1. Department of PathologyHaartman InstituteUniversity of HelsinkiHelsinki Finland
2. Department of Oral Medicine and Diagnostic SciencesKing Saud UniversityRiyadh Saudi Arabia
3. Department of Otorhinolaryngology – Head and Neck SurgeryHelsinki University HospitalHelsinki Finland
4. Departments of Surgery and PathologyUniversity of Oulu and Oulu University HospitalOulu Finland
5. Department of Otorhinolaryngology – Head and Neck SurgeryKuopio University Hospital and Institute of Clinical MedicineOtorhinolaryngology – Head and Neck SurgeryUniversity of Eastern FinlandKuopio Finland
6. Department of Oral PathologyInstitute of DentistryUniversity of HelsinkiHelsinki Finland
7. Department of Otorhinolaryngology and Head and Neck SurgeryTampere University HospitalTampere Finland
8. Department of PathologyUniversity of Tampere Central HospitalTampere Finland
9. Department of PathologyUniversity of TurkuTurku Finland
10. Department of Pathology and Forensic MedicineUniversity of Eastern FinlandCancer Center of Eastern FinlandDepartment of PathologyImaging CenterKuopio University HospitalKuopio Finland
11. Department of Otorhinolaryngology – Head and Neck SurgeryOulu University HospitalOulu Finland
12. Department of Otorhinolaryngology – Head and Neck SurgeryTurku University HospitalUniversity of TurkuTurku Finland
13. Department of Diagnostics and Oral MedicineInstitute of DentistryUniversity of Oulu, Oulu, Finland and Oulu University HospitalOulu Finland
14. Institute of DentistryUniversity of HelsinkiHelsinki Finland