胰腺癌三维适形放疗计划剂量学的比较与研究

目的：探讨胰腺癌三维适形放疗中三野、四野、三野交叉3种不同治疗计划的优缺点。方法：10例胰腺癌患者采用3D-CRT方法,在同一治疗计划系统中,设计三野、四野、三野交叉等3种适形放疗方案,总剂量60 Gy,应用剂量-体积直方图（DVH）评价PTV、正常组织受量、对比研究3种治疗计划的特点。结果：3种治疗方法在靶区适形度及受量上差异不显著,但三野技术在保护脊髓上优于其他2种照射方法,在肝脏及脾脏的保护上无明显差异,在保护双肾上与其他2种方法相比有所欠缺。结论：根据靶体积及肿瘤部位的不同,采用不同的计划方法。胰头部肿瘤因离肠道及肝脏较近,一般采用三野或四野技术;而胰尾部肿瘤因离胃部较近,一般采用三野交叉技术。

Posology Comparison and Research of Three-dimensional Conformal Radiotherapy for Pancreatic Cancers

Objective To explore the advantages and disadvantages of three different treatment plans（three-field,four-field,three-field crossing） in three-dimensional conformal radiotherapy for pancreatic cancers.Methods For 10 patients with pancreatic cancer and received radiation therapy,three-field,four-field,three-field crossing treatment plans were designed with a total dose of 60Gy in the same treatment planning system.PTV and the tolerated dose of normal tissues were analyzed based on the DVH dose volume histogram,by which the three treatment plans were compared.Results The difference of conformity in target and tolerated dose of the three treatment plans were not clear.The three-field crossing was better than the other two plans in protecting spinal marrow,but there was almost no difference in protecting liver and spleen.It was worse than the other two plans in protecting kidneys.Conclusion According to the target volume and the location of the tumor,different treatment plans should be applied.For the tumors in the head of the pancreas which near to the intestine and liver,four-field or three-field crossing are usually applied;while for the tumors in the end of the pancreas which near to the stomach,the three-field crossing is usually used.