1. Department of ENT, Southend University Hospital, Mid and South Essex Foundation Trust, Prittlewell Chase, Westcliff-on-Sea, SS0 0RY, UK
2. Department of ENT, Broomfield Hospital, Mid and South Essex Foundation Trust, Court Road, Broomfield, Chelmsford, CM1 7ET, UK
3. Department of Cellular Pathology, Southend University Hospital, Mid and South Essex Foundation Trust, Prittlewell Chase, Westcliff-on-Sea, SS0 0RY, UK