A treatment planning comparison of photon stereotactic ablative radiotherapy and proton beam therapy for the re-irradiation of pelvic cancer recurrence
Authors
Chuter, RobertGlassborow, E.
Speight, R.
Clarke, M.
Murray, L.
Radhakrishna, Ganesh
Lavin, Victoria
Aspin, L.
Aldred, M.
Gregory, S.
Richardson, J.
Handley, J.
Affiliation
Christie Medical Physics and Engineering, The Christie NHS Foundation Trust, Wilmslow Road, Manchester M20 4BX, UK. Division of Cancer Sciences, Faculty of Biology, Medicine and Heath, University of Manchester, Manchester Academic Health Science Centre, The Christie NHS Foundation Trust, Wilmslow Road, Manchester M20 4BX, UK. Leeds Cancer Centre, Leeds Teaching Hospitals NHS Trust, Leeds, UK. Leeds Institute of Medical Research, University of Leeds, Leeds, UK. Clinical Oncology, The Christie NHS Foundation Trust, Wilmslow Road, Manchester M20 4BX, UK.Issue Date
2022
Metadata
Show full item recordAbstract
Background Patients who experience a pelvic cancer recurrence in or near a region that received initial radiotherapy, typically have few options for treatment. Organs at risk (OAR) have often reached their dose constraint limits leaving minimal dose remaining for standard re-irradiation (reRT). However, photon based stereotactic ablative radiotherapy (SABR) has been utilised for reRT with promising initial results although meeting OAR constraints can be challenging. Proton beam therapy (PBT) could offer an advantage. Materials and methods SABR plans used for treatment for ten pelvic reRT patients were dosimetrically compared to PBT plans retrospectively planned using the same CT and contour data. PBT plans were created to match the CTV dose coverage of SABR treatment plans with V100% ≥95%. An ‘as low as reasonably achievable’ approach was taken to OAR tolerances with consideration of OAR dose from the initial radiation (using equivalent dose in 2 Gy fractions). Results Dosimetric comparison of relevant OAR statistics showed a decrease in OAR dose using PBT over SABR in all patients, with equivalent target coverage. The largest statistically significant reduction was seen for the colon D0.5 cm3 with a median reduction from 13.1 Gy to 5.9 Gy. There were statistically significant dose reductions in the median dose to small bowel, sacral plexus and cauda equina. Conclusion PBT has the potential for significant dose reductions for OARs in the pelvic reRT setting compared to SABR. However, it remains unclear if the magnitude of these OAR dose reductions will translate into clinical benefit.Citation
Chuter R, Glassborow E, Speight R, Clarke M, Murray L, Radhakrishna G, et al. A treatment planning comparison of photon stereotactic ablative radiotherapy and proton beam therapy for the re-irradiation of pelvic cancer recurrence [Internet]. Vol. 21, Physics and Imaging in Radiation Oncology. Elsevier BV; 2022. p. 78–83.Journal
Physics and Imaging in Radiation OncologyDOI
10.1016/j.phro.2022.02.010PubMed ID
35243036Additional Links
https://dx.doi.org/10.1016/j.phro.2022.02.010Type
ArticleLanguage
enae974a485f413a2113503eed53cd6c53
10.1016/j.phro.2022.02.010