肺组织校正与否对肿瘤放疗剂量分布影响的研究  

Study of the Impact of Correction or Non-correction for Lung Tissue on Dose Distribution

作　　者：滕炳祥[1] 曾自力[1] 刘兵[1] 

机构地区：[1]柳州市柳铁中心医院肿瘤科,柳州市545007

出　　处：《广西医学》2012年第2期166-169,共4页Guangxi Medical Journal

基　　金：广西医疗卫生科研课题(桂卫Z2011241)

摘　　要：目的比较不均匀肺组织校正与否对肺癌患者的肿瘤靶区、正常组织及重要器官放疗剂量分布的影响。方法 9例原发性肺癌患者,每例均同时设计两种治疗计划,即常规放疗不校正不均匀肺组织计划(计划1)、三维适形放疗(3DCRT)校正不均匀肺组织计划(计划2)。计划1为前后对穿照射60 Gy,通过调节剂量权重使处方剂量与常规放疗相同;射野大小及其他参数与常规放疗相同,此时得到计划1的剂量分布就是常规不校正不均匀肺组织在患者体内的实际分布。计划2为3DCRT照射60 Gy。将计划1与计划2进行比较。结果计划2的Dmax、Dmin和Dmean PTV剂量小于计划1,差异有统计学意义(P<0.05);计划1HI、CI值小于计划2,差异有统计学意义(P<0.05);脊髓Dmax计划1高于计划2、食管V50则计划1少于计划2,两肺V20、V5均为计划2高于计划1,差异有统计学意义(P<0.05);心脏V40、Dmean差异无统计学意义(P>0.05)。结论 3DCRT校正不均匀肺组织比常规放疗不校正不均匀肺组织对肺癌患者的肿瘤靶区剂量分布有明显保证和改善,但对正常组织和重要器官的受量有一定程度增加。To compare the impact of correction or noncorrection for heterogeneous lung tissue on the dose distribution of tumor target, normal tissue and organs at risk of patients with lung cancer. Methods Night cases of primary lung cancer were enrolled in the study. Two radiotherapy plans were designed for each case ： plan of noncorrection in routine radiotherapy for heterogeneous lung tissue （ plan 1 ） , plan of correction in 3-dimensional conformal radiotherapy （3 DCRT） for heterogeneous lung tissue （ plan 2）. Plan 1 included 60 Gy irradiation for anterior and posterior fields, making prescription dose same as that of the routine radiotherapy by adjusting the dose weight, and the irradiation field size and other parameters same as those of the routine radiotherapy. Then the dose distribution of plan 1 was the actual distribution in the patient＇s body at the moment. Plan 2 included 60 Gy irradiation of 3DCRT. The dose distributions of plan 1 and plan 2 were compared. Results Dmax, Dmin and Dmean of PTV of plan 2 were lower than those of planl, and there were significantly different （P 〈 0.05 ）. Values of HI and CI of plan 1 were smaller than those of plan 2, and there were significantly different （P 〈 0.05）. Dmax of spinal cord of plan 1 was higher than that of plan 2, esophagus V50 of plan 1 was smaller than that of plan 2, the V20 and V5 of two lungs of plan 2 were higher than those of plan 1, and there were significant differences （ P 〈 0.05 ）. No significant difference was found in heart V40 and Dmean between the two plans （ P 〉 0.05 ）. Conclusion Compared with noncorrection in routine radiotherapy, correction in 3DCRT for heterogeneous lung tissue provides more guarantee and improvement for the dose distribution of tumor target in patients with lung cancer, and makes the irradiation dose of the normal tissue and organs at risk increase.

关 键 词：肺癌 放射疗法 三维适形 剂量分布 

分 类 号：R730.55[医药卫生—肿瘤]