Dataset Information

Positron emission tomography guided dose painting by numbers of lung cancer: Alanine dosimetry in an anthropomorphic phantom.

ABSTRACT:

Background and purpose

Dose painting by numbers (DPBN) require a high degree of dose modulation to fulfill the image-based voxel wise dose prescription. The aim of this study was to assess the dosimetric accuracy of ¹⁸F-fluoro-2-deoxy-glucose positron emission tomography(¹⁸F-FDG-PET)-based DPBN in an anthropomorphic lung phantom using alanine dosimetry.

Materials and methods

A linear dose prescription based on ¹⁸F-FDG-PET image intensities within the gross tumor volume (GTV) of a lung cancer patient was employed. One DPBN scheme with low dose modulation (Scheme A; minimum/maximum fraction dose to the GTV 2.92/4.26 Gy) and one with a high modulation (Scheme B; 2.81/4.52 Gy) were generated. The plans were transferred to a computed tomograpy (CT) scan of a thorax phantom based on CT images of the patient. Using volumetric modulated arc therapy (VMAT), DPBN was delivered to the phantom with embedded alanine dosimeters. A plan was also delivered to an intentionally misaligned phantom. Absorbed doses at various points in the phantom were measured by alanine dosimetry.

Results

A pointwise comparison between GTV doses from prescription, treatment plan calculation and VMAT delivery showed high correspondence, with a mean and maximum dose difference of <0.1 Gy and 0.3 Gy, respectively. No difference was found in dosimetric accuracy between scheme A and B. The misalignment caused deviations up to 1 Gy between prescription and delivery.

Conclusion

DPBN can be delivered with high accuracy, showing that the treatment may be applied correctly from a dosimetric perspective. Still, misalignment may cause considerable dosimetric erros, indicating the need for patient immobilization and monitoring.

SUBMITTER: Papoutsis I

PROVIDER: S-EPMC8885607 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Publications

Positron emission tomography guided dose painting by numbers of lung cancer: Alanine dosimetry in an anthropomorphic phantom.

Papoutsis Iosif I Skjei Knudtsen Ingerid I Peter Skaug Sande Erlend E Louni Rekstad Bernt B Öllers Michel M van Elmpt Wouter W Røthe Arnesen Marius M Malinen Eirik E

Physics and imaging in radiation oncology 20220101

<h4>Background and purpose</h4>Dose painting by numbers (DPBN) require a high degree of dose modulation to fulfill the image-based voxel wise dose prescription. The aim of this study was to assess the dosimetric accuracy of <sup>18</sup>F-fluoro-2-deoxy-glucose positron emission tomography(<sup>18</sup>F-FDG-PET)-based DPBN in an anthropomorphic lung phantom using alanine dosimetry.<h4>Materials and methods</h4>A linear dose prescription based on <sup>18</sup>F-FDG-PET image intensities within t ...[more]

PMID: 35243040

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Dataset Information

Positron emission tomography guided dose painting by numbers of lung cancer: Alanine dosimetry in an anthropomorphic phantom.

Background and purpose

Materials and methods

Results

Conclusion

Publications

Positron emission tomography guided dose painting by numbers of lung cancer: Alanine dosimetry in an anthropomorphic phantom.

Similar Datasets

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