[1] Guys & St Thomas Hosp NHS Fdn Trust, Dept Otolaryngol, London, England
[2] Royal Devon & Exeter Hosp, Dept Otolaryngol, Exeter, Devon, England
[3] Univ Padua, Dept Mol Med, Padua, Italy
[4] Yale Univ, Sch Med, Liver Ctr, New Haven, CT USA
[5] Yale Univ, Sch Med, Dept Internal Med, Sect Digest Dis, New Haven, CT 06510 USA
[6] Univ Padua, Dept Neurosci, Sect Otolaryngol, Treviso, Italy
[7] Univ Cambridge, Med Lib, Cambridge, England
[8] Ctr Riferimento Oncol Aviano CRO IRCCS, Unit Canc Epidemiol, Aviano, Italy