Aims

With interest in normal tissue sparing and dose-escalated radiotherapy in the treatment of inoperable locally advanced non-small cell lung cancer, this study investigated the impact of motion-managed moderate deep inspiration breath hold (mDIBH) on normal tissue sparing and dose-escalation potential and compared this to planning with a four-dimensional motion-encompassing internal target volume or motion-compensating mid-ventilation approach.

Materials and methods

Twenty-one patients underwent four-dimensional and mDIBH planning computed tomography scans. Internal and mid-ventilation target volumes were generated on the four-dimensional scan, with mDIBH target volumes generated on the mDIBH scan. Isotoxic target dose-escalation guidelines were used to generate six plans per patient: three with a target dose cap and three without. Target dose-escalation potential, normal tissue complication probability and differences in pre-specified dose-volume metrics were evaluated for the three motion-management techniques.

Results

The mean total lung volume was significantly greater with mDIBH compared with four-dimensional scans. Lung dose (mean and V_{21 Gy}) and mean heart dose were significantly reduced with mDIBH in comparison with four-dimensional-based approaches, and this translated to a significant reduction in heart and lung normal tissue complication probability with mDIBH. In 20/21 patients, the trial target prescription dose cap of 79.2 Gy was achievable with all motion-management techniques.

Conclusion

mDIBH aids lung and heart dose sparing in isotoxic dose-escalated radiotherapy compared with four-dimensional planning techniques. Given concerns about lung and cardiac toxicity, particularly in an era of consolidation immunotherapy, reduced normal tissue doses may be advantageous for treatment tolerance and outcome.

中文翻译：

---

肺癌等毒剂量递增放疗与中度深吸气屏气、中间换气和内部目标容积技术的比较

目标

本研究关注正常组织保留和剂量递增放射治疗治疗不可手术的局部晚期非小细胞肺癌，调查了运动管理的中度深吸气屏气 (mDIBH) 对正常组织保留和剂量递增的影响潜力并将其与使用四维运动包含内部目标体积或运动补偿中间通气方法的计划进行比较。

材料和方法

21 名患者接受了四维和 mDIBH 计划计算机断层扫描。在四维扫描上生成内部和中间通气目标体积，在 mDIBH 扫描上生成 mDIBH 目标体积。使用等毒目标剂量递增指南为每位患者生成六个计划：三个有目标剂量上限，三个没有。对三种运动管理技术的目标剂量递增潜力、正常组织并发症概率和预先指定的剂量体积指标的差异进行了评估。

结果

与四维扫描相比，mDIBH 的平均总肺容积显着更大。与基于四维的方法相比，使用 mDIBH 的肺剂量（平均和 V _{21 Gy ）和平均心脏剂量显着降低，这转化为 mDIBH 的心脏和肺正常组织并发症概率显着降低。}在 20/21 名患者中，所有运动管理技术均可实现 79.2 Gy 的试验目标处方剂量上限。

结论

与四维计划技术相比，mDIBH 有助于在等毒剂量递增放射治疗中节省肺和心脏剂量。鉴于对肺和心脏毒性的担忧，特别是在巩固免疫治疗的时代，减少正常组织剂量可能有利于治疗耐受性和结果。