1 UCL Cancer Institute, University College London, London, UK. Electronic address: oliver.jones8@nhs.net.
2 Research Department of Infection & Population Health, University College London, London, UK.
3 Cardiff University, UK; ENT Department, Royal London Hospital, Barts Health NHS Trust and Head and Neck Centre, University College London Hospitals NHS Trust, London, UK.
4 UCL Cancer Institute, University College London, London, UK; ENT Department, Royal London Hospital, Barts Health NHS Trust and Head and Neck Centre, University College London Hospitals NHS Trust, London, UK.