【摘要】 目的:对比研究胃癌术后患者辅助割裂野单中心半野适形放疗(3D-SF-CRT)、三维适形放疗(3D-CRT)及前后对穿野常规放疗(AP-PA)的剂量学特点。方法:在放疗计划系统为有术后辅助放疗适应证的胃癌患者15例设计相同计划靶体积(PTV)下的3种放射治疗方案,处方剂量均为45 Gy,根据剂量体积直方图(DVH)计算并比较3种放疗方法各参数的标准差。结果:3种放疗技术的计划靶区的V95、D95差异无统计学意义(P值分别为0.521和0.241),2种适形放疗技术的适形指数差异无统计学意义(P=0.189),但均高于AP-PA,P=0.02。3D-SFCRT、3D-CRT和AP-PA的脊髓最大点剂量分别为(33.24±0.45)、(35.01±0.48)和(51.90±0.92)Gy,P=0.06。3D-SFCRT的双肾V20~V45均小于其他2种放疗技术,P<0.05。3D-SFCRT的肝脏V25~V45比3D-CRT高,但差异均无统计学意义,P=0.261。3D-SFCRT的右肾T5/5明显低于3D-CRT,P值分别为0.001和0.008;在左肾、脊髓及肝脏,差异无统计学意义,P值均<0.05;与AP-PA相比,3D-SF-CRT的脊髓、双肾的T5/5明显为低,P值均<0.05;在肝脏两者类似,P=0.261。结论:胃癌术后辅助放疗,与常规适形放疗技术相比,应用割裂野单中心半野适形照射技术能在确保PTV获得满意剂量分布的同时,更好地保护脊髓及双侧肾脏,值得推广。更多还原

【Abstract】 OBJECTIVE:To compare the features of dosiology among 3D split-field conformal radiaotherapy(3D-SFCRT),3D conformal radiaotherapy(3D-CRT) and parallelopposed anteroposterior-posteroanterior field radiaotherapy(AP-PA).METHODS: A total of 15 cases of postoperative gastric cancer patients who had indications of adjuvant radiaotherapy were involved.DVHs of 3D-SFCRT,3D-CRT and AP-PA of evrey case were separately acquired from treatment planning system(TPS).Each prescribed dose of any radiaotherapy technique was 45 Gy.Then the standard deviations of some parameters were compared among the three techniques.RESULTS: V95 and D95 about PTV had no difference among the three techniques(P=0.521;P=0.241).There was no difference of CIs between the two conformal techniques(P=0.189),but the conformal techniques had better PTV fitness than the AP-PA one(P=0.02).The maximum dose points of spinal cord in 3D-SFCRT,3D-CRT,and AP-PA were(33.24±0.45),(35.01±0.48) and(51.90±0.92) Gy,respectively,and there was a difference between any two techniques(P=0.06).V20-V45 of kidneys in 3D-SFCRT was less than that in the other two(P<0.05).V25-V45 of liver was similar among the three techniques(P=0.261).T5/5 of right kidney was obviously lower in 3D-SFCRT than that in 3D-CRT(P=0.001;P=0.008),but T5/5 of spinal cord,left kidney or liver was all no difference between the two conformal methods(P<0.05).Compared with AP-PA,T5/5 of 3D-SFCRT in spinal cord and kidneys,were lower(P<0.05),and similar in liver(P=0.261).CONCLUSION: There are similar dose distribution of PTV,less dose of spinal cord and kidneys in 3D-SFCRT than that in 3D-CRT in gastric cancer patients that accept adjuvant postoperative randiaotherapy,therefore,3D split-field conformal radiaotherapy technique can be promoted.更多还原