文章：

磁共振引导放射治疗在前列腺癌与胰腺癌治疗中的应用：两大磁共振直线加速器平台的剂量学研究

MR-Guided Radiation Therapy for Prostate and Pancreas Cancer Treatment: A Dosimetric Study Across Two Major MR-Linac Platforms

原文发布日期：20 August 2025

DOI: 10.3390/cancers17162708

类型: Article

开放获取: 是

英文摘要：

Background/Objectives:MR-guided radiation therapy (MRgRT) has rapidly evolved into an important treatment modality, with the Elekta Unity and ViewRay MRIdian systems being two major MR-linac platforms. Despite the shared concept of MRgRT, the two platforms elected different system designs that could potentially impact the dosimetric characteristics and quality of a treatment. In this study, we aim to perform a comparative dosimetric investigation between these two MR-linac systems in prostate and pancreas cancers.Methods: Dosimetric characteristics were evaluated by retrospectively re-creating 20 clinical prostate and pancreas cases originally treated on MRIdian using the Unity system, adhering to MIRAGE and SMART clinical trial constraints. Treatment plans were re-created with matching planning images, structures, beam geometry, and dose parameters. To ensure comparison consistency, all Unity treatment plans were normalized to match the target coverage of the MRIdian counterparts, and the organ-at-risk (OAR) dose was investigated.Results: Most OARs’ dose-volume metrics showed no statistically significant differences. For prostate patients, Unity demonstrated lower rectum V36Gy (p= 0.0095), V38Gy (p= 0.0043), V40Gy (p= 0.0469), and lower left (p= 0.0137) and right femur V20Gy (p= 0.0020). For pancreas patients, Unity plans had a lower mean liver dose (p= 0.0371). All Unity plans had a Gamma passing rate > 90%, confirming the clinical deliverability. Mean delivery times were 12.78 ± 1.68 and 13.53 ± 1.88 min for MRIdian and Unity prostate plans, respectively, and 14.58 ± 2.78 and 17.40 ± 3.77 min for MRIdian and Unity pancreas plans, respectively.Conclusions: Overall, comparable treatment quality and delivery times were observed between the two platforms.

摘要翻译： 

背景/目的：磁共振引导放射治疗（MRgRT）已迅速发展为一种重要的治疗方式，其中Elekta Unity和ViewRay MRIdian系统是两大主流磁共振直线加速器平台。尽管两者共享MRgRT的基本理念，但其系统设计存在差异，可能对治疗的剂量学特性与质量产生影响。本研究旨在对这两种磁共振直线加速器系统在前列腺癌和胰腺癌治疗中的剂量学表现进行对比分析。 方法：通过回顾性研究，将原本在MRIdian系统上治疗的20例前列腺和胰腺临床病例，在Unity系统上按照MIRAGE和SMART临床试验的限制条件重新制定治疗计划。计划重建过程中保持了影像数据、结构勾画、射束几何参数及剂量参数的一致性。为确保对比的公平性，所有Unity治疗计划均经过归一化处理，使其靶区覆盖度与对应的MRIdian计划相匹配，并重点分析危及器官的受照剂量。 结果：多数危及器官的剂量-体积指标未显示统计学显著差异。对于前列腺癌患者，Unity系统在直肠V36Gy（p=0.0095）、V38Gy（p=0.0043）、V40Gy（p=0.0469）以及左股骨V20Gy（p=0.0137）和右股骨V20Gy（p=0.0020）方面表现出更优的剂量控制。对于胰腺癌患者，Unity计划的平均肝脏剂量更低（p=0.0371）。所有Unity计划的Gamma通过率均>90%，证实了其临床可实施性。MRIdian与Unity的前列腺计划平均照射时间分别为12.78±1.68分钟和13.53±1.88分钟；胰腺计划平均照射时间分别为14.58±2.78分钟和17.40±3.77分钟。 结论：总体而言，两种平台在治疗质量和照射时间方面表现出可比性。

原文链接：

MR-Guided Radiation Therapy for Prostate and Pancreas Cancer Treatment: A Dosimetric Study Across Two Major MR-Linac Platforms