1. Department Head and Neck Oncology, Instituto de Investigación Sanitaria del Principado de Asturias, 33011 Oviedo, Spain
2. Head and Neck Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, 20133 Milan, Italy
3. Department of Translational Research and of New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy
4. UCL Cancer Institute, University College London, London WC1E 6BT, UK
5. Division of Surgery and Interventional Science, Academic Head and Neck Centre University College London, London WC1E 6BT, UK