title: Benefit of particle therapy in re-irradiation of head and neck patients. Results of a multicentric in silico ROCOCO trial.
abstract: In this multicentric in silico trial we compared photon, proton, and carbon-ion radiotherapy plans for re-irradiation of patients with squamous cell carcinoma of the head and neck (HNSCC) regarding dose to tumour and doses to surrounding organs at risk (OARs).
  
  
  
  Twenty-five HNSCC patients with a second new or recurrent cancer after previous irradiation (70Gy) were included. Intensity-modulated proton therapy (IMPT) and ion therapy (IMIT) re-irradiation plans to a second subsequent dose of 70Gy were compared to photon therapy delivered with volumetric modulated arc therapy (VMAT).
  
  
  
  When comparing IMIT and IMPT to VMAT, the mean dose to all investigated 22 OARs was significantly reduced for IMIT and to 15 out of 22 OARs (68%) using IMPT. The maximum dose to 2% volume (D2) of the brainstem and spinal cord were significantly reduced using IMPT and IMIT compared to VMAT. The data are available on www.cancerdata.org.
  
  
  
  In this ROCOCO in silico trial, a reduction in mean dose to OARs was achieved using particle therapy compared to photons in the re-irradiation of HNSCC. There was a dosimetric benefit favouring carbon-ions above proton therapy. These dose reductions may potentially translate into lower severe complication rates related to the re-irradiation.
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, The Netherlands. Electronic address: danielle.eekers@maastro.nl.
authors.forename: Daniëlle B P
authors.initials: DBP
authors.lastname: Eekers
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, The Netherlands.
authors.forename: Erik
authors.initials: E
authors.lastname: Roelofs
authors.affiliation: Department of Radiotherapy and Radiation Oncology, University of Marburg, Germany.
authors.forename: Urszula
authors.initials: U
authors.lastname: Jelen
authors.affiliation: Hospital of the University of Pennsylvania (UPenn), USA.
authors.forename: Maura
authors.initials: M
authors.lastname: Kirk
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, The Netherlands.
authors.forename: Marlies
authors.initials: M
authors.lastname: Granzier
authors.affiliation: Department of Radiotherapy and Radiation Oncology, University of Marburg, Germany.
authors.forename: Filippo
authors.initials: F
authors.lastname: Ammazzalorso
authors.affiliation: Hospital of the University of Pennsylvania (UPenn), USA.
authors.forename: Peter H
authors.initials: PH
authors.lastname: Ahn
authors.affiliation: Department of Radiation Oncology, RadboudUMC, Nijmegen, The Netherlands.
authors.forename: Geert O R J
authors.initials: GORJ
authors.lastname: Janssens
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, The Netherlands.
authors.forename: Frank J P
authors.initials: FJP
authors.lastname: Hoebers
authors.affiliation: Department of Radiotherapy and Radiation Oncology, University of Marburg, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Friedmann
authors.affiliation: Hospital of the University of Pennsylvania (UPenn), USA.
authors.forename: Timothy
authors.initials: T
authors.lastname: Solberg
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, The Netherlands.
authors.forename: Sean
authors.initials: S
authors.lastname: Walsh
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, The Netherlands; Department of Radiation Oncology, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany; Institute of Radiooncology, Helmholtz-Zentrum Dresden-Rossendorf, Germany; German Cancer Consortium (DKTK), Dresden and German Cancer Research Center (DKFZ), Heidelberg, Germany.
authors.forename: Esther G C
authors.initials: EGC
authors.lastname: Troost
authors.affiliation: Department of Radiation Oncology, RadboudUMC, Nijmegen, The Netherlands.
authors.forename: Johannes H A M
authors.initials: JHAM
authors.lastname: Kaanders
authors.affiliation: Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, The Netherlands.
authors.forename: Philippe
authors.initials: P
authors.lastname: Lambin
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D003198:Computer Simulation; D005260:Female; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy*; D063193:Heavy Ion Radiotherapy / Q000379:methods; D006801:Humans; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy; D009367:Neoplasm Staging; D016609:Neoplasms, Second Primary / Q000000981:diagnostic imaging / Q000473:pathology / Q000532:radiotherapy; D058958:Organs at Risk / Q000528:radiation effects; D017785:Photons / Q000627:therapeutic use; D061766:Proton Therapy / Q000379:methods*; D011874:Radiometry / Q000379:methods; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods; D000069475:Re-Irradiation / Q000379:methods*; D012189:Retrospective Studies; D000077195:Squamous Cell Carcinoma of Head and Neck; D014057:Tomography, X-Ray Computed
keywords: Head and neck; In silico planning study; Multicentric trial; Particle therapy; Radiotherapy; Re-irradiation