1. Department of Biomedical Sciences and Medicine; University of Algarve; Faro Portugal
2. Department of Pathology; Brigham and Women's Hospital; Boston MA USA
3. Departments of Pathology and Otolaryngology - Head and Neck Surgery; Johns Hopkins Medical Institutions; Baltimore MD USA
4. Department of Otolaryngology; Hospital Universitario Central de Asturias; Oviedo Spain
5. Department of Otolaryngology - Head and Neck Surgery; Hospital for Sick Children; University of Toronto; Toronto Canada
6. University Hospital of South Manchester NHS Foundation Trust; Manchester UK
7. Division of Pathology; Department of Pediatric Laboratory Medicine; Hospital for Sick Children; University of Toronto; Toronto Canada
8. Division of Hematology/Oncology; Department of Pediatrics; Hospital for Sick Children; Toronto Canada
9. Department of Pathology; The University of Chicago Medicine and Biological Sciences; Chicago IL USA
10. Department of Otolaryngology - Head and Neck Surgery; Auckland City Hospital and Department of Surgery; University of Auckland; Auckland New Zealand
11. Department of Pathology; Portuguese Institute of Oncology; Porto Portugal
12. Anatomic Pathology Department; Braga Hospital; Braga Portugal
13. Anatomic Pathology Department; St Antonio General Hospital; Porto Hospitals Centre; Porto Portugal
14. University of Udine School of Medicine; Udine Italy