1 Department of Clinical Oncology, Freeman Hospital, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne NE7 7DN, United Kingdom. Electronic address: anthony.waton1@nhs.net.
2 Department of Pathology, Freeman Hospital, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne NE7 7DN, United Kingdom. Electronic address: anne.chambers@nhs.net.
3 Department of Head and Neck Surgery, Freeman Hospital, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne NE7 7DN, United Kingdom. Electronic address: hannah.fox14@nhs.net.
4 Department of Head and Neck Surgery, Freeman Hospital, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne NE7 7DN, United Kingdom. Electronic address: j.ohara@nhs.net.
5 Department of Clinical Oncology, Freeman Hospital, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne NE7 7DN, United Kingdom. Electronic address: shahid.iqbal@nhs.net.