Product Development of Intensity Modulation for Bolus Electron Conformal Therapy

推注电子适形治疗强度调制产品开发

• 批准号: 9199469
• 负责人: Kevin James Erhart
• 金额: $ 26.11万
• 依托单位: DECIMAL, INC.
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-13 至 2018-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9199469
• 关键词: Acute; Agreement; Air; Algorithms; Area; Bolus Infusion; Caliber; Cancer Control; Collimator; Computer software; Conformal Radiotherapy; Copper; Devices; Distal; Dose; Electron Beam; Electron Beam Therapy; Electrons; Goals; Guidelines; Heterogeneity; Island; Location; Malignant Neoplasms; Measurement; Measures; Methods; Mission; Modality; Modeling; Monte Carlo Method; Normal tissue morphology; Patients; Pattern; Penetration; Phase; Radiation; Radiation Oncologist; Radiation therapy; Reporting; Research; Risk; Second Primary Cancers; Site; Small Business Technology Transfer Research; Surface; System; Techniques; Technology; Testing; Time; Tissues; Variant; Water; abstracting; cancer therapy; density; design; improved; product development; quality assurance; radiation adverse effect; software development; tool; treatment planning

Project Summary/Abstract Electron beam therapy (EBT) using 6-20 MeV beams provides effective radiation treatment for superficial cancers (depth<6 cm). As many as 20% of radiotherapy patients (166,000 in USA annually) are eligible for electron therapy for some portion of their treatment, making it the second most used external beam modality. As many as 10% of these electron patients (16,600 annually) could benefit from bolus electron conformal therapy (ECT), a technique conforming the dose distribution (distal 90% isodose surface) to the targeted cancer volume while protecting surrounding healthy tissue from acute and long-term adverse effects of radiation, aligning with the agency mission to improve cancer treatment quality. Currently, radiation oncologists are limited in the use of bolus ECT because of dose heterogeneity (as great as 30%) in the targeted cancer volume due to multiple Coulomb scattering from the irregular proximal bolus surface. This Phase I application proposes to research and develop electron intensity modulation technology (planning software and delivery device), which when integrated with existing bolus ECT technology, can eliminate the dose heterogeneity problem, i.e., deliver a more uniform dose distribution (10% dose spread) to the targeted cancer volume. Availability of the proposed product, intensity modulated bolus ECT, should not only greatly improve current treatments of superficial cancers using electron radiotherapy (bolus ECT or otherwise), but in some cases provide an improved alternative to other radiation modalities (e.g. volumetric arc therapy or intensity modulated radio-therapy) by having (1) decreased chance of secondary cancers, (2) equally high chance of cancer control, and (3) equally low chance of acute normal tissue complications. The proposed delivery technology is an intensity modulator plate, which consists of a matrix of small-diameter, cylindrical island blocks imbedded in a low-density slab attached to the beam-defining, collimating insert. The magnitude of the intensity modulation is related to the fraction of beam area covered by the island blocks in a small overlying region. By properly varying the diameter and/or separation of these island blocks, electron scatter in air should result in a smoothly varying intensity pattern on the patient and/or bolus that restores the dose uniformity in the cancer target volume when using bolus ECT. Phase I goals will be to demonstrate proof of principle by (1) incorporating intensity modulation into the existing BolusECT software product, including a method for ‘segmenting’ the intensity pattern into an appropriate matrix of island blocks, (2) validating that the planning software modeling the island blocks produces expected results for select patient sites, and (3) validating delivery of the planned intensity modulated BolusECT beams by demonstrating agreement between delivered (measured) and planned (calculated) dose distributions in water.

项目摘要/摘要 使用6-20 MEV梁的电子束疗法（EBT）为表面提供有效的辐射治疗 癌症（深度<6厘米）。多达20％的放疗患者（美国每年16.6万）有资格 电子疗法的一部分治疗，使其成为第二使用的外部梁 方式。这些电子患者中多达10％（每年16,600）可以从推注电子中受益 共形治疗（ECT），一种符合剂量分布（远端90％异源表面）的技术 靶向癌症的同时保护周围健康组织免受急性和长期不良 辐射的影响，与改善癌症治疗质量的机构任务保持一致。现在， 辐射肿瘤学家在使用剂量异质性（高达30％）的使用中受到限制 由于从不规则的近端推注表面散射多个库仑引起的靶向癌症。 该阶段I应用程序用于研究和开发电子强度调制技术 （规划软件和交付设备），当与现有的推注技术集成时，可以 消除剂量异质性问题，即提供更均匀的剂量分布（10％剂量扩散） 到靶向癌症。提议的产品的可用性，强度调节的推注，应 不仅可以通过电子放射疗法（losus ect或 否则），但是在某些情况下，可以改善其他辐射方式（例如体积 通过（1）次级癌症的机会降低（2），ARC治疗或强度调制放射治疗） 癌症控制的机会同样很高，（3）急性正常组织并发症的机会同样很低。 拟议的输送技术是强度调制板，由 小直径，圆柱岛块嵌入了横梁定义的低密度平板中 准直插入。强度调制的大小与覆盖的光束面积的比例有关 在一个小型地区的岛屿街区。通过正确改变这些直径和/或分离 岛屿块，空气中的电子散射应导致患者的强度平滑变化 和/或推注时，使用推注ECT恢复癌症靶标体积中的剂量均匀性。 第一阶段目标是通过（1）将强度调制纳入到 现有的Bolusect软件产品，包括一种将强度模式“分割”到一个的方法 适当的岛屿区块矩阵，（2）验证了对岛屿块建模的计划软件 为精选的患者站点产生预期结果，（3）验证计划强度的交付 通过证明已交付（测量）和计划之间的一致的一致性，调制了Bolusect的梁 （计算）水中的剂量分布。