eprintid: 10074652 rev_number: 16 eprint_status: archive userid: 608 dir: disk0/10/07/46/52 datestamp: 2019-05-23 11:29:27 lastmod: 2021-09-20 22:21:31 status_changed: 2019-05-23 11:29:27 type: article metadata_visibility: show creators_name: Ranger, A creators_name: Dunlop, A creators_name: Hutchinson, K creators_name: Convery, H creators_name: Maclennan, MK creators_name: Chantler, H creators_name: Twyman, N creators_name: Rose, C creators_name: McQuaid, D creators_name: Amos, RA creators_name: Griffin, C creators_name: deSouza, NM creators_name: Donovan, E creators_name: Harris, E creators_name: Coles, CE creators_name: Kirby, A title: A Dosimetric Comparison of Breast Radiotherapy Techniques to Treat Locoregional Lymph Nodes Including the Internal Mammary Chain ispublished: pub divisions: UCL divisions: B04 divisions: C05 divisions: F42 keywords: Heart-sparing radiotherapy; internal mammary chain radiotherapy; proton beam therapy for breast cancer note: Copyright 2018 Published by Elsevier Ltd on behalf of The Royal College of Radiologists. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). abstract: Aims Radiotherapy target volumes in early breast cancer treatment increasingly include the internal mammary chain (IMC). In order to maximise survival benefits of IMC radiotherapy, doses to the heart and lung should be minimised. This dosimetry study compared the ability of three-dimensional conformal radiotherapy, arc therapy and proton beam therapy (PBT) techniques with and without breath-hold to achieve target volume constraints while minimising dose to organs at risk (OARs). Materials and methods In 14 patients' datasets, seven IMC radiotherapy techniques were compared: wide tangent (WT) three-dimensional conformal radiotherapy, volumetric-modulated arc therapy (VMAT) and PBT, each in voluntary deep inspiratory breath-hold (vDIBH) and free breathing (FB), and tomotherapy in FB only. Target volume coverage and OAR doses were measured for each technique. These were compared using a one-way ANOVA with all pairwise comparisons tested using Bonferroni's multiple comparisons test, with adjusted P-values ≤ 0.05 indicating statistical significance. Results One hundred per cent of WT(vDIBH), 43% of WT(FB), 100% of VMAT(vDIBH), 86% of VMAT(FB), 100% of tomotherapy FB and 100% of PBT plans in vDIBH and FB passed all mandatory constraints. However, coverage of the IMC with 90% of the prescribed dose was significantly better than all other techniques using VMAT(vDIBH), PBT(vDIBH) and PBT(FB) (mean IMC coverage ± 1 standard deviation = 96.0% ± 4.3, 99.8% ± 0.3 and 99.0% ± 0.2, respectively). The mean heart dose was significantly reduced in vDIBH compared with FB for both the WT (P < 0.0001) and VMAT (P < 0.0001) techniques. There was no advantage in target volume coverage or OAR doses for PBT(vDIBH) compared with PBT(FB). Conclusions Simple WT radiotherapy delivered in vDIBH achieves satisfactory coverage of the IMC while meeting heart and lung dose constraints. However, where higher isodose coverage is required, VMAT(vDIBH) is the optimal photon technique. The lowest OAR doses are achieved by PBT, in which the use of vDIBH does not improve dose statistics. date: 2018-06 date_type: published publisher: ELSEVIER SCIENCE LONDON official_url: https://doi.org/10.1016/j.clon.2018.01.017 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 1562749 doi: 10.1016/j.clon.2018.01.017 lyricists_name: Amos, Richard lyricists_id: RAMOS45 actors_name: Kalinowski, Damian actors_id: DKALI47 actors_role: owner full_text_status: public publication: Clinical Oncology volume: 30 number: 6 pagerange: 346-353 pages: 8 issn: 1433-2981 citation: Ranger, A; Dunlop, A; Hutchinson, K; Convery, H; Maclennan, MK; Chantler, H; Twyman, N; ... Kirby, A; + view all <#> Ranger, A; Dunlop, A; Hutchinson, K; Convery, H; Maclennan, MK; Chantler, H; Twyman, N; Rose, C; McQuaid, D; Amos, RA; Griffin, C; deSouza, NM; Donovan, E; Harris, E; Coles, CE; Kirby, A; - view fewer <#> (2018) A Dosimetric Comparison of Breast Radiotherapy Techniques to Treat Locoregional Lymph Nodes Including the Internal Mammary Chain. Clinical Oncology , 30 (6) pp. 346-353. 10.1016/j.clon.2018.01.017 <https://doi.org/10.1016/j.clon.2018.01.017>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10074652/1/Amos_A%20Dosimetric%20Comparison%20of%20Breast%20Radiotherapy%20Techniques%20to%20Treat%20Locoregional%20Lymph%20Nodes%20Including%20the%20Internal%20Mammary%20Chain_VoR.pdf