Dose-Rate Variations for Patient Treatments in Flash and conventional radiation therapy

快速放射治疗和常规放射治疗中患者治疗的剂量率变化

• 批准号: 10405553
• 负责人: Jan Patrick Oscar Schuemann
• 金额: $ 19.24万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10405553
• 关键词: 3-Dimensional; Address; Biological; Biological Process; Biology; Chemicals; Chemistry; Clinical; Complication; Dependence; Dose; Dose-Rate; External Beam Radiation Therapy; Intensity modulated proton therapy; Maps; Methods; Modality; Monte Carlo Method; Normal tissue morphology; Outcome; Oxygen; Patients; Photons; Physics; Physiologic pulse; Play; Positioning Attribute; Primary Lesion; Protons; Quality of life; Radiation therapy; Reporting; Research; Role; Rotation; Scanning; Spottings; Structure; System; Time; Tissues; Translations; Treatment Protocols; Water; base; cancer therapy; clinical practice; design; experimental study; flexibility; improved; interest; irradiation; nanoscale; nanosecond; next generation; optimal treatments; patient variability; proton therapy; radiation response; side effect; standard care; time interval; treatment effect; treatment planning; treatment site; tumor

Radiation therapy has been an important component in the treatment of cancer for many decades. While the parameters of tumor control have been relatively well understood, normal tissue complication proba- bilities (NTCPs) are often only thought of as constraining factors in the design of a treatment regimen. However, with continuously improving treatments of primary lesions, NTCP and their impact on the quality of life have moved into the focus of research. One of the most prominent methods reported to spare healthy tissue is FLASH radiation therapy, i.e. ul- trafast (>40 Gy/s) irradiations, which reportedly results in incredible tissue sparing effects without com- promising efficacy for tumor cure. Conversely, very low dose-rate irradiations have also been reported to offer protective features. Together, these experiments suggest that the current clinical routine, treating patients with a medium dose-rate of ~2 Gy/min, could in fact be the least favorable when considering healthy tissue side effects. In clinical practice, patients are treated with a variety of radiation treatment modalities. While the result- ing target doses are similar across modalities, the dose delivered to the normal tissue and the time struc- ture of the delivery can vary significantly. Despite the range of dose-rates across treatment plans, the biological effect is estimated only based on the total dose received. We hypothesize that dose-rate plays an important role in the outcome of radiation therapy that can be exploited for specific treatment scenarios. For extreme cases such as FLASH therapy, averaged dose- rates do not capture the relevant time structures adequately. We will apply Monte Carlo simulations to determine time structures from the clinical scale of minutes (spot scanning / gantry rotation time) to na- noseconds (intra-spot delivery time) and assess potential effects on healthy tissue sparing that would im- prove the quality of life for radiation therapy patients.

几十年来，放射治疗一直是癌症治疗的重要组成部分。尽管 肿瘤控制的参数已被相对较好地理解，正常组织并发症的可能性 能力（NTCP）通常仅被认为是治疗方案设计中的限制因素。 然而，随着原发病灶治疗方法的不断改进，NTCP及其对 生活质量已成为研究的焦点。 据报道，保护健康组织的最重要方法之一是 FLASH 放射治疗，即 ul- trafast (>40 Gy/s) 照射，据报道，这会产生令人难以置信的组织保护效果，而无需 有望治愈肿瘤。相反，也有报道称极低剂量率照射 提供保护功能。总之，这些实验表明，当前的临床常规、治疗 中等剂量率约为 2 Gy/min 的患者在考虑时实际上可能是最不有利的 健康组织的副作用。 在临床实践中，患者接受多种放射治疗方式。而结果—— 各种方式的目标剂量相似，递送到正常组织的剂量和时间结构 交付的真实性可能会有很大差异。尽管治疗计划的剂量率范围不同， 仅根据所接受的总剂量来估计生物效应。 我们假设剂量率在放射治疗的结果中起着重要作用，可以 用于特定的治疗场景。对于极端情况，例如 FLASH 治疗，平均剂量 速率没有充分捕捉相关的时间结构。我们将应用蒙特卡罗模拟 确定从分钟临床尺度（点扫描/龙门旋转时间）到na-的时间结构 秒（点内传送时间）并评估对健康组织保护的潜在影响，这将影响 证明放射治疗患者的生活质量。

项目成果

Treatment planning considerations for the development of FLASH proton therapy.

• DOI: 10.1016/j.radonc.2022.08.003
• 发表时间: 2022-10
• 期刊: Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology
• 作者: Rothwell B;Lowe M;Traneus E;Krieger M;Schuemann J
• 通讯作者: Schuemann J

Modeling the impact of tissue oxygen profiles and oxygen depletion parameter uncertainties on biological response and therapeutic benefit of FLASH.

• DOI: 10.1002/mp.16366
• 发表时间: 2023-03
• 期刊: Medical physics
• 影响因子: 3.8
• 作者: Hongyu Zhu;J. Schuemann;Qixian Zhang;L. Gerweck