title: Targeting hypoxia to overcome radiation resistance in head & neck cancers: real challenge or clinical fairytale?
abstract: BACKGROUND
  Tumor hypoxia is a major cause for failure of therapy in patients with inoperable head and neck cancers.
  
  
  METHODS
  Various anti-hypoxic treatment strategies (e.g. hyperbaric oxygenation, hypoxic cell sensitizers) have been tested in clinical trials in head and neck cancer over the past 30 years and have shown modest improvements in combination with radiotherapy in meta-analyses. Anemia worsens tumor hypoxia, but anemia correction had no significant effect. New approaches (e.g. anti-HIF-directed molecular therapies) have just entered early clinical studies and data are lacking. Expert commentary: A new attractive and promising approach derives from recent advances in imaging and radiotherapy delivery. Progress in imaging of hypoxia (e.g. by positron emission tomography) can select patients for specific therapies and may, in particular, facilitate anti-hypoxia-directed radiotherapy which has become feasible with advanced radiotherapy techniques (IMRT with 'dose-painting'). The combination of both methods may offer a powerful tool for effective targeting of hypoxia in the near future.
authors.affiliation: a Department of Radiation Oncology , Christian-Albrechts-University Kiel , Kiel , Germany.
authors.forename: René
authors.initials: R
authors.lastname: Baumann
authors.affiliation: b Institute of Physiology , University of Luebeck , Luebeck , Germany.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Depping
authors.affiliation: a Department of Radiation Oncology , Christian-Albrechts-University Kiel , Kiel , Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Delaperriere
authors.affiliation: a Department of Radiation Oncology , Christian-Albrechts-University Kiel , Kiel , Germany.
authors.forename: Juergen
authors.initials: J
authors.lastname: Dunst
mesh_terms: D000740:Anemia / Q000150:complications; D000818:Animals; D015687:Cell Hypoxia; D006258:Head and Neck Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D006801:Humans; D006931:Hyperbaric Oxygenation / Q000379:methods; D049268:Positron-Emission Tomography / Q000379:methods; D011836:Radiation Tolerance; D016896:Treatment Outcome
keywords: Head and neck cancers; hypoxia; prognosis; radiotherapy