胃癌术后辅助放疗不同照射技术的剂量学对比研究  

Dosimetric study of three different techniques in postoperative adjuvant irradiation of gastric carcinoma

作　　者：熊华[1] 陈元[1] 邹燕梅[1] 于世英[1] 王俊峰[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院肿瘤中心,湖北武汉430030

出　　处：《中华肿瘤防治杂志》2009年第21期1686-1690,共5页Chinese Journal of Cancer Prevention and Treatment

摘　　要：目的:比较胃癌术后常规放疗(CRT)、三维适形放疗(3D-CRT)和调强适形放疗(IMRT)对靶区剂量分布及周围正常组织的影响,探讨胃癌术后放疗较理想的治疗模式。方法:选择15例胃癌术后患者,每例各设计3种放射治疗计划:CRT、3D-CRT及IMRT。规定临床靶体积(PTV)接受≥95%处方剂量(45Gy)。比较靶区相关参数D95、V95、适形指数(CI)及肾脏、肝脏和脊髓受照射剂量-体积和正常组织并发症概率(NTCP)的差异。结果:1)3种照射模式的D95、V95及CI的均值分别为44.5、44.9和44.5Gy;98.3%、98.7%和98.2%;0.84、0.85和0.83,三者差异均无统计学意义,P>0.05;2)比较双肾在低剂量区(5～10Gy)受照射体积,CRT明显低于3D-CRT及IMRT(P<0.05)。采用IMRT后明显降低中高剂量区(15～47.5Gy)肾脏体积,P<0.05;3)IMRT明显降低肝脏30～47.5Gy剂量区受照射体积(P<0.05),但在低剂量区(V5～V25)稍高于CRT和3D-CRT(P>0.05);4)3种计划中脊髓低剂量区(5～25Gy)受照射体积差异无统计学意义,P>0.05,而在V30～V45区域CRT明显偏低,P<0.05;5)比较肝脏和双肾并发症概率,IMRT<3D-CRT<CRT;其中肝脏和左肾的差异有统计学意义,P<0.05。结论:CRT、3D-CRT和IMRT均能保证靶区剂量理想分布。IMRT与其他照射技术相比具有较明显的剂量学优势,能有效降低肝脏及肾脏受照剂量和降低正常组织并发症概率。OBJECTIVE：To assess the characteristics of intensity-modulated radiation therapy（IMRT）,3-dimension conformal radiotherapy（3D-CRT）and conventional radiotherapy（CRT）plans in patients with gastric carcinoma.METHODS：Fifteen for each patient data set,the 3 plans were replanned with a prescribed dose of 45 Gy to at least 95% of PTV.The dose distributions,DVH of OARs,conformity index（CIPTV）and normal tissue complication probability were compared for each plan.RESULTS：1）The D95 CI,V95 for IMRT,3D-CRT and CRT were 44.5 Gy,44.9 Gy,44.5 Gy and 98.3%,98.7%,98.2% and 0.84,0.85,0.83 respectively;the 3 plans could generally meet the demand of dose-volume constrains for PTV,P〉0.05.2）The low-dose volume（5-10 Gy）of bilateral irradiated kidneys in CRT was significantly lower than 3D-CRT and IMRT,but IMRT for 15-47.5 Gy,P〈0.05.3）With IMRT,the high-dose volume（V30-V47.5）of irradiated liver was significantly decreased（P〈0.05）.However,the low dose volume（V5-V25）was slightly increased（P〉0.05）.4）No significant difference in cord sparing was seen at the dose levels from 5-25 Gy in the 3 plans,but CRT significantly reduced the high dose volume（V30-V45 area）of irradiated cord（P〈0.05）.5）For the liver and bilateral kidneys＇ complication probability,IMRT3D-CRTCRT,especially for liver and left kidney.CONCLUSION：IMRT,3D-CRT,and CRT show the similar effect on PTV does coverage.Compared with 3D-CRT and CRT,IMRT leads to further incremental improvements in the left kidney and liver dose.

关 键 词：胃肿瘤/放射疗法 放射疗法 适形 放射治疗剂量 对比研究 

分 类 号：R735.2[医药卫生—肿瘤]