[1] Univ Oviedo, Hosp Univ Cent Asturias, Dept Otolaryngol, CIBERONC,ISPA,IUOPA, Oviedo, Spain
[2] Univ Oklahoma, Hlth Sci Ctr, Dept Otorhinolaryngol, Oklahoma City, OK USA
[3] Univ Arizona, Coll Med Phoenix, Dept Surg, Phoenix, AZ USA
[4] Southern Illinois Univ, Sch Med, Dept Otolaryngol Head & Neck Surg, Springfield, IL USA
[5] UC Louvain, St Luc Univ Hosp, Dept Otorhinolaryngol Head & Neck Surg, B-1200 Brussels, Belgium
[6] King Albert II Canc Inst, Inst Rech Expt, B-1200 Brussels, Belgium
[7] Univ Helsinki, Fac Med, Dept Otorhinolaryngol Head & Neck Surg, Res Program Syst Oncol, Helsinki, Finland
[8] Helsinki Univ Hosp, Helsinki, Finland
[9] Univ Med Ctr Utrecht, Dept Head & Neck Surg Oncol, Utrecht, Netherlands
[10] Radboud Univ Nijmegen, Med Ctr, Dept Otolaryngol Head & Neck Surg, Nijmegen, Netherlands
[11] Univ Zielona Gora, Dept Otolaryngol & Maxillofacial Surg, Zielona Gora, Poland
[12] Poznan Univ Med Sci, Dept Maxillofacial Surg, Poznan, Poland
[13] Univ Sao Paulo, Head & Neck Surg Dept, Med Sch, Sao Paulo, Brazil
[14] AC Camargo Canc Ctr, Head & Neck Surg & Otorhinolaryngol Dept, Sao Paulo, Brazil
[15] Johns Hopkins Univ, Dept Oncol, Baltimore, MD USA
[16] Hokkaido Univ, Fac Med, Dept Otolaryngol Head & Neck Surg, Sapporo, Japan
[17] Hokkaido Univ, Grad Sch Med, Sapporo, Japan
[18] Univ Texas MD Anderson Canc Ctr, Dept Head & Neck Surg, Div Surg, Houston, TX USA
[19] Policlin Citta Udine, ENT Unit, Udine, Italy
[20] Int Head & Neck Sci Grp, Padua, Italy
[21] Univ Oviedo, Hosp Univ Cent Asturias, Dept Otolaryngol, Ave Roma SN, Oviedo 33011, Asturias, Spain