1. Department of Otolaryngology; Harvard Medical School; Boston Massachusetts
2. Department of Otorhinolaryngology; Tampere University Hospital and the University of Tampere; Tampere Finland
3. Department of Otolaryngology, Chang-Gung Memorial Hospital; Chang-Gung University; Taoyuan Taiwan
4. Department of Pathology, Massachusetts General Hospital; Harvard Medical School; Boston Massachusetts
5. Department of Pathology , Boston Children's Hospital; Harvard Medical School; Boston Massachusetts
6. Department of Otorhinolaryngology; Oslo University Hospital; Rikshospitalet Oslo Norway