...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Acta oncologica. >A study of the beam-specific interplay effect in proton pencil beam scanning delivery in lung cancer
【24h】

A study of the beam-specific interplay effect in proton pencil beam scanning delivery in lung cancer

机译：质子铅笔梁扫描递送在肺癌中的比光束相互作用研究

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Background: For lung tumors with large motion amplitudes, the use of proton pencil beam scanning (PBS) can produce large dose errors. In this study, we assess under what circumstances PBS can be used to treat lung cancer patients who exhibit large tumor motion, based on the quantification of tumor motion and the dose interplay.Material and methods: PBS plans were optimized on average 4DCT datasets using a beam-specific PTV method for 10 consecutive patients with locally advanced non-small-cell-lung-cancer (NSCLC) treated with proton therapy to 6660/180 cGy. End inhalation (CT0) and end exhalation (CT50) were selected as the two extreme scenarios to acquire the relative stopping power ratio difference (rsp) for a respiration cycle. The water equivalent difference (WET) per radiological path was calculated from the surface of patient to the iCTV by integrating the rsp of each voxel. The magnitude of motion of voxels within the target follows a quasi-Gaussian distribution. A motion index (MI (5mm WET)), defined as the percentage of target voxels with an absolute integral WET larger than 5mm, was adopted as a metric to characterize interplay. To simulate the treatment process, 4D dose was calculated by accumulating the spot dose on the corresponding respiration phase to the reference phase CT50 by deformable image registration based on spot timing and patient breathing phase.Results: The study indicated that the magnitude of target underdose in a single fraction plan is proportional to the MI (p.001), with larger motion equating to greater dose degradation and standard deviations. The target homogeneity, minimum, maximum and mean dose in the 4D dose accumulations of 37 fractions varied as a function of MI.Conclusions: This study demonstrated that MI can predict the level of dose degradation, which potentially serves as a clinical decision tool to assess whether lung cancer patients are potentially suitable to receive PBS treatment.
机译：背景：对于具有大型运动幅度的肺肿瘤，使用质子铅笔扫描（PBS）可以产生大剂量误差。在这项研究中，我们在什么情况下评估PBS可用于治疗表现出大型肿瘤运动的肺癌患者，基于肿瘤运动的量化和剂量相互作用。材料和方法：PBS计划在平均4DCT数据集上优化了射频PTV方法为10名局部晚期非小细胞 - 肺癌（NSCLC）的连续患者，用质子疗法治疗到6660/180 CGY。选择最终吸入（CT0）和最终呼气（CT50）作为两个极端场景，以获取呼吸周期的相对停止功率比差（RSP）。通过整合每个体素的RSP，从患者的表面从患者的表面计算每个放射性路径的水当量差（湿）。目标内体素的运动幅度遵循拟高斯分布。采用运动指数（MI（＆ 5mm湿）），被定义为具有大于5mm的绝对积分湿的靶体素百分比，作为指标以表征相互作用。为了模拟处理过程，通过基于点定时和患者呼吸阶段，通过可变形的图像配准通过可变形的图像配准通过将点剂量积聚到参考阶段CT50对参考相CT50来计算4D剂量。结果：该研究表明，该研究表明靶标的幅度单个级分计划与Mi（P <.001）成比例，具有较大的运动等于更大的剂量降解和标准偏差。 4D剂量均匀性，最小，最大和平均剂量为37分数的函数变化为Mi.Conclusions：本研究证明MI可以预测剂量降解水平，这可能是评估的临床决策工具肺癌患者是否可能适合接受PBS治疗。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号