Gerdán Mercédesz, Pócza Tamás, Polgár Csaba, Major Tibor
Sugárterápiás Központ, Országos Onkológiai Intézet, Budapest, Hungary.
Magy Onkol. 2021 Mar 17;65(1):14-22. Epub 2020 Mar 17.
In treatment planning of small-sized lung tumors treated with stereotactic body radiotherapy (SBRT) in Eclipse treatment planning system with the Normal tissue objective (NTO) tool sharp dose gradients beyond the target volume can be achived. NTO has 5 variable parameters, so it is difficult to know which settings are optimal. The purpose of this study was to characterize the effects of changing NTO parameters on lung SBRT dose distributions. Ten lung SBRT cases were replanned using different NTO parameters. Dose calculation was performed using AAA and AXB algorithms as well. Differences between AAA and AXB plans were statistically significant. Plans were evaluated based on plan quality metrics. According to this analysis the fall-off of 0.15 and the priority of 500 have satisfied our institutional criteria best. Using NTO during planning is recommended in clinical practice.
在瓦里安Eclipse治疗计划系统中，使用立体定向体部放疗（SBRT）治疗小型肺肿瘤的治疗计划中，借助正常组织目标（NTO）工具可在靶区体积之外实现锐利的剂量梯度。NTO有5个可变参数，因此很难知道哪些设置是最佳的。本研究的目的是描述改变NTO参数对肺部SBRT剂量分布的影响。使用不同的NTO参数对10例肺部SBRT病例重新进行计划。剂量计算也使用AAA和AXB算法。AAA和AXB计划之间的差异具有统计学意义。根据计划质量指标对计划进行评估。根据该分析，0.15的剂量下降和500的优先级最符合我们机构的标准。建议在临床实践中计划制定时使用NTO。
