CAJ | 학술논문

目的比较三维适形(3 D-CRT)、逆向调强(IMRT)及旋转调强(V-MAT)3种部分乳腺外照射(EB-PBI)治疗计划的剂量学差异.方法选择定位影像资料完整的12例保乳术后行EB-PBI患者,每例患者分别设计3D-CRT、IMRT、V-MAT 3种治疗计划,比较3种计划的靶区剂量分布、危及器官受照剂量及所需机器跳数(MU)和治疗时间.结果 3D-CRT计划的靶区适形度最差,V-MAT计划的处方剂量靶区覆盖率及靶区剂量均匀性最差.3D-CRT计划中患侧肺V5、V10和平均剂量低,而患侧肺V30高；计划间患侧肺V20差异无统计学意义；V-MAT计划中15、20和25 Gy剂量包绕的同侧正常乳腺体积少；对于心脏V5、平均剂量及最大剂量、对侧肺平均剂量、甲状腺平均和最大剂量,IMRT＞ V-MAT＞ 3D-CRT,计划间两两比较差异均有统计学意义(z=-2.94 ～ -2.09,P＜0.05).3D-CRT、IMRT和V-MAT计划所需MU值分别为417.6 ±34.4、772.8±54.4和631.0±109.0,计划间两两比较差异均有统计学意义(z=-2.93、-2.76、-2.93,P＜0.05)；V-MAT计划施照时间短.结论对于部分乳腺癌的放射治疗,旋转调强计划在降低患侧靶区外正常乳腺组织受照射剂量和减少治疗时间方面优势比较明显.
목적 비교삼유괄형(3 D-CRT)、역향조강(IMRT)급선전조강(V-MAT)3충부분유선외조사(EB-PBI)치료계화적제량학차이.방법 선택정위영상자료완정적12례보유술후행EB-PBI환자,매례환자분별설계3D-CRT、IMRT、V-MAT 3충치료계화,비교3충계화적파구제량분포、위급기관수조제량급소수궤기도수(MU)화치료시간.결과 3D-CRT계화적파구괄형도최차,V-MAT계화적처방제량파구복개솔급파구제량균균성최차.3D-CRT계화중환측폐V5、V10화평균제량저,이환측폐V30고；계화간환측폐V20차이무통계학의의；V-MAT계화중15、20화25 Gy제량포요적동측정상유선체적소；대우심장V5、평균제량급최대제량、대측폐평균제량、갑상선평균화최대제량,IMRT＞ V-MAT＞ 3D-CRT,계화간량량비교차이균유통계학의의(z=-2.94 ～ -2.09,P＜0.05).3D-CRT、IMRT화V-MAT계화소수MU치분별위417.6 ±34.4、772.8±54.4화631.0±109.0,계화간량량비교차이균유통계학의의(z=-2.93、-2.76、-2.93,P＜0.05)；V-MAT계화시조시간단.결론 대우부분유선암적방사치료,선전조강계화재강저환측파구외정상유선조직수조사제량화감소치료시간방면우세비교명현.
Objective To compare the dosimetric differences of three-dimensional conformal radiotherapy (3D-CRT), intensity-modulated radiotherapy (IMRT) and volumetric modulated arc radiotherapy(V-MAT) for external beam partial breast irradiation.Methods Twelve patients with breast cancer receiving breast-conserving surgery and external beam partial breast irradiation were enrolled.Three different techniques including 3D-CRT,IMRT and V-MAT were designed for each patient.The dosimetry in the target,the dose to the organs at risk(OAR),the MU and delivery time were compared.Results All three plans met the clinical requirement. 3D-CRT showed the worst conformity in target. V-MAT provided the lowest target coverage and homogeneity in target.3D-CRT plans showed the lowest values for the V5,V10,mean dose and the highest values for V30 in the ipsilateral lung.No statistically significant differences were observed in V20 of the ipsilateral lung among three plans.V-MAT showed the lowest values in ipsilateral normal breast volume 15,20 and 25 Gy post-irradiation.For V5,the mean and max dose in heart,the mean dose in contralateral lung and the mean,max dose in thyroid,IMRT and 3D-CRT showed the highest and lowest value respectively(z =-2.94 - -2.09,P ＜ 0.05 ).The MUs in 3D-CRT,IMRT and V-MAT were 417.6 ± 34.4,772.8 ± 54.4 and 631.0 ± 109.0,respectively (z =- 2.93, - 2.76,-2.93,P ＜ 0.05 ). V-MAT significantly reduced the delivery time. Conclusions V-MAT shows significant advantages in reducing the dose in the ipsilateral normal breast and the delivery time compared with 3D-CRT and IMRT.