PDF(Pubmed)
Abstract：
FLASH-radiotherapy delivers a radiation beam a thousand times faster compared to conventional radiotherapy, reducing radiation damage in healthy tissues with an equivalent tumor response. Although not completely understood, this radiobiological phenomenon has been proved in several animal models with a spectrum of all kinds of particles currently used in contemporary radiotherapy, especially electrons. However, all the research teams have performed FLASH preclinical studies using industrial linear accelerator or LINAC commonly employed in conventional radiotherapy and modified for the delivery of ultra-high-dose-rate (UHDRs). Unfortunately, the delivering and measuring of UHDR beams have been proved not to be completely reliable with such devices. Concerns arise regarding the accuracy of beam monitoring and dosimetry systems. Additionally, this LINAC totally lacks an integrated and dedicated Treatment Planning System (TPS) able to evaluate the internal dose distribution in the case of in vivo experiments. Finally, these devices cannot modify dose-time parameters of the beam relevant to the flash effect, such as average dose rate; dose per pulse; and instantaneous dose rate. This aspect also precludes the exploration of the quantitative relationship with biological phenomena. The dependence on these parameters need to be further investigated. A promising advancement is represented by a new generation of electron LINAC that has successfully overcome some of these technological challenges. In this review, we aim to provide a comprehensive summary of the existing literature on in vivo experiments using electron FLASH radiotherapy and explore the promising clinical perspectives associated with this technology.
摘要：
与传统放射治疗相比，FLASH放射治疗的辐射束速度是传统放射治疗的一千倍，减少健康组织中的辐射损伤，具有等效的肿瘤反应。虽然没有完全理解，这种放射生物学现象已经在几种动物模型中得到了证明，目前在当代放射治疗中使用的各种粒子的光谱，尤其是电子。然而,所有研究团队都使用工业直线加速器或LINAC进行了FLASH临床前研究,这些研究通常用于常规放射治疗,并为超高剂量率(UHDR)的递送进行了改良.不幸的是,UHDR光束的传递和测量已被证明是不完全可靠的与这样的设备。人们对光束监测和剂量测定系统的准确性感到担忧。此外,该LINAC完全缺乏能够在体内实验的情况下评估内部剂量分布的集成和专用治疗计划系统（TPS）。最后,这些设备不能修改与闪光效应相关的光束的剂量-时间参数，例如平均剂量率;每脉冲剂量;和瞬时剂量率。这方面也排除了与生物现象的定量关系的探索。对这些参数的依赖性需要进一步研究。新一代电子LINAC成功克服了其中一些技术挑战，这是一个有希望的进步。在这次审查中,我们的目标是提供现有的关于使用电子FLASH放射治疗的体内实验的文献的全面总结，并探索与该技术相关的有希望的临床观点。
