Dosimetric benefits of daily treatment plan adaptation for prostate cancer stereotactic body radiotherapy

• Verfasst von: Eckl, Miriam [VerfasserIn]
• Verfasst von: Sarria, Gustavo R. [VerfasserIn]
• Verfasst von: Springer, Sandra A. [VerfasserIn]
• Verfasst von: Willam, Marvin [VerfasserIn]
• Verfasst von: Ruder, Arne Mathias [VerfasserIn]
• Verfasst von: Steil, Volker [VerfasserIn]
• Verfasst von: Ehmann, Michael [VerfasserIn]
• Verfasst von: Wenz, Frederik [VerfasserIn]
• Verfasst von: Fleckenstein, Jens [VerfasserIn]
• Titel: Dosimetric benefits of daily treatment plan adaptation for prostate cancer stereotactic body radiotherapy
• Verf.angabe: Miriam Eckl, Gustavo R. Sarria, Sandra Springer, Marvin Willam, Arne M. Ruder, Volker Steil, Michael Ehmann, Frederik Wenz and Jens Fleckenstein
• E-Jahr: 2021
• Jahr: 04 August 2021
• Umfang: 13 S.
• Fussnoten: Gesehen am 03.05.2023
• Titel Quelle: Enthalten in: Radiation oncology
• Ort Quelle: London : BioMed Central, 2006
• Jahr Quelle: 2021
• Band/Heft Quelle: 16(2021), Artikel-ID 145, Seite 1-13
• ISSN Quelle: 1748-717X
• DOI: doi:10.1186/s13014-021-01872-9
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1844491765
• K10plus-PPN:
  Universitätsbibliothek
• Lokale URL UB: Zum Volltext

Abstract

Background:  Hypofractionation is increasingly being applied in radiotherapy for prostate cancer, requiring higher accuracy of daily treatment deliveries than in conventional image-guided radiotherapy (IGRT). Different adaptive radiotherapy (ART) strategies were evaluated with regard to dosimetric benefits. - Methods:  Treatments plans for 32 patients were retrospectively generated and analyzed according to the PACE-C trial treatment scheme (40 Gy in 5 fractions). Using a previously trained cycle-generative adversarial network algorithm, synthetic CT (sCT) were generated out of five daily cone-beam CT. Dose calculation on sCT was performed for four different adaptation approaches: IGRT without adaptation, adaptation via segment aperture morphing (SAM) and segment weight optimization (ART1) or additional shape optimization (ART2) as well as a full re-optimization (ART3). Dose distributions were evaluated regarding dose-volume parameters and a penalty score. - Results:  Compared to the IGRT approach, the ART1, ART2 and ART3 approaches substantially reduced the ­V37Gy(bladder) and ­V36Gy(rectum) from a mean of 7.4cm3 and 2.0cm3 to (5.9cm3, 6.1cm3, 5.2cm3) as well as to (1.4cm3, 1.4cm3, 1.0cm3), respectively. Plan adaptation required on average 2.6 min for the ART1 approach and yielded doses to the rectum being insignificantly different from the ART2 approach. Based on an accumulation over the total patient collective, a penalty score revealed dosimetric violations reduced by 79.2%, 75.7% and 93.2% through adaptation. - Conclusion:  Treatment plan adaptation was demonstrated to adequately restore relevant dose criteria on a daily basis. While for SAM adaptation approaches dosimetric benefits were realized through ensuring sufficient target coverage, a full re-optimization mainly improved OAR sparing which helps to guide the decision of when to apply which adaptation strategy.