantify the setup errors measured with orthogonal megavoltage X-ray film in breast cancer patients immobilized in breast bracket.To probe into the margins from clinical target volume (CTV) to planning target volume (PTV) in 3 directions.Methods Repeat orthogonal megavoltage X-ray films were acquired for routine of fine setup verification in 29 breast cancer patients after conserving surgery,17 received whole breast radiation and 12 received both whole breast and supraclavicular node radiation.All patients were immobilized in the supine position with both arms raised over their heads,using a personalized α-cradle (breast bracket).Registrations of the bony anatomy for megavoltage X-ray films to digitally reconstructed-radiographs from the planning CT were compared.Systematic and random setup errors were quantified,and the differences between groups with and without supraclavicular node radiation were compared by independent two-sample t-test.Results The mean set up deviation,systematic error and random error were (0.9±3.1) mm,(0.7±3.0) mm,(1.2±2.1) mmand3.1 mm,3.0 mm,2.1 mm and 2.7 mm,3.3 mm,3.5 mm in the mediolateral,superoinferior and anteroposterior dimensions.There is no difference of set up deviation between patients received supraclavicular node radiation and those did not (t =0.02,0.20,0.20,P =0.98,0.85,0.85).The margins from CTV to PTV were 9.6 mm,9.8 mm,7.7 mm in mediolateral,superoinferior and anteroposterior directions.Conclusion For whole breast irradiation patients immobilized with breast bracket,the margins from CTV to PTV were recommended as 9.6 mm,9.8mm,7.7 mm in mediolateral,superoinferior and anteroposterior directions.