[1] Univ Udine, ENT Clin, Dept Surg Sci, I-33100 Udine, Italy
[2] Mt Sinai Med Ctr, Dept Otolaryngol Head & Neck Surg, New York, NY 10029 USA
[3] Yeshiva Univ Albert Einstein Coll Med, Montefiore Med Ctr, Dept Surg, Bronx, NY 10461 USA
[4] Univ Cape Town, Fac Hlth Sci, Dept Otolaryngol, ZA-7925 Cape Town, South Africa
[5] Inst Univ Oncol Principado Asturias, Oviedo, Spain
[6] Univ Groningen, Univ Med Ctr Groningen, Dept Radiat Oncol, Groningen, Netherlands
[7] Ctr Oscar Lambret, Dept Cancerol Cervico Faciale, F-59020 Lille, France
[8] Queens Med Ctr, Dept Otolaryngol Head & Neck Surg, Nottingham NG7 2UH, England
[9] Vrije Univ Amsterdam Med Ctr, Dept Otolaryngol Head & Neck Surg, Amsterdam, Netherlands
[10] Emory Univ, Sch Med, Dept Otolaryngol, Atlanta, GA USA
[11] Hull Royal Infirm, Dept Otolaryngol Head & Neck Surg, Kingston Upon Hull HU3 2JZ, N Humberside, England
[12] Univ Michigan, Dept Otolaryngol Head & Neck Surg, Ann Arbor, MI 48109 USA
[13] Hosp Univ Cent Asturias, Dept Otolaryngol, Oviedo, Spain