FLASH radiotherapy is considered a new potential breakthrough in cancer treatment. Ultra-high dose rates (>40 Gy/s) have been shown to reduce toxicity in the normal tissue without compromising tumor control, resulting in a widened therapeutic window. These high dose rates are more easily achievable in the clinic with charged particles, and clinical trials are, indeed, ongoing using electrons or protons. FLASH could be an attractive solution also for heavier ions such as carbon and could even enhance the therapeutic window. However, it is not yet known whether the FLASH effect will be the same as for sparsely ionizing radiation when densely ionizing carbons ions are used. Here we discuss the technical challenges in beam delivery and present a promising solution using 3D range-modulators in order to apply ultra-high dose rates (UHDR) compatible with FLASH with carbon ions. Furthermore, we will discuss the possible outcome of C-ion therapy at UHDR on the level of the radiobiological and radiation chemical effects.

中文翻译：

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碳离子束 FLASH 放射治疗

FLASH放疗被认为是癌症治疗的一个新的潜在突破。超高剂量率（>40 Gy/s）已被证明可以在不影响肿瘤控制的情况下降低正常组织的毒性，从而扩大治疗窗口。这些高剂量率在带电粒子的临床中更容易实现，而且临床试验实际上正在使用电子或质子进行。对于碳等较重的离子，FLASH 也可能是一种有吸引力的解决方案，甚至可以增强治疗窗口。然而，目前尚不清楚当使用密集电离碳离子时，FLASH 效应是否会与稀疏电离辐射相同。在这里，我们讨论了光束传输中的技术挑战，并提出了一种使用 3D 范围调制器的有前途的解决方案，以便应用与带有碳离子的 FLASH 兼容的超高剂量率 (UHDR)。此外，我们将讨论 UHDR 中 C 离子治疗在放射生物学和放射化学效应水平上的可能结果。