PMID- 37090848
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20230425
IS  - 2405-6308 (Electronic)
IS  - 2405-6308 (Linking)
VI  - 40
DP  - 2023 May
TI  - Effect of 0.35 T and 1.5 T magnetic fields on superficial dose in MR-guided 
      radiotherapy of laryngeal cancer.
PG  - 100624
LID - 10.1016/j.ctro.2023.100624 [doi]
LID - 100624
AB  - BACKGROUND: Treatment of head and neck cancer on linear accelerators with 
      on-board magnetic resonance imaging (MR-linac) might be beneficial to reduce side 
      effects and increase accuracy. For many head and neck cancer patients, dose 
      coverage of the often superficially located planning target volumes (PTVs) is 
      required. This study examines the impact of the electron return effect (ERE) on 
      the surface dose in MR-guided radiotherapy (MRgRT) compared to conventional 
      radiotherapy. MATERIALS AND METHODS: For this bicentric dosimetric study, 14 
      cases of laryngeal carcinomas with PTVs reaching up to the skin surface were 
      included. For each patient, five different plans were compared, two VMAT plans 
      (with and without a 5 mm bolus) and three IMRT MRgRT plans (0.35 T, 1.5 T and 
      0 T, each without bolus). Dose distributions were also validated with film 
      measurements. RESULTS: A similar coverage on the most superficial 3-5 mm of the 
      PTV was achieved in the VMAT plans with bolus and the MRgRT plans for both 0.35 T 
      and 1.5 T. However, coverage on this region was usually not achieved for VMAT 
      without bolus and the 0 T plans. The film measurements on phantoms confirmed the 
      results with the relative error never exceeding the calculated differences 
      between the plans. CONCLUSION: The present study could demonstrate that the ERE 
      for both commercially available MR-linac variants provides sufficient coverage of 
      the superficial tissue layers in MRgRT-plans for laryngeal carcinoma.
CI  - (c) 2023 The Author(s).
FAU - Conrad, Mireille
AU  - Conrad M
AD  - Institute of Radiation Physics, Lausanne University Hospital, Rue du Grand-Pre 
      1., 1007 Lausanne, Switzerland.
AD  - Department of Radiation Oncology, University of Zurich, Ramistrasse 100, 8091 
      Zurich, Switzerland.
FAU - Dal Bello, Riccardo
AU  - Dal Bello R
AD  - Department of Radiation Oncology, University of Zurich, Ramistrasse 100, 8091 
      Zurich, Switzerland.
FAU - van Timmeren, Janita E
AU  - van Timmeren JE
AD  - Department of Radiation Oncology, Radboud University Medical Centre, Geert 
      Grooteplein Zuid 32, 6525GA Nijmegen, The Netherlands.
FAU - Andratschke, Nicolaus
AU  - Andratschke N
AD  - Department of Radiation Oncology, University of Zurich, Ramistrasse 100, 8091 
      Zurich, Switzerland.
FAU - Wilke, Lotte
AU  - Wilke L
AD  - Department of Radiation Oncology, University of Zurich, Ramistrasse 100, 8091 
      Zurich, Switzerland.
FAU - Guckenberger, Matthias
AU  - Guckenberger M
AD  - Department of Radiation Oncology, University of Zurich, Ramistrasse 100, 8091 
      Zurich, Switzerland.
FAU - Tanadini-Lang, Stephanie
AU  - Tanadini-Lang S
AD  - Department of Radiation Oncology, University of Zurich, Ramistrasse 100, 8091 
      Zurich, Switzerland.
FAU - Balermpas, Panagiotis
AU  - Balermpas P
AD  - Department of Radiation Oncology, University of Zurich, Ramistrasse 100, 8091 
      Zurich, Switzerland.
LA  - eng
PT  - Journal Article
DEP - 20230401
PL  - Ireland
TA  - Clin Transl Radiat Oncol
JT  - Clinical and translational radiation oncology
JID - 101713416
PMC - PMC10113768
OTO - NOTNLM
OT  - Electron return effect
OT  - Head and neck
OT  - MR-Linac
OT  - MR-guided radiotherapy
OT  - Radiotherapy
COIS- The authors declare that they have no known competing financial interests or 
      personal relationships that could have appeared to influence the work reported in 
      this paper.
EDAT- 2023/04/24 06:42
MHDA- 2023/04/24 06:43
PMCR- 2023/04/01
CRDT- 2023/04/24 03:47
PHST- 2023/03/29 00:00 [received]
PHST- 2023/03/30 00:00 [accepted]
PHST- 2023/04/24 06:43 [medline]
PHST- 2023/04/24 06:42 [pubmed]
PHST- 2023/04/24 03:47 [entrez]
PHST- 2023/04/01 00:00 [pmc-release]
AID - S2405-6308(23)00049-6 [pii]
AID - 100624 [pii]
AID - 10.1016/j.ctro.2023.100624 [doi]
PST - epublish
SO  - Clin Transl Radiat Oncol. 2023 Apr 1;40:100624. doi: 10.1016/j.ctro.2023.100624. 
      eCollection 2023 May.