TY - JOUR
T1 - Variations in linear energy transfer distributions within a European proton therapy planning comparison of paediatric posterior fossa tumours
AU - Lægdsmand, Peter
AU - Matysiak, Witold
AU - Muren, Ludvig P.
AU - Lassen-Ramshad, Yasmin
AU - Maduro, John H.
AU - Vestergaard, Anne
AU - Righetto, Roberto
AU - Pettersson, Erik
AU - Kristensen, Ingrid
AU - Dutheil, Pauline
AU - Demoor-Goldschmidt, Charlotte
AU - Charlwood, Frances
AU - Whitfield, Gillian
AU - Feijoo, Marta M.
AU - Vela, Anthony
AU - Missohou, Fernand
AU - Vennarini, Sabina
AU - Mirandola, Alfredo
AU - Orlandi, Ester
AU - Rombi, Barbara
AU - Goedgebeur, Anneleen
AU - Van Beek, Karen
AU - Bannink-Gawryszuk, Agata
AU - Campoo, Fernando C.
AU - Engellau, Jacob
AU - Toussaint, Laura
N1 - Publisher Copyright:
© 2024 The Author(s)
PY - 2024/10
Y1 - 2024/10
N2 - Background and Purpose: Radiotherapy for paediatric posterior fossa tumours may cause complications in the brainstem and upper spinal cord due to high doses. With proton therapy (PT) this risk may increase due to higher relative biological effectiveness (RBE) from elevated linear energy transfer (LET). This study assesses variations in LET in the brainstem and spinal cord in proton treatment plans from European centres. Materials and Methods: Ten European PT centres using spot-scanning PT planned two paediatric posterior fossa cases: One overlapping partly with the brainstem and upper spinal cord, prescribed 54 Gy(RBE), and the second wrapping around these organs, prescribed 59.4 Gy(RBE). Dose-averaged LET distributions were assessed in volumes of the brainstem and spinal cord irradiated to over 50 Gy(RBE = 1.1). The maximum hinge angle effect on near-maximum RBE-weighted doses using the Unkelbach RBE model was also investigated. Results: In the first case, the mean LET in brainstem volumes receiving more than 50 Gy(RBE = 1.1) ranged from 2.8 keV/µm to 3.6 keV/µm across centres (median: 3.3 keV/µm). In the second case, treatment plans showed a narrower range of mean LET in the brainstem, from 2.5 keV/µm to 2.8 keV/µm (median: 2.7 keV/µm). There was no statistically significant impact of the maximum hinge angle. Conclusions: LET distributions vary across centres due to different techniques but are also influenced significantly by factors like shape and position of the target volume.
AB - Background and Purpose: Radiotherapy for paediatric posterior fossa tumours may cause complications in the brainstem and upper spinal cord due to high doses. With proton therapy (PT) this risk may increase due to higher relative biological effectiveness (RBE) from elevated linear energy transfer (LET). This study assesses variations in LET in the brainstem and spinal cord in proton treatment plans from European centres. Materials and Methods: Ten European PT centres using spot-scanning PT planned two paediatric posterior fossa cases: One overlapping partly with the brainstem and upper spinal cord, prescribed 54 Gy(RBE), and the second wrapping around these organs, prescribed 59.4 Gy(RBE). Dose-averaged LET distributions were assessed in volumes of the brainstem and spinal cord irradiated to over 50 Gy(RBE = 1.1). The maximum hinge angle effect on near-maximum RBE-weighted doses using the Unkelbach RBE model was also investigated. Results: In the first case, the mean LET in brainstem volumes receiving more than 50 Gy(RBE = 1.1) ranged from 2.8 keV/µm to 3.6 keV/µm across centres (median: 3.3 keV/µm). In the second case, treatment plans showed a narrower range of mean LET in the brainstem, from 2.5 keV/µm to 2.8 keV/µm (median: 2.7 keV/µm). There was no statistically significant impact of the maximum hinge angle. Conclusions: LET distributions vary across centres due to different techniques but are also influenced significantly by factors like shape and position of the target volume.
KW - Brainstem
KW - Linear Energy Transfer
KW - Paediatric
KW - Posterior fossa tumours
KW - Proton therapy
KW - Relative Biological Effectiveness
KW - Spinal cord
UR - http://www.scopus.com/inward/record.url?scp=85209588343&partnerID=8YFLogxK
U2 - 10.1016/j.phro.2024.100675
DO - 10.1016/j.phro.2024.100675
M3 - Journal article
AN - SCOPUS:85209588343
SN - 2405-6316
VL - 32
JO - Physics and Imaging in Radiation Oncology
JF - Physics and Imaging in Radiation Oncology
M1 - 100675
ER -