A Comparison of Isotoxic Dose-escalated Radiotherapy in Lung Cancer with Moderate Deep Inspiration Breath Hold, Mid-ventilation and Internal Target Volume Techniques

H Bainbridge; A Dunlop; D McQuaid; S Gulliford; R Gunapala; M Ahmed; I Locke; S Nill; U Oelfke; F McDonald

doi:10.1016/j.clon.2021.08.012

A Comparison of Isotoxic Dose-escalated Radiotherapy in Lung Cancer with Moderate Deep Inspiration Breath Hold, Mid-ventilation and Internal Target Volume Techniques

Clin Oncol (R Coll Radiol). 2022 Mar;34(3):151-159. doi: 10.1016/j.clon.2021.08.012. Epub 2021 Sep 7.

Authors

H Bainbridge¹, A Dunlop², D McQuaid², S Gulliford², R Gunapala³, M Ahmed¹, I Locke⁴, S Nill², U Oelfke², F McDonald⁵

Affiliations

¹ Department of Radiotherapy at The Royal Marsden NHS Foundation Trust, Sutton, UK; The Institute of Cancer Research, London, UK.
² Joint Department of Physics at The Royal Marsden NHS Foundation Trust and The Institute of Cancer Research, London, UK.
³ Department of Statistics at The Royal Marsden NHS Foundation Trust, Sutton, UK.
⁴ Department of Radiotherapy at The Royal Marsden NHS Foundation Trust, Sutton, UK.
⁵ Department of Radiotherapy at The Royal Marsden NHS Foundation Trust, Sutton, UK; The Institute of Cancer Research, London, UK. Electronic address: fiona.mcdonald@rmh.nhs.uk.

PMID: 34503896
DOI: 10.1016/j.clon.2021.08.012

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 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.

Keywords: Breath hold; lung radiotherapy; normal tissue.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Breath Holding
Carcinoma, Non-Small-Cell Lung* / radiotherapy
Humans
Lung
Lung Neoplasms* / radiotherapy
Radiotherapy Dosage
Radiotherapy Planning, Computer-Assisted / methods

Abstract

Publication types

MeSH terms

Grants and funding