Journal article
Improving Head and Neck Cancer Treatments Using Dynamic Collimation in Spot Scanning Proton Therapy
International journal of particle therapy, Vol.2(4), pp.544-554
03/2016
DOI: 10.14338/IJPT-15-00026.1
PMCID: PMC6871640
PMID: 31772966
Abstract
Purpose: Interest in using collimation for spot scanning proton therapy has recently increased in an attempt to improve the lateral penumbra. To investigate the advantages of such an approach for complex targets, a plan comparison between uncollimated and collimated beam spots was performed for patients with head and neck cancer.
Patients and Methods: For 10 patients with head and neck cancer, previously treated with spot scanning proton therapy, uncollimated and collimated treatment plans were created using an in-house treatment-planning system capable of modeling asymmetric-beamlet dose distributions resulting from the use of a dynamic collimation system. Both uncollimated and collimated plans reproduced clinically delivered plans in terms of target coverage. A relative plan comparison was performed using both physical and radiobiological metrics on the organs at risk.
Results: The dynamic collimation system improved dose-distribution conformity while preserving target coverage. The median reduction of the mean dose to the esophagus, uninvolved larynx, and uninvolved parotids were −11.9% (minimum to maximum, −6.4% to −24.1%), −7.2% (−0.8% to −60.1%), and −5.2% (−0.2% to −21.5%), respectively, and depended on the organ location relative to the target and radiation beam angle. The collimation did not improve dose to some organs at risk surrounded by the target or located upstream of Bragg peaks because of the priority on the target coverage.
Conclusion: In spot scanning proton therapy, the dynamic collimation system generally affords better target conformity, which results in improvement in organ-at-risk sparing in the head and neck region while preserving target coverage. However, the benefits of collimation and the increased complexity should be considered for each patient. Patients with large bilateral targets or organs at risk surrounded by the target showed the least benefit.
Details
- Title: Subtitle
- Improving Head and Neck Cancer Treatments Using Dynamic Collimation in Spot Scanning Proton Therapy
- Creators
- Alexandra MoignierEdgar GeloverDongxu WangBlake SmithRyan FlynnMaura KirkLiyong LinTimothy SolbergAlexander LinDaniel Hyer
- Resource Type
- Journal article
- Publication Details
- International journal of particle therapy, Vol.2(4), pp.544-554
- Publisher
- The Particle Therapy Co-operative Group
- DOI
- 10.14338/IJPT-15-00026.1
- PMID
- 31772966
- PMCID
- PMC6871640
- ISSN
- 2331-5180
- eISSN
- 2331-5180
- Alternative title
- Head/neck cancer treatment with collimation in SSPT
- Language
- English
- Date published
- 03/2016
- Academic Unit
- Roy J. Carver Department of Biomedical Engineering; Radiation Oncology
- Record Identifier
- 9984047882602771
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