鼻咽癌四野面颈联合野适形放疗技术及剂量学研究  

Technical and dosimetric study of four facio-cervical fields conformal radiotherapy for nasopharyngeal carcinoma

作　　者：王方正[1] 付真富[1] 王磊[1] 朴永锋[1] 花永虹[1] 祝成龙[2] 徐敏[2] 陈伟军[2] 

机构地区：[1]浙江省肿瘤医院放疗科,杭州310022 [2]浙江省肿瘤医院物理室,杭州310022

出　　处：《浙江医学》2011年第6期794-796,799,共4页Zhejiang Medical Journal

基　　金：浙江省卫生厅科研基金项目（2009B026）

摘　　要：目的 研究鼻咽癌四野面颈联合野适形放疗技术建立方法,进行三维剂量学研究,寻找最佳临床应用方法.方法 选取40例经病理证实的初治鼻咽癌患者（T1、T2、T3、T4期各10例）,采用三维治疗计划系统设计照射方案.每例患者均设计2个方案：（1）以前后面颈野和双侧面颈联合野为主的常规外照射方案（四野面颈联合野适形方案）;（2）以双侧面颈联合野为主的常规外照射方案（传统方案）.每例患者的2个方案照射剂量相同,采用剂量体积直方图及截面剂量分布比较鼻咽癌以两种方案治疗时靶区、脑干、脊髓、晶体、颞叶、中耳、腮腺及颞颌关节的受照体积和剂量.结果 （1）四野面颈联合野适形方案可满足鼻咽和颈部计划靶体积的剂量要求;（2）两种方案脊髓受照剂量无明显差异,而四野面颈联合野适形方案脑干平均受照剂量高于传统方案,但并未超量;（3）四野面颈联合野适形方案双侧腮腺和颞颌关节受照剂量、分割剂量和被高剂量覆盖的体积均明显低于传统方案.结论 相对于传统方案,四野面颈联合野适形方案靶体积在获得满意剂量覆盖的同时可更好地保护腮腺、颞颌关节、颞叶等正常组织.Objective To establish and optimize the methods of four-field conformal radiotherapy（4F-CRT） for nasopharyngeal carcinoma （NPC）. Methods Forty patients with untreated NPC of T1 - T4 （1992 Fuzhou Staging System） were enrolled in this study. Conventional and four-field conform plans （improved plan） were designed for each patient using 3D-TPS. The improved plan included anterior facio-cervical and two lateral opposing facio-cervical fields; the conventional plan had two lateral opposing facio-cervical fields only. Both plans had the same dose delivered to the target of each patient. Dose volume histograms （DVHs） of the targets and normal organs, brain stem, spinal cord, parotid glands, and temporal mandibular joints （TMJs） were compared and the dose distributions were evaluated.Results The dose distribution of the improved plan met the requirements for the target volume. There was no significant difference in the dose of spinal cord between the two plans. The mean dose of Dmax for brain stem in conventional plan was much lower than those in the improved plan, though both were within safety Jimits. Compared with the conventional plans, the improved plan significantly decreased the hotspot areas in the target volume and had better parotid glands and temporal mandibular joints sparing effect.Conclusion Compared with the conventional plan, the improved plan provides satisfactory dose coverage to the target volume and better sparing of the parotid gland, TMJs and other normal organs in external beam radiotherapy of NPC.

关 键 词：鼻咽恶性肿瘤 四野适形放疗 剂量学 

分 类 号：R730.55[医药卫生—肿瘤]