基于蒙特卡洛的扫描质子束用于乳腺癌的投入使用:结合LETd计算和可变RBE模型
Zhen Cao1,2, Qing Zhang3, Jingfang Zhao1
1Department of Medical Physics, Shanghai Proton and Heavy Ion Center, Fudan University Cancer Hospital, Shanghai Key Laboratory of Radiation Oncology, Shanghai Engineering Research Center of Proton and Heavy Ion Radiation Therapy, Shanghai, People's Republic of China.
Journal of applied clinical medical physics
|January 27, 2026
概括
一个新的蒙特卡洛模型准确计算了质子治疗中的可变相对生物有效性 (RBE),提高了乳腺癌患者的剂量准确性,并可能减少肋骨骨折等副作用.
科学领域:
- 医学物理 医学物理
- 辐射瘤学 辐射瘤学
- 计算生物学 计算生物学
背景情况:
- 质子疗法的恒定相对生物有效性 (RBE) 假设可能导致高能量区域的剂量低估.
- 这种不准确性限制了对质子疗法临床结果的准确预测.
- 精确的RBE加权剂量计算对于优化治疗和最大限度地减少毒性至关重要.
研究的目的:
- 开发和验证乳腺癌质子治疗的蒙特卡洛 (MC) 模型.
- 该模型包含可变RBE,以增强RBE加权剂量计算.
- 旨在提高治疗准确性,更可靠地预测临床结果.
主要方法:
- 一个基于FLUKA的质子束线的MC模型被委托并根据治疗计划系统 (TPS) 和物理测量进行验证.
- 使用麦克马洪,麦克纳马拉和韦登伯格模型计算了可变的RBE加权剂量分布.
- 用DVH,马分析和LETd体积直方图分析了四例乳腺癌病例,以比较TPS和MC结果.
主要成果:
- 该MC模型与TPS和测量结果有很好的一致性 (质子范围偏差<0.1毫米).
- 与没有骨折的患者相比,在骨折患者的肋骨区域观察到较高的RBE权重剂量.
- 可变的RBE模型预测了远距离光束区域中较高的RBE加权剂量,以及肺炎患者的肺V20升高.
结论:
- 经过验证的MC框架成功地整合了多变量RBE模型,用于质子疗法中剂量估计.
- 这种方法显示出更准确的RBE加权剂量计算的希望.
- 可行整合可变RBE模型提高了质子疗法规划的精度.
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