title: Increase in Tumor Control and Normal Tissue Complication Probabilities in Advanced Head-and-Neck Cancer for Dose-Escalated Intensity-Modulated Photon and Proton Therapy.
abstract: BACKGROUND
  Presently used radiochemotherapy regimens result in moderate local control rates for patients with advanced head-and-neck squamous cell carcinoma (HNSCC). Dose escalation (DE) may be an option to improve patient outcome, but may also increase the risk of toxicities in healthy tissue. The presented treatment planning study evaluated the feasibility of two DE levels for advanced HNSCC patients, planned with either intensity-modulated photon therapy (IMXT) or proton therapy (IMPT).
  
  
  METHODS
  For 45 HNSCC patients, IMXT and IMPT treatment plans were created including DE via a simultaneous integrated boost (SIB) in the high-risk volume, while maintaining standard fractionation with 2 Gy per fraction in the remaining target volume. Two DE levels for the SIB were compared: 2.3 and 2.6 Gy. Treatment plan evaluation included assessment of tumor control probabilities (TCP) and normal tissue complication probabilities (NTCP).
  
  
  RESULTS
  An increase of approximately 10% in TCP was estimated between the DE levels. A pronounced high-dose rim surrounding the SIB volume was identified in IMXT treatment. Compared to IMPT, this extra dose slightly increased the TCP values and to a larger extent the NTCP values. For both modalities, the higher DE level led only to a small increase in NTCP values (mean differences <2%) in all models, except for the risk of aspiration, which increased on average by 8 and 6% with IMXT and IMPT, respectively, but showed a considerable patient dependence.
  
  
  CONCLUSIONS
  Both DE levels appear applicable to patients with IMXT and IMPT since all calculated NTCP values, except for one, increased only little for the higher DE level. The estimated TCP increase is of relevant magnitude. The higher DE schedule needs to be investigated carefully in the setting of a prospective clinical trial, especially regarding toxicities caused by high local doses that lack a sound dose-response description, e.g., ulcers.
authors.affiliation: OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf , Dresden , Germany.
authors.forename: Annika
authors.initials: A
authors.lastname: Jakobi
authors.affiliation: OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf , Dresden , Germany ; German Cancer Consortium (DKTK), Partner Site Dresden , Dresden , Germany ; German Cancer Research Center (DKFZ) , Heidelberg , Germany.
authors.forename: Armin
authors.initials: A
authors.lastname: Lühr
authors.affiliation: OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf , Dresden , Germany.
authors.forename: Kristin
authors.initials: K
authors.lastname: Stützer
authors.affiliation: OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf , Dresden , Germany ; Department of Radiation Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden , Dresden , Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Bandurska-Luque
authors.affiliation: OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf , Dresden , Germany.
authors.forename: Steffen
authors.initials: S
authors.lastname: Löck
authors.affiliation: OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf , Dresden , Germany ; German Cancer Consortium (DKTK), Partner Site Dresden , Dresden , Germany ; German Cancer Research Center (DKFZ) , Heidelberg , Germany ; Department of Radiation Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden , Dresden , Germany ; Institute of Radiooncology, Helmholtz-Zentrum Dresden - Rossendorf , Dresden , Germany.
authors.forename: Mechthild
authors.initials: M
authors.lastname: Krause
authors.affiliation: OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf , Dresden , Germany ; German Cancer Consortium (DKTK), Partner Site Dresden , Dresden , Germany ; German Cancer Research Center (DKFZ) , Heidelberg , Germany ; Department of Radiation Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden , Dresden , Germany ; Institute of Radiooncology, Helmholtz-Zentrum Dresden - Rossendorf , Dresden , Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Baumann
authors.affiliation: OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf , Dresden , Germany.
authors.forename: Rosalind
authors.initials: R
authors.lastname: Perrin
authors.affiliation: OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf , Dresden , Germany ; German Cancer Consortium (DKTK), Partner Site Dresden , Dresden , Germany ; German Cancer Research Center (DKFZ) , Heidelberg , Germany ; Department of Radiation Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden , Dresden , Germany ; Institute of Radiooncology, Helmholtz-Zentrum Dresden - Rossendorf , Dresden , Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Richter
keywords: head-and-neck cancer; normal tissue complication probability; photon radiotherapy; proton radiotherapy; tumor control probability