Physics and Biology of FLASH Radiation

放射治疗是治疗癌症的有效手段。然而，放射治疗的全部潜力受到辐射也会损害健康组织这一事实的限制。为了避免对接受治疗的病人造成严重损害和痛苦，必须限制放射剂量。尽管对许多病人来说，更高的治疗剂量对于治愈他们来说是必要的。在用FLASH放射疗法治疗癌症时，所有的放射剂量都在几分之一秒内传递，比传统放射疗法快1000多倍。这种新的放射治疗技术在改善癌症治疗方面具有巨大的潜力，因为与标准放射治疗相比，它对健康组织的毒性较小，但对肿瘤治疗同样有效。然而，人们对这种非常有益的闪蒸效应背后的生物学过程知之甚少。我们有一个强大而灵活的线性加速器可用于实验。它能够提供FLASH放射治疗所需的强辐射场。通过进行不同的细胞、组织和小鼠实验，我们的目标是解释这种效果，并找出在我们的癌症治疗中心进行人体试验时如何最好地利用这种治疗技术。

Radiotherapy is an effective tool in the treatment of cancer. However, the full potential of radiotherapy is limited by the fact that radiation also damage healthy tissues. To avoid causing severe damage and suffering for patients receiving treatment, the radiation dose delivered must be limited. Even though, for many patients, a higher treatment dose would be necessary for curing them. In cancer treatment with FLASH radiotherapy, all the radiation dose is delivered in parts of a second, more than 1 000 times quicker than in conventional radiotherapy. This new radiotherapy technique has great potential in improving cancer treatment, as it is less toxic to healthy tissues compared to standard radiotherapy but as effective at treating tumours. However, very little is known about the biological processes behind this highly beneficial FLASH effect. We have a powerful and flexible linear accelerator available for experiments. It is capable of delivering the intense radiation fields needed for FLASH radiotherapy. By performing different cell, tissue, and mice experiments, we aim to explain the effect and to find out how to best take advantage of this treatment technique when moving towards human trials in our cancer treatment centres.