Feasibility and constraints of Bragg peak FLASH proton therapy treatment planning
(2024) In Frontiers in Oncology 14.- Abstract
Introduction: FLASH proton therapy (FLASH-PT) requires ultra-high dose rate (≥ 40 Gy/s) protons to be delivered in a short timescale whilst conforming to a patient-specific target. This study investigates the feasibility and constraints of Bragg peak FLASH-PT treatment planning, and compares the in silico results produced to plans for intensity modulated proton therapy (IMPT). Materials and method: Bragg peak FLASH-PT and IMPT treatment plans were generated for bone (n=3), brain (n=3), and lung (n=4) targets using the MIROpt research treatment planning system and the Conformal FLASH library developed by Applications SA from the open-source version of UCLouvain. FLASH-PT beams were simulated using monoenergetic spot-scanned protons... (More)
Introduction: FLASH proton therapy (FLASH-PT) requires ultra-high dose rate (≥ 40 Gy/s) protons to be delivered in a short timescale whilst conforming to a patient-specific target. This study investigates the feasibility and constraints of Bragg peak FLASH-PT treatment planning, and compares the in silico results produced to plans for intensity modulated proton therapy (IMPT). Materials and method: Bragg peak FLASH-PT and IMPT treatment plans were generated for bone (n=3), brain (n=3), and lung (n=4) targets using the MIROpt research treatment planning system and the Conformal FLASH library developed by Applications SA from the open-source version of UCLouvain. FLASH-PT beams were simulated using monoenergetic spot-scanned protons traversing through a conformal energy modulator, a range shifter, and an aperture. A dose rate constraint of ≥ 40 Gy/s was included in each FLASH-PT plan optimisation. Results: Space limitations in the FLASH-PT adapted beam nozzle imposed a maximum target width constraint, excluding 4 cases from the study. FLASH-PT plans did not satisfy the imposed target dose constraints (D95% ≥ 95% and D2%≤ 105%) but achieved clinically acceptable doses to organs at risk (OARs). IMPT plans adhered to all target and OAR dose constraints. FLASH-PT plans showed a reduction in both target homogeneity (p < 0.001) and dose conformity (non-significant) compared to IMPT. Conclusion: Without accounting for a sparing effect, IMPT plans were superior in target coverage, dose conformity, target homogeneity, and OAR sparing compared to FLASH-PT. Further research is warranted in treatment planning optimisation and beam delivery for clinical implementation of Bragg peak FLASH-PT.
(Less)
- author
- Lövgren, Nathalie ; Fagerström Kristensen, Ingrid LU and Petersson, Kristoffer LU
- organization
- publishing date
- 2024
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Bragg peak, feasibility studies, FLASH radiotherapy, intensity-modulated proton therapy, proton therapy
- in
- Frontiers in Oncology
- volume
- 14
- article number
- 1369065
- publisher
- Frontiers Media S. A.
- external identifiers
-
- scopus:85192520694
- pmid:38737902
- ISSN
- 2234-943X
- DOI
- 10.3389/fonc.2024.1369065
- language
- English
- LU publication?
- yes
- id
- 06961816-e2ad-432a-98fa-3cdec09d364e
- date added to LUP
- 2024-06-10 12:50:01
- date last changed
- 2024-09-16 22:07:02
@article{06961816-e2ad-432a-98fa-3cdec09d364e, abstract = {{<p>Introduction: FLASH proton therapy (FLASH-PT) requires ultra-high dose rate (≥ 40 Gy/s) protons to be delivered in a short timescale whilst conforming to a patient-specific target. This study investigates the feasibility and constraints of Bragg peak FLASH-PT treatment planning, and compares the in silico results produced to plans for intensity modulated proton therapy (IMPT). Materials and method: Bragg peak FLASH-PT and IMPT treatment plans were generated for bone (n=3), brain (n=3), and lung (n=4) targets using the MIROpt research treatment planning system and the Conformal FLASH library developed by Applications SA from the open-source version of UCLouvain. FLASH-PT beams were simulated using monoenergetic spot-scanned protons traversing through a conformal energy modulator, a range shifter, and an aperture. A dose rate constraint of ≥ 40 Gy/s was included in each FLASH-PT plan optimisation. Results: Space limitations in the FLASH-PT adapted beam nozzle imposed a maximum target width constraint, excluding 4 cases from the study. FLASH-PT plans did not satisfy the imposed target dose constraints (D<sub>95%</sub> ≥ 95% and D<sub>2%</sub>≤ 105%) but achieved clinically acceptable doses to organs at risk (OARs). IMPT plans adhered to all target and OAR dose constraints. FLASH-PT plans showed a reduction in both target homogeneity (p < 0.001) and dose conformity (non-significant) compared to IMPT. Conclusion: Without accounting for a sparing effect, IMPT plans were superior in target coverage, dose conformity, target homogeneity, and OAR sparing compared to FLASH-PT. Further research is warranted in treatment planning optimisation and beam delivery for clinical implementation of Bragg peak FLASH-PT.</p>}}, author = {{Lövgren, Nathalie and Fagerström Kristensen, Ingrid and Petersson, Kristoffer}}, issn = {{2234-943X}}, keywords = {{Bragg peak; feasibility studies; FLASH radiotherapy; intensity-modulated proton therapy; proton therapy}}, language = {{eng}}, publisher = {{Frontiers Media S. A.}}, series = {{Frontiers in Oncology}}, title = {{Feasibility and constraints of Bragg peak FLASH proton therapy treatment planning}}, url = {{http://dx.doi.org/10.3389/fonc.2024.1369065}}, doi = {{10.3389/fonc.2024.1369065}}, volume = {{14}}, year = {{2024}}, }