蒋海兰,黄慧娴,刘 绪.鼻咽癌调强放疗时颈部临床靶区优化对甲状腺剂量学的影响研究[J].肿瘤学杂志,2021,27(11):926-932.
鼻咽癌调强放疗时颈部临床靶区优化对甲状腺剂量学的影响研究
Effect of Optimization of Cervical Target Volume on Dosimetric Distribution for the Thyroid During Intensity-Modulated Radiotherapy for Nasopharyngeal Carcinoma
投稿时间:2021-06-25  
DOI:10.11735/j.issn.1671-170X.2021.11.B006
中文关键词:  鼻咽肿瘤  甲状腺  调强放射治疗  剂量优化
英文关键词:nasopharyngeal carcinoma  thyroid  intensity?鄄modulated radiation therapy  dose optimization
基金项目:
作者单位
蒋海兰 广西壮族自治区人民医院 
黄慧娴 广西壮族自治区人民医院 
刘 绪 广西壮族自治区人民医院 
摘要点击次数: 1048
全文下载次数: 242
中文摘要:
      摘 要:[目的] 探讨在鼻咽癌调强放射治疗(IMRT)时对颈部临床靶区进行剂量优化,在不影响靶区覆盖及危及器官的受照剂量的前提下对甲状腺是否有剂量学获益。[方法] 选取29例已行根治性IMRT的鼻咽癌患者,调取定位CT图像,勾画靶区及危及器官(包括甲状腺),分别设计两种调强计划,不对颈部Ⅳ区优化组(参照ICRU50和62号报告进行勾画,包含整个Ⅳ区)和对颈部Ⅳ区优化组(甲状腺出现的区域只包括颈内静脉周围部分)的计划。甲状腺剂量限制参数:Dmean<45 Gy、V30<62.5%和V45<50%。当靶区剂量覆盖与甲状腺的剂量限定不能同时满足时优先保证靶区足够的剂量覆盖。[结果] 两种计划各靶区95%处方剂量的体积、适形指数和剂量均匀性指数间差异无统计学意义,PTVnx和 PTVnd大于110%处方剂量的体积也无统计学差异。两种计划中PTV2的V93有统计学差异(P=0.017),但两种计划均满足接受<93%处方剂量的体积<1%的目标要求。对颈部靶区进行优化后可以显著性降低甲状腺最大剂量、最小剂量、平均剂量、V20、V26、V30、V35、V40、V45、V50、V55以及V60。两组间甲状腺V10、V15和V65差异无统计学意义。淋巴结分期N0~1期和N2~3期患者对颈部临床靶区进行优化后,与未进行优化相比,甲状腺最小剂量、平均剂量、V26、V30、V35、V40、V45、V50和V55显著性减少(P均<0.05),且当淋巴结为N2~3期时,甲状腺最大剂量也明显减少(P=0.013)。[结论] 鼻咽癌在IMRT计划设计时,在保证靶区足够的剂量覆盖且不影响其他危及器官受照剂量的前提下,对颈部Ⅳ区进行优化可减少甲状腺的受照剂量和受照体积。
英文摘要:
      Abstract: [Objective] To investigate the effect of optimization of cervical clinical target volume on dosimetric distribution of the thyroid during intensity-modulated radiotherapy(IMRT) for nasopharyngeal carcinoma(NPC). [Methods] Twenty-nine NPC patients treated with IMRT were enrolled in the study. Targets and organs at risk(including the thyroid) were delineated on the simulation CT. Two IMRT plans for each patient were designed. The plan1 did not optimize clinical volume involving level Ⅳ of the neck, which covered the entire area of level Ⅳ in accordance with the International Commission on Radiation Units and Measurements Reports 50 and 62. The plan2 optimized clinical target volume of level Ⅳ of the neck, in which the target area only included the peripheral part of the internal jugular vein where the thyroid appeared in the simulation CT. The dose constraints for the thyroid were as follows: Dmean<45 Gy, V30<62.5% and V45<50%. The target dose coverage should be prioritized when it conflicted with thyroid dose limitation. [Results] No significant differences were found in the percentage of volume of the PTVs receiving 95% of the prescribed dose(V95), conformity index and homogeneity index and in the percentage of the volume of PTVnx and PTVnd receiving more than 110% of the prescribed dose(V110) between two plans. Both plans met the requirement that the percentage of the volume of PTV2 receiving 93% prescribed dose was <1%, although significant difference of V93 in PTV2 between the two plans was found(P=0.017). The maximum dose, minimum dose, average dose, V20, V26, V30, V35, V40, V45, V50, V55 and V60 were significantly reduced after optimizing the clinical target area of the neck. There was no significant difference in V10, V15 and V65 for the thyroid between two plans. The minimum dose, mean dose, V26, V30, V35, V40, V45, V50, and V55 for the thyroid were significantly reduced after optimization when lymph node stages were N0~1 and N2~3(all P<0.05), and the maximum dose of thyroid was also significantly reduced when lymph node stages were N2~3(P=0.013). [Conclusion] The radiation dose and volume of the thyroid during IMRT for NPC patients can be reduced significantly after optimization of clinical target volume of level Ⅳ of the neck without compromising adequate dose
在线阅读   查看全文  查看/发表评论  下载PDF阅读器