局部晚期胰头癌不同调强放疗技术的剂量学分析

摘要

目的:探讨局部晚期胰头癌应用不同放疗技术靶区及危及器官剂量学差异,改善局部晚期胰头癌的放射治疗技术.方法:对10例局部晚期胰头癌患者分别制定7野均分调强计划(7fIMRT)、5野均分调强计划(5fIMRT)和简易调强计划 (sIMRT),对这些计划的靶区及危及器官进行剂量分析.结果:1、3种计划的均匀指数比较:7fIMRT＜ sIMRT＜ 5fIMRT;sIMRT的治疗时间明显短于其余2种计划,其余2种计划之间无统计学差异.适形指数无统计学差异.2、各计划小肠V30无统计学差异,V40 5fIMRT低于7fIMRT(P＜ 0.05)；十二指肠V40水平3种计划无明显差异(P＞0.05),十二指肠接受的最大剂量Dmax以7fIMRT最低,其余2种计划无统计学差异.各计划中肝脏受照射剂量,V10sIMRT和5fIMRT均低于7fIMRT,V20、V30、V40、V50各个计划均无差异(P＞ 0.05)；7fIMRT右肾V20水平低于sIMRT,右肾V30水平各个计划均无统计学差异；左肾V20水平各个计划无统计学差异,V30水平7fIMRT低于5fIMRT及sIMRT;各个计划的脊髓剂量均满足目标函数要求,并无统计学差异.结论:1、sIMRT的治疗时间短,在肝脏的低剂量照射体积少,建议不能忍耐长时间治疗或肝功能受损的患者可选择sIMRT.2、7fIMRT的十二指肠最大剂量、右肾V20及左肾V30水平均优于其余2种计划,且具有最优的均匀性,对于肾功能差和消化道反应明显的患者可选择7fIMRT.%Objective:To perform a dosimetric comparison of different IMRT techniques for the target volume and OAR of locally advanced unresectable pancreatic adenocarcinoma,improve the radiotherapy technique for locally advanced unresectable pancreatic adenocarcinoma.Methods:10 patients with locally advanced unresectable pancreatic adenocarcinoma were respectively designed 7 equational fields IMRT plan (7fIMRT),5 equational fields IMRT plan (5fIMRT) and simplified IMRT plan (sIMRT),analysising the dosimetric comparison of the target volume and OAR.Results:l.The HI among the 3 plans:7fIMRT＜ sIMRT＜ 5fIMRT.In the treatment delivery time,the sIMRT plan was obviously shorter than the other two plans,but the left plans had no statistically significant difference.The CI of the three plans was not statistically significant different.2.At V30 of small intestine,there were no statistically significant difference in either plan.The V40 of 5fIMRT was superior to 7fIMRT.The Dmax of duodenum in 7fIMRT was better than the others,and the other two had no statistically significant difference . Both sIMRT and 5fIMRT had advantage over 7fIMRT in V10 of liver,but had no difference in themselves and V20、V30、V40、V50 (P＞ 0.05).The V20 of right kidney in 7fIMRT was better than that in sIMRT,but there were no significant differences in the other plans.The V30 of right kidney and the V20 of left kidney in the three plans had no significant differences.The V30 of left kidney was better than those were in 5fIMRT and sIMRT,and there were no significant differences in the other two plans.The dose of spinal cord in every plan was conformed with the objective functions and there were no significant differences.Conclusions:1.As the treatment delivery time of sIMRT was obviously short and it had advantage in low dose in liver,it was suggested that sIMRT was suitable for the patients who could not endure long treatment time or patients with hepatic dysfunction.2、7fIMRT was superior to the other plans in Dmax of duodenum 、V20 of fight kidney and V30 of left kidney,and what's more it had a better HI.So 7fIMRT was applied to the patients with renal inadequacy and digestive tract responses.