Narayanasamy Ganesh, Stathakis Sotirios, Gutierrez Alonso N, Pappas Evangelos, Crownover Richard, Floyd John R, Papanikolaou Niko
1 Department of Radiation Oncology, University of Texas Health Science Center at San Antonio, TX.
2 Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR.
Technol Cancer Res Treat. 2017 Oct;16(5):639-644. doi: 10.1177/1533034616666998. Epub 2016 Sep 9.
In this treatment planning study, we compare the plan quality and delivery parameters for the treatment of multiple brain metastases using 2 monoisocentric techniques: the Multiple Metastases Element from Brainlab and the RapidArc volumetric-modulated arc therapy from Varian Medical Systems.
Eight patients who were treated in our institution for multiple metastases (3-7 lesions) were replanned with Multiple Metastases Element using noncoplanar dynamic conformal arcs. The same patients were replanned with the RapidArc technique in Eclipse using 4 noncoplanar arcs. Both techniques were designed using a single isocenter. Plan quality metrics (conformity index, homogeneity index, gradient index, and R), monitor unit, and the planning time were recorded. Comparison of the Multiple Metastases Element and RapidArc plans was performed using Shapiro-Wilk test, paired Student t test, and Wilcoxon signed rank test.
A paired Wilcoxon signed rank test between Multiple Metastases Element and RapidArc showed comparable plan quality metrics and dose to brain. Mean ± standard deviation values of conformity index were 1.8 ± 0.7 and 1.7 ± 0.6, homogeneity index were 1.3 ± 0.1 and 1.3 ± 0.1, gradient index were 5.0 ± 1.8 and 5.1 ± 1.9, and R were 4.9 ± 1.8 and 5.0 ± 1.9 for Multiple Metastases Element and RapidArc plans, respectively. Mean brain dose was 2.3 and 2.7 Gy for Multiple Metastases Element and RapidArc plans, respectively. The mean value of monitor units in Multiple Metastases Element plan was 7286 ± 1065, which is significantly lower than the RapidArc monitor units of 9966 ± 1533 ( P < .05).
For the planning of multiple brain lesions to be treated with stereotactic radiosurgery, Multiple Metastases Element planning software produced equivalent conformity, homogeneity, dose falloff, and brain V but required significantly lower monitor units, when compared to RapidArc plans.
在这项治疗计划研究中，我们比较了使用两种单等中心技术治疗多发性脑转移瘤的计划质量和剂量输送参数：Brainlab公司的多发性转移瘤模块（Multiple Metastases Element）和瓦里安医疗系统公司的容积调强弧形治疗（RapidArc）。
对在我院接受治疗的8例多发性转移瘤（3 - 7个病灶）患者，使用非共面动态适形弧，采用多发性转移瘤模块重新制定计划。对同一批患者，在Eclipse中使用4个非共面弧，采用RapidArc技术重新制定计划。两种技术均采用单一等中心设计。记录计划质量指标（适形指数、均匀性指数、梯度指数和R）、监测单位和计划时间。采用Shapiro-Wilk检验、配对t检验和Wilcoxon符号秩检验对多发性转移瘤模块和RapidArc计划进行比较。
多发性转移瘤模块和RapidArc之间的配对Wilcoxon符号秩检验显示，计划质量指标和脑剂量相当。多发性转移瘤模块计划和RapidArc计划的适形指数平均值±标准差分别为1.8±0.7和1.7±0.6，均匀性指数分别为1.3±0.1和1.3±0.1，梯度指数分别为5.0±1.8和5.1±1.9，R分别为4.9±1.8和5.0±1.9。多发性转移瘤模块计划和RapidArc计划的平均脑剂量分别为2.3 Gy和2.7 Gy。多发性转移瘤模块计划的监测单位平均值为7286±1065，显著低于RapidArc的监测单位9966±1533（P <.05）。
对于采用立体定向放射外科治疗的多发性脑病灶计划，与RapidArc计划相比，多发性转移瘤模块计划软件产生的适形性、均匀性、剂量下降和脑V相当，但所需的监测单位显著更低。
