1. Department of Otorhinolaryngology and Head and Neck Surgery – Academic Alliance Skull Base Pathology Radboudumc & MUMC+ Radboud University Medical Center Nijmegen the Netherlands
2. Rare Cancers, Radboud Institute for Health Sciences Nijmegen the Netherlands
3. Department of Health Evidence Radboud University Medical Center Nijmegen the Netherlands
4. Department of Otolaryngology and Head and Neck Surgery Amsterdam University Medical Centers, VU University Amsterdam the Netherlands
5. Department of Head and Neck Surgery Netherlands Cancer Institute – Antoni van Leeuwenhoek Amsterdam the Netherlands
6. Department of Otorhinolaryngology and Head and Neck Surgery Erasmus Medical Center Rotterdam the Netherlands
7. Department of Otorhinolaryngology and Head and Neck Surgery University of Groningen, University Medical Center Groningen Groningen the Netherlands
8. Department of Otorhinolaryngology and Head and Neck Surgery Haaglanden Medical Center The Hage the Netherlands
9. Department of Otorhinolaryngology and Head and Neck Surgery Leiden University Medical Center Leiden the Netherlands
10. Department of Otorhinolaryngology and Head and Neck Surgery – Academic Alliance Skull Base Pathology Radboudumc & MUMC+ Maastricht University Medical Center Maastricht the Netherlands
11. Department of Head and Neck Surgical Oncology University Medical Center/Utrecht Cancer Center Utrecht the Netherlands
12. Department of Otology & Skull Base Surgery, Eye Ear Nose & Throat Hospital Fudan University Shanghai China
13. Department of Otorhinolaryngology and Skull Base Microsurgery‐Neurosciences Azienda Socio Sanitaria Territoriale Papa Giovanni XXIII Bergamo Italy
14. Department of Otorhinolaryngology and Head and Neck Surgery, The First Faculty of Medicine, Charles University in Prague University Hospital Motol Prague Czech Republic