A Comparison of Isotoxic Dose-escalated Radiotherapy in Lung Cancer with Moderate Deep Inspiration Breath Hold, Mid-ventilation and Internal Target Volume Techniques. Issue 3 (March 2022)

• Record Type: Journal Article
• Authors: Bainbridge, H.; Dunlop, A.; McQuaid, D.; Gulliford, S.; Gunapala, R.; Ahmed, M.; Locke, I.; Nill, S.; Oelfke, U.; McDonald, F.
• Is Part Of: Clinical oncology. Volume 34:Issue 3(2022)
• Page Start: 151
• Page End: 159
• Publication Date: 2022-03
• Subjects: Breath hold -- lung radiotherapy -- normal tissue; Oncology -- Periodicals; Tumors -- Periodicals; Cancer -- Treatment -- Periodicals; Radiotherapy -- Periodicals; Neoplasms -- Periodicals; Cancer -- Radiotherapy; Cancer -- Treatment; Oncology; Medical radiology; Radiotherapy; Tumors; Electronic journals; Periodicals; 616.994
• DOI: 10.1016/j.clon.2021.08.012
• Languages: English
• ISSNs: 0936-6555

Abstract

Abstract: 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 V21 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. Highlights: mDIBH significantly increases lung volumes compared with 4DCT for lung radiotherapy. Heart and lung dose is significantly lower with mDIBH compared with 4DCT techniques. More than 20% reduction in modelled pneumonitis risk is seen with mDIBH versus 4DCT. mDIBH may be particularly beneficial in patients receiving adjuvant immunotherapy. mDIBH warrants further assessment, ideally within a randomised clinical trial.