UCL Cancer Institute, University College London, London, UK; Academic Head and Neck Centre, UCL Division of Surgery and Interventional Science, University College London, London, UK; ENT Department, Barts Health NHS Trust, London, United Kingdom; Rhinology & Endoscopic Skull Base Surgery, Department of Otolaryngology-H&N Surgery, Stanford University School of Medicine, Palo Alto, USA. Electronic address: m.lechner@ucl.ac.uk.