Dataset Information

Tissue-specific range uncertainty estimation in proton therapy.

ABSTRACT:

Background and purpose

Proton therapy is sensitive to range uncertainties, which typically are accounted for by margins or robust optimization, based on tissue-independent uncertainties. However, range uncertainties have been shown to depend on the specific tissues traversed. The aim of this study was to investigate the differences between range margins based on stopping power ratio (SPR) uncertainties which were tissue-specific (applied voxel-wise) or fixed (tissue-independent or composite).

Materials and methods

Uncertainties originating from imaging, computed tomography (CT) number estimation, and SPR estimation were calculated for low-, medium-, and high-density tissues to quantify the tissue-specific SPR uncertainties. Four clinical treatment plans (four different tumor sites) were created and recomputed after applying either tissue-specific or fixed SPR uncertainties. Plans with tissue-specific and fixed uncertainties were compared, based on dose-volume-histogram parameters for both targets and organs-at-risk.

Results

The total SPR uncertainties were 7.0% for low-, 1.0% for medium-, and 1.3% for high-density tissues. Differences between the proton plans with tissue-specific and fixed uncertainties were mainly found in the vicinity of the target. Composite uncertainties were found to capture the tissue-specific uncertainties more accurately than the tissue-independent uncertainties.

Conclusion

Different SPR uncertainties were found for low-, medium-, and high-density tissues indicating that range margins based on tissue-specific uncertainties may be more exact than the standard approach of using tissue-independent uncertainties. Differences between applying tissue-specific and fixed uncertainties were found, however, a fixed uncertainty might still be sufficient, but with a magnitude that depends on the body region.

SUBMITTER: Vestergaard CD

PROVIDER: S-EPMC10173296 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature

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Publications

Tissue-specific range uncertainty estimation in proton therapy.

Vestergaard Casper Dueholm CD Muren Ludvig Paul LP Elstrøm Ulrik Vindelev UV Johansen Jacob Graversen JG Taasti Vicki Trier VT

Physics and imaging in radiation oncology 20230422

<h4>Background and purpose</h4>Proton therapy is sensitive to range uncertainties, which typically are accounted for by margins or robust optimization, based on tissue-independent uncertainties. However, range uncertainties have been shown to depend on the specific tissues traversed. The aim of this study was to investigate the differences between range margins based on stopping power ratio (SPR) uncertainties which were tissue-specific (applied voxel-wise) or fixed (tissue-independent or compos ...[more]

PMID: 37182194

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Dataset Information

Tissue-specific range uncertainty estimation in proton therapy.

Background and purpose

Materials and methods

Results

Conclusion

Publications

Tissue-specific range uncertainty estimation in proton therapy.

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